Document:

<PAGE>

                                                                  EXHIBIT 10.11

                                                                  EXECUTION COPY

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                         MASTER RESTRUCTURING AGREEMENT

                                  BY AND AMONG

                         METROMEDIA FIBER NETWORK, INC.,

                     METROMEDIA FIBER NETWORK SERVICES, INC.

                                       AND

                               BECHTEL CORPORATION

                         -------------------------------

                           DATED AS OF OCTOBER 1, 2001
                         -------------------------------

--------------------------------------------------------------------------------

<PAGE>

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                               PAGE
<S>      <C>                                                                                   <C>

                                    ARTICLE I

                                   DEFINITIONS

1.1      DEFINITIONS...........................................................................  2
         -----------

                                   ARTICLE II

                              BECHTEL RESTRUCTURING

2.1      RESTRUCTURING......................................................................... 11
         -------------
2.2      CLOSING............................................................................... 11
         -------

                                   ARTICLE III

             REPRESENTATIONS AND WARRANTIES OF THE COMPANY AND MFNS

3.1      CORPORATE EXISTENCE AND POWER........................................................ 12
         -----------------------------
3.2      AUTHORIZATION........................................................................ 12
         -------------
3.3      GOVERNMENTAL AUTHORIZATION; THIRD PARTY CONSENTS..................................... 13
         ------------------------------------------------
3.4      COMPLIANCE WITH LAWS; PERMITS........................................................ 13
         -----------------------------
3.5      LICENSES............................................................................. 14
         --------
3.6      PRIVATE LICENSES..................................................................... 14
         ----------------
3.7      FRANCHISES........................................................................... 15
         ----------
3.8      COMPLIANCE WITH OTHER INSTRUMENTS.................................................... 15
         ---------------------------------
3.9      NO MATERIAL MISSTATEMENTS............................................................ 15
         -------------------------
3.10     PERFECTION AND PRIORITY OF LIENS..................................................... 16
         --------------------------------
3.11     VALID ISSUANCE OF COMMON STOCK....................................................... 16
         ------------------------------
3.12     CAPITALIZATION AND VOTING RIGHTS..................................................... 17
         --------------------------------
3.13     SUBSIDIARIES......................................................................... 18
         ------------
3.14     AGREEMENTS........................................................................... 18
         ----------
3.15     LITIGATION........................................................................... 19
         ----------
3.16     TITLE TO PROPERTY, ASSETS AND LEASES................................................. 19
         ------------------------------------
3.17     ENVIRONMENTAL MATTERS................................................................ 20
         ---------------------
3.18     TAX RETURNS.......................................................................... 20
         -----------
3.19     PENSION PLANS........................................................................ 20
         -------------
3.20     INVESTMENT COMPANY ACT............................................................... 21
         ----------------------
3.21     PUBLIC UTILITY HOLDING COMPANY ACT................................................... 21
         ----------------------------------
3.22     FEDERAL RESERVE REGULATIONS.......................................................... 21
         ---------------------------
3.23     NO DEFAULT........................................................................... 21
         ----------
3.24     INSURANCE............................................................................ 21
         ---------
3.25     SOLVENCY............................................................................. 21
         --------
</TABLE>

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<TABLE>
<S>      <C>                                                                                   <C>

3.26     PROJECTED FINANCIAL STATEMENTS......................................................... 21
         ------------------------------
3.27     NO MATERIAL ADVERSE CHANGE............................................................. 22
         --------------------------
3.28     SEC DOCUMENTS; FINANCIAL STATEMENTS.................................................... 22
         -----------------------------------
3.29     PRIVATE OFFERING....................................................................... 22
         ----------------
3.30     TERMS OF CERTAIN OTHER DEBT AGREEMENTS................................................. 23
         --------------------------------------
3.31     AMOUNTS OWED UNDER THE MASTER SERVICES AGREEMENT....................................... 23
         ------------------------------------------------
3.32     PURCHASE MONEY INDEBTEDNESS............................................................ 23
         ---------------------------
3.33     OTHER RESTRUCTURING AGREEMENTS......................................................... 23
         ------------------------------
3.34     RESTRICTIONS ON COLLATERAL............................................................. 23
         --------------------------
3.35     WRITTEN CONSENT........................................................................ 24
         ---------------
3.36     BROKERS................................................................................ 24
         -------

                                   ARTICLE IV

                    REPRESENTATIONS AND WARRANTIES OF BECHTEL

4.1      PURCHASE FOR OWN ACCOUNT............................................................... 24
         ------------------------
4.2      RESTRICTED SECURITIES.................................................................. 25
         ---------------------
4.3      ACCREDITED INVESTOR.................................................................... 25
         -------------------
4.4      EXISTENCE AND POWER.................................................................... 25
         -------------------
4.5      AUTHORIZATION; NO CONTRAVENTION........................................................ 25
         -------------------------------
4.6      BINDING EFFECT......................................................................... 25
         --------------
4.7      DISCLOSURE OF INFORMATION.............................................................. 26
         -------------------------

                                    ARTICLE V

                          CONDITIONS TO THE OBLIGATION
                               OF BECHTEL TO CLOSE

5.1      REPRESENTATION AND WARRANTIES.......................................................... 26
         -----------------------------
5.2      COMPLIANCE WITH THIS AGREEMENT......................................................... 26
         ------------------------------
5.3      WARRANT AGREEMENT, NOTE AND OTHER DOCUMENTATION........................................ 26
         -----------------------------------------------
5.4      ORGANIZATIONAL DOCUMENTS, ETC.......................................................... 27
         -----------------------------
5.5      FINANCIAL OFFICER'S CERTIFICATES....................................................... 27
         --------------------------------
5.6      CONSENTS............................................................................... 27
         --------
5.7      OPINIONS OF COUNSEL TO THE OBLIGORS.................................................... 27
         -----------------------------------
5.8      FEES................................................................................... 28
         ----
5.9      ISSUANCE OF CONVERTIBLE DEBT OR EQUITY................................................. 28
         --------------------------------------
5.10     VERIZON DEBT AGREEMENT................................................................. 28
         ----------------------
5.11     VENDOR AGREEMENTS...................................................................... 28
         -----------------
5.12     CITICORP FACILITY...................................................................... 29
         -----------------
5.13     OTHER TRANSACTIONS..................................................................... 29
         ------------------
5.14     FINANCIAL PROJECTIONS.................................................................. 29
         ---------------------
5.15     NO MATERIAL ADVERSE CHANGE............................................................. 29
         --------------------------
5.16     NO MATERIAL JUDGMENT OR ORDER.......................................................... 29
         -----------------------------
5.17     NO LITIGATION.......................................................................... 30
         -------------
5.18     INSURANCE.............................................................................. 30
         ---------
</TABLE>

                                      (ii)
<PAGE>

<TABLE>
<S>      <C>                                                                                   <C>

5.19     DUE DILIGENCE.......................................................................... 30
         -------------
5.20     BASIC DOCUMENTS........................................................................ 30
         ---------------
5.21     MECHANICS' AND MATERIALMANS' LIENS..................................................... 30
         ----------------------------------
5.22     CERTAIN ADDITIONAL CONDITIONS.......................................................... 30
         -----------------------------
5.23     OTHER.................................................................................. 31
         -----

                                   ARTICLE VI

                                OTHER AGREEMENTS

6.1      MODIFICATION OF OTHER RESTRUCTURING AGREEMENTS......................................... 31
         ----------------------------------------------
6.2      TERMINATION AND RELEASE................................................................ 31
         -----------------------
6.3      LIQUIDATED DAMAGES AMOUNT.............................................................. 32
         -------------------------
6.4      WRITTEN CONSENT........................................................................ 33
         ---------------

                                   ARTICLE VII

                                 INDEMNIFICATION

7.1      INDEMNIFICATION........................................................................ 34
         ---------------
7.2      CONTRIBUTION........................................................................... 34
         ------------

                                  ARTICLE VIII

                            TERMINATION OF AGREEMENT

8.1      TERMINATION............................................................................ 35
         -----------
8.2      SURVIVAL............................................................................... 36
         --------

                                   ARTICLE IX

                                  MISCELLANEOUS

9.1      SURVIVAL OF REPRESENTATIONS AND WARRANTIES............................................. 36
         ------------------------------------------
9.2      NOTICES................................................................................ 36
         -------
9.3      SUCCESSORS AND ASSIGNS; THIRD PARTY BENEFICIARIES...................................... 37
         -------------------------------------------------
9.4      AMENDMENT AND WAIVER................................................................... 37
         --------------------
9.5      COUNTERPARTS........................................................................... 38
         ------------
9.6      HEADINGS............................................................................... 38
         --------
9.7      GOVERNING LAW.......................................................................... 38
         -------------
9.8      SEVERABILITY........................................................................... 38
         ------------
9.9      RULES OF CONSTRUCTION.................................................................. 38
         ---------------------
9.10     ENTIRE AGREEMENT....................................................................... 39
         ----------------
9.11     FURTHER ASSURANCES..................................................................... 39
         ------------------
9.12     PUBLICITY.............................................................................. 39
         ---------
</TABLE>

                                     (iii)
<PAGE>

EXHIBITS

A             Form of Note
B             Form of Warrant Agreement
C             Form of Intercreditor and Collateral Agency Agreement
D             Form of Registration Rights Agreement
E             Form of Junior Security Agreement
F 1           Form of Paul, Weiss, Rifkind, Wharton, & Garrison Opinion
F-2           Form of Akin, Gump, Strauss, Hauer, & Feld, L.L.P. Opinion
G             Form of Written Consent

SCHEDULES

1.1           Convertible Securities Issued in Connection with the Restructuring
3.12          Convertible Securities and Options; Other Registrable Securities
3.15          Legal Proceedings
5.11          Vendor Agreements

                                      (iv)
<PAGE>

                         MASTER RESTRUCTURING AGREEMENT

                  MASTER RESTRUCTURING AGREEMENT, dated as of October 1, 2001
(this "AGREEMENT"), by and between METROMEDIA FIBER NETWORK, INC., a Delaware
corporation (the "COMPANY"), METROMEDIA FIBER NETWORK SERVICES, INC., a Delaware
corporation and wholly-owned Subsidiary of the Company ("MFNS"), and BECHTEL
CORPORATION, a Nevada corporation ("BECHTEL").

                  WHEREAS, the Company and MFNS have each negotiated with
certain of their respective existing creditors and vendors as well as certain
new lenders, to provide additional liquidity to the Company and its Subsidiaries
by restructuring certain payables owed by the Company and/or its Subsidiaries to
such existing creditors and vendors (including the Nortel Financing and the
Vendor Financings) and/or the extension by such new lenders of additional debt
financing to the Company (including the Citicorp Facility, the Affiliate
Financing and the Verizon Facility) (the "RESTRUCTURING").

                  WHEREAS, in order to facilitate the Restructuring, the
Company, MFNS and Bechtel have agreed to restructure certain amounts owed by the
Company and MFNS to Bechtel pursuant to the Master Services Agreement and the
ancillary agreements thereto (the "BECHTEL RESTRUCTURING").

                  WHEREAS, the Company, MFNS and Bechtel have agreed that as
final settlement for and in order for the Company and its Subsidiaries to
finance the engineering, construction, installation, acquisition, lease,
development and/or improvement of a portion of MFNS' fiber optic network and
other Telecommunications Assets and all amounts due and owing to Bechtel under
the Master Services Agreement in respect thereof (except as set forth in
SECTIONS 6.2 and 6.3 hereof), and in order to effectuate the Bechtel
Restructuring, the Company will (i) pay to Bechtel the sum of US$9 million, (ii)
cause MFNS to issue to Bechtel an 8.5% convertible secured promissory note
substantially in the form of EXHIBIT A attached hereto (the "NOTE"), which Note
shall, among other things, be (a) convertible into shares of the Company's class
A common stock, par value US$0.01 per share ("COMMON STOCK"), (b) secured by the
assets set forth opposite Bechtel's name on ANNEX 2 to the Intercreditor and
Collateral Agency Agreement and (c) in the aggregate principal amount of US$89
million, (iii) issue to Bechtel a warrant (the "WARRANT") pursuant to the terms
of the Warrant Agreement substantially in the form of EXHIBIT B attached hereto
(the "WARRANT AGREEMENT"), which Warrant shall be exercisable for 25,000,000
shares of Common Stock in accordance with the terms thereof and (iv) terminate
the Master Services Agreement (except as set forth in SECTIONS 6.2 and 6.3
hereof), in each case in accordance with and pursuant to the terms of this
Agreement.

                  NOW, THEREFORE, in consideration of the mutual covenants and
agreements set forth herein, as final settlement of all amounts due and owing to
Bechtel, MFN and its Subsidiaries under the Master Services Agreement (except as
set forth in

<PAGE>

SECTION 6.2 and 6.3 hereof), and for other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, the parties hereto agree
as follows:

                                   ARTICLE I

                                  DEFINITIONS

                  1.1  DEFINITIONS.  As used in this Agreement, and unless the
context requires a different meaning, the following terms have the meanings
indicated:

                  "ADMINISTRATIVE AGENT" has the meaning set forth in the
Citicorp Facility.

                  "AFFILIATE" means any Person who is an "affiliate" as defined
in Rule 12b-2 of the General Rules and Regulations under the Exchange Act.

                  "AFFILIATE FINANCING" has the meaning in the definition of
8.5% Senior Convertible Notes.

                  "AGREEMENT" means this Agreement as the same may be amended,
supplemented or modified in accordance with the terms hereof.

                  "BASIC DOCUMENTS" has the meaning set forth in the Citibank
Facility.

                  "BECHTEL" has the meaning set forth in the preamble to this
Agreement.

                  "BECHTEL PARTIES" has the meaning set forth in SECTION 7.6 of
this Agreement.

                  "BECHTEL RESTRUCTURING" has the meaning set forth in the
recitals to this Agreement.

                  "BOARD OF DIRECTORS" means the board of directors of the
Company.

                  "BUSINESS DAY" means any day other than a Saturday, Sunday or
other day on which commercial banks in the State of New York are authorized or
required by law or executive order to close.

                  "BY-LAWS" means the by-laws of the Company in effect on the
Closing Date, as the same may be amended from time to time.

                  "CAPITAL STOCK" means (i) in the case of a corporation,
corporate stock, (ii) in the case of an association or business entity, any and
all shares, interests, participations, rights or other equivalents (however
designated) of corporate stock, (iii) in the case of a partnership or limited
liability company, partnership or membership interests (whether general or
limited) and (iv) any other interest or participation that confers on a Person
the right to receive a share of the profits and losses of, or distributions of
assets of, the issuing person.

                                       2
<PAGE>

                  "CASH PAYMENT" has the meaning set forth in SECTION 2.1(a) of
this Agreement.

                  "CERTIFICATE OF INCORPORATION" means the Certificate of
Incorporation of the Company in effect on the Closing Date, as the same may be
amended from time to time.

                  "CITICORP FACILITY" means, collectively, the US$150 million
Note and Guarantee Agreement, dated as of September 6, 2001, by and among the
Company, the other Obligors party thereto, the Purchasers party thereto and
Citicorp USA, Inc., as administrative agent, as amended by that certain
Amendment No. 1, dated as of September 17, 2001 and that certain Amendment No.
2, dated as of October 1, 2001.

                  "CLAIMS" has the meaning set forth in SECTION 6.2(c) of this
Agreement.

                  "CLASS B COMMON STOCK" means shares of the Company's class B
common stock, US$0.01 par value per share.

                  "CLOSING" has the meaning set forth in SECTION 2.2 of this
Agreement.

                  "CLOSING DATE" has the meaning set forth in SECTION 2.2 of
this Agreement.

                  "CODE" means the Internal Revenue Code of 1986, as amended, or
any successor statute thereto.

                  "COLLATERAL AGENT" means First Union National Bank.

                  "COMMISSION" means the United States Securities and Exchange
Commission.

                  "COMMON STOCK" has the meaning set forth in the recitals to
this Agreement.

                  "COMPANY" has the meaning set forth in the preamble to this
Agreement.

                  "COMPANY PARTIES" has the meaning in SECTION 6.2 of this
Agreement.

                  "COMPANY STOCKHOLDERS' MEETING" has the meaning set forth in
SECTION 6.4(a) of this Agreement.

                  "CONDITION OF THE COMPANY" means, individually or in the
aggregate, the assets, business, properties, liabilities, operations or
condition (financial or otherwise) or material agreements of the Company and
each of its Subsidiaries.

                  "CONVERTIBLE SECURITIES" has the meaning set forth in the
Warrant Agreement.

                  "DEFAULT" has the meaning set forth in the Note.

                                       3
<PAGE>

                  "DEPOSITARY AGREEMENT" means that certain Depositary Agreement
among the Company, Wilmington Trust Company, as Trustee acting on behalf of the
Holders of the Notes, Verizon Investments Inc., and Wilmington Trust Company, as
Depositary Agent, dated as of October 1, 2001, executed in connection with the
Verizon Financing.

                  "8.5% SENIOR CONVERTIBLE NOTES" means those certain 8.5%
Senior Convertible Notes issued to John W. Kluge, Chase Manhattan Bank and
Stuart Subotnick, trustees under a Trust Agreement between John W. Kluge, as
grantor and John W. Kluge and Manufacturers Hanover Trust Company, as Trustees,
dated May 30, 1984, as amended and restated, David Rockefeller and Stephen A.
Garofalo (or their respective Affiliates) as part of the affiliate financing in
the aggregate principal amount of not less than US$180 million (the "AFFILIATE
FINANCING").

                  "ENVIRONMENTAL CLAIM" means any liability, contingent or
otherwise (including any liability for damages, costs of environmental
remediation, fines, penalties or indemnities, and including any Lien filed
against any property covered by any Junior Security Document in favor of any
Governmental Authority), of the Company, MFNS or any Restricted Subsidiary
directly or indirectly resulting from or based upon (a) a violation of any
Environmental Law, (b) the generation, use, handling, transportation, storage,
treatment or disposal of any Hazardous Materials, (c) exposure to any Hazardous
Materials, (d) the release or threatened release of any Hazardous Materials into
the environment or (e) any contract, agreement or other consensual arrangement
pursuant to which liability is assumed or imposed with respect to any of the
foregoing.

                  "ENVIRONMENTAL LAWS" means all laws, rules, regulations,
codes, ordinances, orders, decrees, judgments, injunctions, notices or binding
agreements issued, promulgated or entered into by any Governmental Authority,
relating in any way to the environment, preservation or reclamation of natural
resources, the management, release or threatened release of any Hazardous
Material or to health and safety matters.

                  "ENVIRONMENTAL PERMIT" means any permit, approval,
authorization, certificate, registration, license, variance, filing, permission
or other approval required by or from any Government Authority pursuant to any
Environmental Law.

                  "ERISA" means the Employee Retirement Income Security Act of
1974, as the same may be amended from time to time.

                  "ERISA AFFILIATE" means any trade or business (whether or not
incorporated) that, together with the Company, is treated as a single employer
under Section 414(b) or (c) of the Code or, solely for purposes of Section 302
of ERISA and Section 412 of the Code, is treated as a single employer under
Section 414 of the Code.

                  "ERISA EVENT" means (a) any "reportable event", as defined in
Section 4043 of ERISA or the regulations issued thereunder, with respect to a
Plan with respect to which notice is required to be given to the PBGC; (b) the
adoption of any amendment to a Plan that would require the provision of security
pursuant to Section 401(a)(29) of the Code or Section 307 of ERISA; (c) the
existence with respect to

                                       4
<PAGE>

any Plan of an "accumulated funding deficiency" (as defined in Section 412 of
the Code or Section 302 of ERISA), whether or not waived; (d) the filing
pursuant to Section 412(d) of the Code or Section 303 of ERISA of an application
for a waiver of the minimum funding standard with respect to any Plan; (e) the
incurrence of any liability under Title IV of ERISA with respect to the
termination of any Plan or the withdrawal or partial withdrawal of the Company
or any of its ERISA Affiliates from any Plan or Multiemployer Plan; (f) the
receipt by the Company or any ERISA Affiliate from the PBGC or a plan
administrator of any notice relating to the intention to terminate any Plan or
Plans or, in the case of the PBGC, to appoint a trustee to administer any Plan;
(g) the receipt by the Company or any ERISA Affiliate of any notice concerning
the imposition of Withdrawal Liability or a determination that a Multiemployer
Plan is, or is expected to be, insolvent or in reorganization, within the
meaning of Title IV of ERISA; (h) the occurrence of a "prohibited transaction"
with respect to which the Company or any of its Subsidiaries is a "disqualified
person" (within the meaning of Section 4975 of the Code) or with respect to
which the Company or any Restricted Subsidiary could otherwise be liable; and
(i) any other event or condition with respect to a Plan or Multiemployer Plan
that could reasonably be expected to result in liability of the Company or any
of its Subsidiaries.

                  "EVENT OF DEFAULT" has the meaning set forth in the Note.

                  "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations of the Commission thereunder.

                  "FINANCIAL STATEMENTS" has the meaning set forth in SECTION
3.28 of this Agreement.

                  "FRANCHISE" means a franchise, license, authorization or right
by contract or otherwise to construct, own, operate, promote and/or extend any
Telecommunications Asset operated or to be operated by the Company or any of its
Restricted Subsidiaries granted by any state, county, city, town, village or
other local or state government authority. The term "Franchise" shall include
each of the Franchises set forth on SCHEDULE 4.01(u) of the Citicorp Facility.

                  "GAAP" has the meaning set forth in the Warrant Agreement.

                  "GOVERNMENTAL AUTHORITY" means any national, federal, state,
provincial, territorial, municipal, regional, local or foreign judicial,
administrative or governmental agency, board, authority, instrumentality or
other law, regulatory or rule-making body.

                  "HAZARDOUS MATERIALS" means all explosive or radioactive
substances or wastes and all hazardous or toxic substances, wastes or other
pollutants, including petroleum or petroleum distillates, asbestos or asbestos
containing materials, polychlorinated biphenyls, radon gas, infectious or
medical wastes and all other substances or wastes of any nature regulated
pursuant to any Environmental Law.

                  "INDEBTEDNESS" has the meaning set forth in the Citicorp
Facility.

                                       5
<PAGE>

                  "INDEMNIFIED PERSON" has the meaning set forth in SECTION 7.1
of this Agreement.

                  "INDENTURES" means (i) the Indenture, dated as of November 25,
1998, by and between the Company and The Bank of New York, as successor to IBJ
Schroeder Bank & Trust Company, as trustee, as amended by the First Supplemental
Indenture dated September 26, 2001 and (ii) the Indenture, dated as of November
17, 1999, by and between the Company and The Bank of New York, as trustee, as
amended by the First Supplemental Indenture dated September 26, 2001.

                  "INFORMATION STATEMENT" has the meaning given to such term in
SECTION 6.4(a) hereof.

                  "INTERCREDITOR AND COLLATERAL AGENCY AGREEMENT" means the
Junior Intercreditor and Collateral Agency Agreement substantially in the form
of EXHIBIT C attached hereto.

                  "JUNIOR SECURITY AGREEMENT" means the Junior Security
Agreement substantially in the form of EXHIBIT E attached hereto.

                  "JUNIOR SECURITY DOCUMENTS" has the meaning set forth in the
Citicorp Facility.

                  "LETTER AGREEMENT" means that certain letter agreement, dated
October 1, 2001 from MFN and MFNS to Bechtel.

                  "LICENSES" means all licenses, writs, permits, approvals,
authorizations, consents, orders, certificates, waivers, franchises and
registrations now existing or hereafter granted to or in favor of the Company or
any Restricted Subsidiary by any Government Authority including the licenses
described in SCHEDULE 4.01(t) of the Citicorp Facility.

                  "LIEN" means any mortgage, deed of trust, pledge,
hypothecation, assignment, encumbrance, lien (statutory or other) or preference,
priority, right or other security interest or preferential arrangement of any
kind or nature whatsoever (excluding preferred stock and equity related
preferences).

                  "MARGIN STOCK" has the meaning set forth in the Citicorp
Facility.

                  "MASTER SERVICES AGREEMENT" means that certain Master Services
Agreement, dated as of May 3, 2000, by and between Bechtel and the Company.

                  "MATERIAL ADVERSE EFFECT" means (a) a materially adverse
effect on the Condition of the Company, (b) a material impairment of the ability
of either the Company or its Subsidiaries, taken as a whole, to perform their
respective obligations under the Transaction Documents, the Indentures or any
Basic Document or (c) a material impairment of the rights of or benefits
available to Bechtel under the Transaction

                                       6
<PAGE>

Documents or to the Collateral Agent in connection with the Intercreditor and
Collateral Agency Agreement and the security granted in connection therewith.

                  "MATERIAL AGREEMENT" means, collectively, (a) the Senior Notes
and the Subordinated Notes (and any indenture relating thereto), (b) the Nortel
Agreement and the other Vendor Agreements, (c) the Verizon Agreement and Verizon
Debt Agreement, (d) any agreement with a vendor or contractor pursuant to which
the Company reasonably anticipates that the Company and its Subsidiaries will
purchase in the aggregate more than US$50,000,000 of equipment or construction
services, (e) any agreement providing for the sale or lease of fiber by the
Company or any Restricted Subsidiary for aggregate consideration of
US$50,000,000 or more, (f) the Citicorp Facility, (g) all agreements entered
into in connection with the Affliate Financing and (h) the other agreements
listed in SCHEDULE 4.01(k) of the Citicorp Facility.

                  "MFNS" has the meaning set forth in the preamble to this
Agreement.

                  "MULTIEMPLOYER PLAN" means a multiemployer plan as defined in
Section 4001(a)(3) of ERISA.

                  "NASDAQ" has the meaning set forth in SECTION 6.4(a) of this
Agreement.

                  "NOTE" has the meaning set forth in the recitals to this
Agreement.

                  "NORTEL" has the meaning set forth in SECTION 5.11 of this
Agreement.

                  "NORTEL AGREEMENT" has the meaning set forth in the Citicorp
Facility.

                  "NORTEL FINANCING" means a financing arrangement of not less
than US$231 million between Nortel, as lender, on the one hand, and the Company
or MFNS, as borrower, on the other hand, as more particularly described in
SECTION 5.11 to this Agreement.

                  "OBLIGORS" has the meaning set forth in the Citicorp Facility.

                  "OPTIONS" has the meaning set forth in the Warrant Agreement.

                  "ORDERS" means judgments, injunctions, writs, awards, decree
or an order of any nature.

                  "OTHER WARRANTS" means those certain warrants issued to (i)
purchasers under the Citicorp Facility pursuant to the Warrant Agreement
attached as Exhibit H thereto, (ii) Nortel in respect of the Nortel Financing
and (iii) to certain Vendors in respect of the Vendor Financings. SCHEDULE 1
hereto contains a list of all Convertible Securities issued in respect of the
Restructuring, including the number of shares of Common Stock to be issued and
upon conversion, exchange or exercise thereof and the conversion or exchange
rate or exercise price in respect thereof.

                  "PBGC" means the Pension Benefit Guaranty Corporation.

                                       7
<PAGE>

                  "PERSON" means any individual, firm, corporation, partnership,
trust, incorporated or unincorporated association, joint venture, joint stock
company, limited liability company, limited liability partnership, Governmental
Authority or other entity of any kind, and shall include any successor (by
merger or otherwise) of such entity.

                  "PLAN" means any employee pension benefit plan (other than a
Multiemployer Plan) subject to the provisions of Title IV of ERISA or Section
412 of the Code or Section 307 of ERISA, and in respect of which the Company or
any ERISA Affiliate is (or, if such plan were terminated, would under Section
4069 of ERISA be deemed to be) an "employer" as defined in Section 3(5) of
ERISA.

                  "PRIVATE LICENSES" means an license, agreement, lease,
authorization or right by contract entered into with, or granted by, a
non-governmental Person in connection with the construction, ownership or
operation by the Company or any of its Subsidiaries of Telecommunications
Assets, including, but not limited to easements, right-of-way agreements, tunnel
duct lease agreements, indefeasible right of use agreements, transmission
attachment licenses, underground license agreements and pole, conduit and/or
trench license agreements.

                  "PROXY STATEMENT" has the meaning set forth in SECTION 6.4(a)
of this Agreement.

                  "REGISTRATION RIGHTS AGREEMENT" means the Registration Rights
Agreement substantially in the form of EXHIBIT D attached hereto.

                  "REGULATION T", "REGULATION U" and "REGULATION X" have the
meaning set forth in the Citicorp Facility.

                  "REQUIREMENTS OF LAW" means, as to any Person, any law,
statute, treaty, rule, regulation, right, privilege, qualification, license or
franchise or determination of an arbitrator or a court or other Governmental
Authority or stock exchange, in each case applicable or binding upon such Person
or any of its property or to which such Person or any of its property is subject
or pertaining to any or all of the transactions contemplated or referred to
herein.

                  "REQUISITE COMPANY VOTE" shall mean (i) the approval and
ratification of the issuance of shares of Common Stock issuable upon the
conversion of the Note and upon exercise of the Warrant by a majority of holders
of Common Stock and Class B Common Stock, voting as a single class, that are
present in person or by proxy at a duly called meeting of Company's
stockholders, or (ii) the 20th day following the proper delivery by the Company
under Regulation 14C under the Exchange Act of an effective Information
Statement meeting the requirements of Schedule 14C under the Exchange Act that
contains the requisite information describing the action taken by the Written
Consent.

                  "RESTRICTED SUBSIDIARY" has the meaning set forth in the
Citicorp Facility.

                                       8
<PAGE>

                  "RESTRUCTURING" has the meaning set forth in the recitals to
this Agreement.

                  "SEC DOCUMENTS" has the meaning set forth in SECTION 3.28 of
this Agreement.

                  "SECURITIES ACT" means the Securities Act of 1933, as amended,
and the rules and regulations of the Commission thereunder.

                  "SENIOR NOTES" has the meaning set forth in the Citibank
Facility.

                  "SENIOR SECURITY DOCUMENTS" has the meaning set forth in the
Citibank Facility.

                  "SHAREHOLDER" has the meaning set forth in the Warrant
Agreement.

                  "SUBSIDIARIES" of a Person means (a) any corporation more than
50% of the outstanding securities having ordinary voting power of which shall at
the time be owned or controlled, directly or indirectly, by such Person or by
one or more of its Subsidiaries or by such Person and one or more of its
Subsidiaries, or (b) any company, partnership, association, joint venture or
similar business organization more than 50% of the ownership interests having
ordinary voting power of which shall at the time be so owned or controlled.
Unless otherwise expressly provided, all references herein to a "Subsidiary"
means a direct or indirect Subsidiary of the Company.

                  "SUBORDINATED NOTES" has the meaning set forth in the Citibank
Facility.

                  "TELECOMMUNICATIONS ASSETS" has the meaning set forth in the
Citicorp Facility.

                  "TELECOMMUNICATIONS BUSINESS" has the meaning set forth in the
Citibank Facility.

                  "TRANSACTION DOCUMENTS" mean, collectively, this Agreement,
the Note, the Warrant Agreement, the Warrant, the Registration Rights Agreement,
the Voting Agreement, the Letter Agreement, the Intercreditor and Collateral
Agency Agreement, the Junior Security Agreement and the other Junior Security
Documents.

                  "UNRESTRICTED SUBSIDIARY" has the meaning set forth in the
Citibank Facility.

                  "VENDOR" has the meaning set forth in the Citicorp Facility.

                  "VENDOR AGREEMENTS" has the meaning set forth in the Citicorp
Facility.

                  "VENDOR COLLATERAL" has the meaning set forth in the Junior
Security Agreement.

                                       9
<PAGE>

                  "VENDOR FINANCINGS" means the restructuring of amounts owed by
the Company or its Subsidiaries to certain of its Vendors (other than Nortel),
the aggregate amount of which shall not be less than US$230 million, including
the Bechtel Restructuring contemplated hereby.

                  "VENDOR OBLIGATIONS" has the meaning set forth in the Citicorp
Facility.

                  "VERIZON AGREEMENT" has the meaning set forth in the Citicorp
Facility.

                  "VERIZON DEBT AGREEMENT" has the meaning set forth in the
Citicorp Facility.

                  "VERIZON FINANCING" means the arrangements contained in the
Verizon Debt Agreement and agreements related thereto.

                  "VERIZON STOCKHOLDERS AGREEMENT" means the Stockholders
Agreement dated as of October 1, 2001 among the Company, Verizon Investments
Inc. and the other stockholders of the Company listed on the signature pages
thereto.

                  "VOTING AGREEMENT" means that certain Voting Agreement, dated
as of October 1, 2001 by and among the Company, Bechtel, Verizon Investments
Inc. and the stockholders party thereto.

                  "WARRANT" has the meaning set forth in the recitals to this
Agreement.

                  "WARRANT AGREEMENT" has the meaning set forth in the recitals
to this Agreement.

                  "WITHDRAWAL LIABILITY" has the meaning set forth in the
Citicorp Facility.

                  "WRITTEN CONSENT" means the duly authorized and executed
written consent in lieu of a meeting of the stockholders of the Company, dated
as of the Closing Date, and in the form prescribed by Section 228 of the
Delaware General Corporation Law, as amended, executed by the Metromedia
Company, a Delaware general partnership, John Kluge, Stuart Subotnick and
Stephen A. Garofalo, each in their capacities as stockholders of the Company and
collectively holding more than a majority of the Common Stock and Class B Common
Stock, voting as a single class, approving and authorizing the reservation for
issuance, issuance, sale and delivery of the shares of Common Stock issuable
upon conversion of the Note and issuable upon exercise of the Warrant for the
purposes of the applicable rules and regulations of NASDAQ, in the form of
EXHIBIT G attached hereto.

                                       10
<PAGE>

                                   ARTICLE II

                              BECHTEL RESTRUCTURING

                  2.1  RESTRUCTURING.  Subject to the terms and conditions
herein set forth, on the Closing Date:

                  (a) CASH PAYMENT. The Company shall pay to Bechtel by wire
transfer of immediately available funds the sum of US$9 million (the "CASH
PAYMENT"), which Cash Payment is being made in consideration of the settlement
of claims owed by MFN and/or its Subsidiaries to Bechtel under the Master
Services Agreement, as more particularly set forth in Section 6.2 hereof.

                  (b ISSUANCE OF NOTE. The Company and MFNS shall duly execute,
deliver and issue the Note to Bechtel, which Note is being issued in
consideration of the settlement of claims owed by MFN and/or its Subsidiaries to
Bechtel under the Master Services Agreement, as more particularly set forth in
Section 6.2 hereof.

                  (c) ISSUANCE OF WARRANT. The Company shall duly execute
the Warrant Agreement and deliver to Bechtel the Warrant(s) in accordance with
the terms thereof, which Warrant is being issued in consideration of Bechtel
entering into the transactions contemplated hereby and by the other Transaction
Documents.

                  (d) FEES. The Company shall pay by wire transfer of
immediately available funds, at the direction of Bechtel, all amounts required
to be paid by it pursuant to and in accordance with SECTION 5.8.

                  2.2 CLOSING. Unless this Agreement shall have terminated
pursuant to ARTICLE VIII, and subject to the satisfaction or waiver of the
conditions set forth in ARTICLE V , the closing of the Bechtel Restructuring
(the "CLOSING") shall take place at the New York offices of Paul, Weiss,
Rifkind, Wharton & Garrison, at 10:00 a.m., local time, on the first Business
Day following the date upon which the conditions set forth in ARTICLE V shall be
satisfied or waived in accordance with this Agreement, or at such other time,
place and date that the Company and Bechtel may mutually agree in writing (the
"CLOSING DATE"). On the Closing Date, the Company shall deliver or caused to be
delivered to Bechtel (a) the Cash Payment, (b) the duly executed Note and (c)
the duly issued Warrant.

                                  ARTICLE III

             REPRESENTATIONS AND WARRANTIES OF THE COMPANY AND MFNS

                  Each of the Company and MFNS hereby represent and warrant to
Bechtel that as of the date of this Agreement, except as set forth on a Schedule
of Exceptions furnished to Bechtel, which exceptions shall be deemed to be
representations and warranties as if made hereunder ("SCHEDULE OF EXCEPTIONS").

                                       11
<PAGE>

                  3.1 CORPORATE EXISTENCE AND POWER. Each of the Company and
MFNS (a) is a corporation duly organized, validly existing and in good standing
under the laws of the State of Delaware, (b) has all necessary power and
authority to own and operate its properties and assets and to carry on its
business as currently conducted and as currently proposed to be conducted as
described in the SEC Documents and (c) has the corporate power and authority to
execute, deliver and perform its respective obligations under this Agreement,
each of the other Transaction Documents and each Basic Documents and to issue
the Note, the Warrant and shares of Common Stock issuable upon conversion and
exercise thereof, respectively. Each of the Company and MFNS is duly qualified
and is authorized to transact business and is in good standing as a foreign
corporation in each jurisdiction in which the failure to so qualify would have a
Material Adverse Effect.

                  3.2 AUTHORIZATION. (a) All corporate action on the part of
each of the Company and MFNS, its respective officers, directors and
stockholders necessary for the due authorization, execution, consummation and
delivery of this Agreement, each of the other Transaction Documents and each
Basic Document, the performance of all obligations of each of the Company and
MFNS hereunder and thereunder and the due authorization, reservation for
issuance, sale, and delivery of the shares of Common Stock issuable upon
conversion of the Note and issuable upon exercise of the Warrant in accordance
with the Certificate of Incorporation, each of the Transaction Documents and
each Basic Document, when executed and delivered, will constitute valid and
legally binding obligations of each of the Company and MFNS, as applicable,
enforceable in accordance with their respective terms except (i) as limited by
applicable bankruptcy, insolvency, reorganization, moratorium, and other laws of
general application affecting enforcement of creditors' rights generally, (ii)
as limited by laws relating to the availability of specific performance,
injunctive relief, or other equitable remedies, and (iii) to the extent that the
indemnification provisions contained in the Registration Rights Agreement and
Warrant Agreement may be limited by applicable laws.

                  (b) The execution and delivery of this Agreement, each of the
other Transaction Documents and each Basic Document, the performance of all
obligations of each of the Company and MFNS hereunder and thereunder and the due
authorization, reservation for issuance, sale and delivery of the shares of
Common Stock issuable upon conversion of the Note and issuable upon exercise of
the Warrant (i) have been duly and validly approved by the stockholders of each
of the Company and MFNS by written consent in accordance with applicable law and
the certificate of incorporation and bylaws of the Company and MFNS and (ii)
have been duly and validly approved by the Board of Directors of each of the
Company and MFNS and such approvals are sufficient so that the restrictions on
business combinations set forth in Section 203 of the Delaware General
Corporation Law shall not apply to Bechtel or its assignees. Each of the Company
and MFNS shall take all action necessary to comply with Rule 14c-2 under the
Exchange Act as soon as practicable.

                  (c) The execution, delivery and performance by each of the
Company and MFNS of this Agreement, each other Transaction Document and all
instruments and documents to be delivered by the Company and/or MFNS in
connection therewith, the issuance of the Note and Warrant and the shares of
Common Stock issuable upon

                                       12
<PAGE>

conversion and exercise thereof, respectively, and the consummation of the other
transactions contemplated hereby and thereby (i) do not conflict with or result
in the breach or termination of, constitute a default under or accelerate any
performance required by any Basic Document or the Indentures, (ii) are not in
contravention of any provision of the Company's or MFNS' certificate of
incorporation or by-laws; (iii) will not violate any law or regulation, or any
order or decree of any court or governmental instrumentality to which the
Company or any of its Subsidiaries is a party or to which its assets are bound;
(iv) will not conflict with or result in the breach or termination of,
constitute a default under or accelerate any performance required by, any
indenture, mortgage, deed of trust, lease, agreement or other instrument to
which the Company or any of its Subsidiaries is a party or by which the Company,
any of its Subsidiaries or any of their respective properties is bound; and (v)
except for the Liens created in connection with the Verizon Debt Agreement, the
Citicorp Facility and the Vendor Agreements, will not result in the creation or
imposition of any Lien upon any of the property of the Company or any of its
Subsidiaries.

                  3.3 GOVERNMENTAL AUTHORIZATION; THIRD PARTY CONSENTS. No
approval, consent, compliance, exemption, licenses, authorization or other
action by, or notice to, or filing with, any Governmental Authority or any other
Person, and no lapse of a waiting period under a Requirement of Law, is
necessary or required in connection with (i) the execution, delivery or
performance (including, without limitation, issuance and delivery of the Note
and the Warrant and the issuance and delivery of the shares of Common Stock
issuable upon conversion or exercise thereof, respectively) by, or enforcement
against, the Company or MFNS of this Agreement and the other Transaction
Documents or the transactions contemplated hereby and thereby or (ii) the
legality, validity, binding effect or enforceability of the Transaction
Documents, except for the filing of Uniform Commercial Code financing statements
and the other similar filings to protect security interests and such as are
listed on SCHEDULE 4.01 (e) of the Citicorp Facility.

                  3.4 COMPLIANCE WITH LAWS; PERMITS. Neither the Company nor any
of its Subsidiaries is in violation of any applicable statute, rule, regulation,
Order, or restriction of any domestic or foreign government or any
instrumentality or agency thereof in respect of the conduct of its business or
the ownership of its properties, which violation would have a Material Adverse
Effect.

                  3.5 LICENSES.

                  (a) REQUIRED LICENSES. As of the date hereof, except for the
Licenses described in SCHEDULE 4.01(t) of the Citicorp Facility, there are no
Licenses, which are required for the operation of the business of the Company or
any Restricted Subsidiary, including Licenses issuable under the United States
Federal Communications Act of 1934, as amended. The Licenses described in
SCHEDULE 4.01(t) of the Citicorp Facility are adequate and sufficient for the
construction, ownership and operation of the Telecommunications Assets of the
Company and its Restricted Subsidiaries and neither the Company nor any
Restricted Subsidiary is in default in any manner under any provision of any
such License, where such default has had or could reasonably be expected
(individually or in the aggregate) to have a Material Adverse Effect.

                                       13
<PAGE>

                  (b) COMPLIANCE. Except as disclosed in SCHEDULE 4.01(t) of the
Citicorp Facility, the Company and each of its Restricted Subsidiaries is in
compliance with the terms of each of the Licenses under which it enjoys rights
or privileges and has timely filed or caused to be filed all renewal
applications with respect to the Licenses, no protests or competing applications
have been filed with respect to such renewal applications and nothing has come
to the attention of the Company or any of its Restricted Subsidiaries (after due
inquiry) that would lead them to conclude that such renewal applications would
not be granted in the ordinary course, in each case other than any thereof that
has not had and could not reasonably be expected (individually or in the
aggregate) to have a Material Adverse Effect. The Company and each of its
Restricted Subsidiaries is authorized under applicable law and the rules and
regulations promulgated thereunder to continue to provide the services which are
the subject of such renewal applications during the pendency thereof.

                  (c) NO RATE REGULATION. Except as disclosed in SCHEDULE
4.01(t) of the Citicorp Facility, the business and operations conducted and
proposed to be conducted by each Obligor in relation to its business are not
regulated by any federal, state or provincial utility or rate-regulating
commission.

                  3.6 PRIVATE LICENSES. The Private Licenses of the Company and
its Restricted Subsidiaries are adequate and sufficient for the construction,
ownership and operation of the Telecommunications Assets of the Company and its
Restricted Subsidiaries and neither the Company nor any Restricted Subsidiary is
in default in any manner under any provision of any Private License to which it
is a party or by which it or any of its assets may be bound, where such default
has had or could reasonably be expected (individually or in the aggregate) to
have a Material Adverse Effect.

                  3.7 FRANCHISES. Each Franchise of the Company and each of its
Restricted Subsidiaries is in full force and effect pursuant to each statute,
regulation, agreement or instrument of each jurisdiction set forth on SCHEDULE
4.01(u) of the Citicorp Facility, was lawfully issued pursuant to the rules and
regulations of such jurisdiction and authorizes the Company and each such
Restricted Subsidiary to operate such Franchise, and no other or further
approval, filing or other action of any Governmental Authority is or will be
necessary or advisable in order to permit the operation by the Company or any
Restricted Subsidiary of its Telecommunications Business in accordance with the
terms thereof. The Company and its Restricted Subsidiaries are in compliance
with all material terms and conditions of each of their respective Franchises
and no event has occurred or exists which permits or, after the giving of notice
or the lapse of time or both, would permit the revocation or termination of any
such Franchise, other than where any such non-compliance or revocation or
termination (i) has not had and could not reasonably be expected (individually
or in the aggregate) to have a Material Adverse Effect or (ii) has not resulted
in a notification of non-compliance or revocation or termination by or to any
parties to such Franchises. No Unrestricted Subsidiary owns or has rights to any
Franchise necessary for the ongoing operations of the Company and its Restricted
Subsidiaries or their respective Telecommunications Business.

                                       14
<PAGE>

                  3.8 COMPLIANCE WITH OTHER INSTRUMENTS. Neither the Company nor
MFNS is in violation or default of any provision of its Certificate of
Incorporation or Bylaws or, except as has not had or could not reasonably be
expected (individually or in aggregate) to have a Material Adverse Effect, of
any provision of any Lien, Indenture, Material Agreement or instrument to which
it is a party or by which it is bound or, to its knowledge, of any federal or
state judgment, Order, statute, rule, regulation or restriction applicable to
the Company or its Subsidiaries. The execution, delivery, and performance by
each of the Company and MFNS of this Agreement and any other Transaction
Documents, and the consummation of the transactions contemplated hereby and
thereby, will not result in any such violation or be in material conflict with
or constitute, with or without the passage of time or giving of notice, either a
material default under any such provision or an event that results in the
creation of any Lien upon any assets of either the Company or its Subsidiaries
or the suspension, revocation, impairment, forfeiture, or non-renewal of any
material permit, license, authorization, or approval applicable to either the
Company or its Subsidiaries, their respective businesses or operations, or any
of their respective assets or properties.

                  3.9 NO MATERIAL MISSTATEMENTS. The information, reports,
financial statements, exhibits and schedules furnished in writing by or on
behalf of the Company to the Collateral Agent or Bechtel in connection with the
negotiation, preparation or delivery of this Agreement, each of the other
Transaction Documents and each Basic Document or included herein or therein or
delivered pursuant hereto or thereto, when taken as a whole, do not contain any
untrue statement of material fact or omit to state any material fact necessary
to make the statements herein or therein, in light of the circumstances under
which they were made, not misleading, other than a material fact the effect of
which is favorable to the Company; PROVIDED that to the extent any such
information, report, financial statement, exhibit or schedule was based upon or
constitutes a forecast, projection or expression of opinion, the Company
represents only that it acted in good faith and utilized reasonable assumptions
and due care in the preparation of such information, report, financial
statement, exhibit or schedule. All written information furnished after the date
hereof by the Company and its Subsidiaries to the Collateral Agent and Bechtel
in connection with this Agreement, each of the other Transaction Documents and
each Basic Document and the transactions contemplated hereby and thereby will be
true, complete and accurate in every material respect, or (in the case of
projections) based on reasonable estimates, on the date as of which such
information is stated or certified. There is no fact known to the Company that
has had or could reasonably be expected (individually or in the aggregate) to
have a Material Adverse Effect that has not been disclosed herein, in the other
Transaction Documents, in any document related to the Restructuring or in a
report, financial statement, exhibit, schedule, disclosure letter or other
writing furnished to the Collateral Agent or Bechtel for use in connection with
the transactions contemplated hereby or thereby.

                  3.10 PERFECTION AND PRIORITY OF LIENS. At all times after the
execution of the Junior Security Documents, the Junior Security Documents
create, in favor of Bechtel, as security for the obligations purported to be
secured thereby, a legal, valid and enforceable perfected security interest or
Lien in all of the Vendor Collateral of Bechtel,

                                       15
<PAGE>

subject to the terms of the Intercreditor and Collateral Agency Agreement,
superior to and prior to the rights of all third persons (other than the holders
of the notes issued pursuant to the Citicorp Facility) and subject to no Liens
except Liens expressly permitted by the terms of the Note. The Company or MFNS
has (or, on and after the time it executes the respective Junior Security
Document, will have) good and marketable title to all items of Vendor Collateral
(or, as the case may be, collateral) covered by such Junior Security Document
free and clear of all Liens except Liens expressly permitted by the terms of the
Note. The security interests created in favor of Bechtel under the Junior
Security Agreement constitute perfected security interests in the Vendor
Collateral under and as defined in the Junior Security Agreement and owned by
the Company or its Subsidiaries on any date on which this representation and
warranty is made or deemed made, subject to no security interests of any other
Person other than the security interests of the holders of the notes issued
pursuant to the Citicorp Facility in accordance with the terms of the
Intercreditor and Collateral Agency Agreement.

                  3.11 VALID ISSUANCE OF COMMON STOCK. The shares of Common
Stock issuable upon conversion of the Note and upon exercise of the Warrant,
when issued and delivered in accordance with the terms of this Agreement and the
Note, the Warrant Agreement and/or the Warrant, applicable, for the
consideration expressed herein and therein will be duly and validly issued,
fully paid, and nonassessable, and will be free of all Liens and restrictions on
transfer other than restrictions on transfer under this Agreement and the other
Transaction Documents and all applicable state and federal securities laws. The
conversion of the Note and the exercise of the Warrant, in each case for shares
of Common Stock will not be subject to any preemptive rights or rights of first
refusal that have not been properly waived or complied with.

                  3.12 CAPITALIZATION AND VOTING RIGHTS. (a) As of September 28,
2001, the authorized capital stock of the Company consisted of (i) 2,404,031,240
shares of Common Stock, of which 548,575,321 shares were issued and outstanding;
(ii) 522,254,782 shares of Class B Common Stock, of which 67,538,544 shares were
issued and outstanding; and (iii) 20,000,000 shares of Preferred Stock, US$0.01
par value per share, none of which were issued and outstanding. All of such
issued and outstanding shares are validly issued, fully paid and non-assessable.
No shares of capital stock are held by the Company as treasury stock as of the
date of this Agreement and no shares of capital stock of the Company shall be
held by the Company as treasury stock as of the Closing. The Company has agreed
to issue 87,811,368 shares of Common Stock in connection with the Restructuring,
all of which when issued will be validly issued, fully paid and non-assessable.
Except for the Note, the Warrant or as otherwise disclosed in SCHEDULE 3.12, the
Company does not have nor after giving effect to the Restructuring will have,
outstanding any Convertible Securities or Options exercisable or convertible
into or exchangeable for any interests or other equity rights of the Company or
its Subsidiaries, nor shall it have outstanding any agreements providing for the
issuance (contingent or otherwise) of, or any calls, commitments or claims of
any character relating to, any interests or equity rights of the Company or its
Subsidiaries or Convertible Securities exercisable or convertible into or
exchangeable for any interests or equity rights of the Company or its
Subsidiaries.

                                       16
<PAGE>

                  (b) Other than this Agreement or as otherwise disclosed in
SCHEDULE 3.12(b), there is not in effect on the date hereof any agreement by the
Company pursuant to which any holders of debt or equity securities of the
Company have a right to cause the Company to register such securities under the
Securities Act. None of the agreements listed on SCHEDULE 3.12(b) contain any
provision that conflict or are inconsistent in any material respect with the
rights granted under the Registration Rights Agreement or the Warrant Agreement.
Except for the (i) Verizon Stockholders Agreement, (ii) voting agreements with
respect to the Citicorp Facility and the Nortel Agreement entered into in
connection with the Restructuring, and (iii) warrant agreements with respect to
Other Warrants, there is not in effect on the date hereof any agreement to which
the Company or (to its knowledge) any of its Shareholders is a party relating to
the voting, transfer or sale of such securities.

                  3.13 SUBSIDIARIES. Set forth on SCHEDULE 4.01(i) of the
Citicorp Facility is a complete and accurate list of all Subsidiaries of the
Company as of the date hereof, showing as of such date (as to each such
Subsidiary) the jurisdiction of its organization, whether or not such Subsidiary
is a Restricted Subsidiary or Unrestricted Subsidiary, the number of shares of
each class of Capital Stock authorized, and the number outstanding and the
percentage of the outstanding shares or interests of each such class owned
(directly or indirectly) by the Company and the number of shares covered by all
outstanding options, warrants, rights of conversion or purchase and similar
rights. All of the outstanding Capital Stock of all of such Subsidiaries have
been validly issued, are fully paid and non-assessable and are owned (directly
or indirectly) by the Company or one or more of its Subsidiaries free and clear
of all Liens, except those created by the Senior Security Documents and those
listed in SCHEDULE 4.01(i) of the Citicorp Facility.

                  3.14 AGREEMENTS.

                  (a) NO DEFAULT UNDER AGREEMENTS, ETC. Neither the Company nor
any Restricted Subsidiary is in default in any manner under any provision of any
agreement or instrument evidencing Indebtedness, or any other agreement or
instrument to which it is a party or by which it or any of its properties or
assets are or may be bound, where such default has had or could reasonably be
expected (individually or in the aggregate) to have a Material Adverse Effect.
The consummation by the Company of the transactions contemplated hereby will not
trigger any redemption events or result in the creation of any Liens under any
provision of any agreement or instrument evidencing Indebtedness, or any other
agreement or instrument to which it is a party or by which it or any of its
properties or assets are or may be bound.

                  (b) MATERIAL AGREEMENTS. Set forth on SCHEDULE 4.01(k) of the
Citicorp Facility is a list of agreements (other than those referred to in
clauses (a) through (e) of the definition of the term "MATERIAL AGREEMENT") to
which the Company or any of its Restricted Subsidiaries is a party that are
material to the business, assets, operations, financial condition or liabilities
of the Company and its Restricted Subsidiaries, taken as a whole. The Company
has heretofore delivered to the Bechtel, true and complete copies of each of the
Material Agreements. Each of the Material Agreements is in full force and

                                       17
<PAGE>

effect and neither the Company nor any of its Subsidiaries nor any of the
counterparties under any of such Material Agreements, (x) is in default of any
of its respective obligations thereunder where such default has had or could
reasonably be expected (individually or in the aggregate) to have a Material
Adverse Effect or (y) has delivered or received notification of any default or
material deficiency under any such Material Agreement.

                  (c) RESTRICTIVE OR BURDENSOME AGREEMENTS. As of the date
hereof, other than as set forth in SCHEDULE 4.01(k) of the Citicorp Facility or
on the Schedule to be delivered on or before the Closing Date pursuant to
SECTION 6.08 of the Citicorp Facility, neither the Company nor any Restricted
Subsidiary is subject to any indenture, agreement, instrument or other
arrangement of the type described in SECTION 6.08 of the Citicorp Facility, nor
any agreement that imposes burdensome requirements upon the Company or any
Restricted Subsidiary that, singly or in the aggregate, would be reasonably
likely (individually or in the aggregate) to result in a Material Adverse
Effect.

                  3.15 LITIGATION. (a) There is no action, suit, proceeding or
investigation pending or, to the knowledge of either the Company or MFNS,
threatened against the Company or any of its Subsidiaries before any
Governmental Authority seeking to enjoin or otherwise involving the transactions
contemplated by this Agreement or the other Transaction Documents.

                  (b) Except as set forth on SCHEDULE 3.15, there are no legal
or arbitral proceedings or any proceedings by or before any Governmental
Authority, now pending or (to the knowledge of the Company) threatened against
the Company or MFNS or any of their Subsidiaries, which could reasonably be
expected to have a Material Adverse Effect.

                  3.16 TITLE TO PROPERTY, ASSETS AND LEASES.

                  (a) TITLE TO PROPERTY. Each of the Company and its Restricted
Subsidiaries has good title to, or valid leasehold interests in, all of its
properties and assets which are material to the Company and its Restricted
Subsidiaries, taken as a whole, except for minor defects in title that do not
materially interfere with its ability to conduct its business as currently
conducted or to utilize such properties and assets for their intended purposes.
All such material properties and assets are free and clear of Liens, other than
Liens expressly permitted by SECTION 6.02 of the Citicorp Facility.

                  (b) POSSESSION UNDER LEASES. Each of the Company and its
Restricted Subsidiaries has complied with all obligations under all leases which
are material to the Company and its Restricted Subsidiaries, taken as a whole,
to which it is a party and all such leases are in full force and effect, except
where failure to do so or failure of such leases to be in full force and effect
has not had and could not reasonably be expected (individually or in the
aggregate) to have a Material Adverse Effect. Each of the Company and its
Restricted Subsidiaries enjoys peaceful and undisturbed possession under all
such leases, except where failure to do so has not had and could not reasonably
be expected (individually or in the aggregate) to have a Material Adverse
Effect.

                                       18
<PAGE>

                  (c) INTELLECTUAL PROPERTY. Each of the Company and its
Restricted Subsidiaries owns, or is licensed to use, all trademarks, tradenames,
copyrights, patents and other intellectual property material to its business,
and the use thereof by the Company and its Restricted Subsidiaries does not
infringe upon the rights of any other Person, except for any such infringements
that, individually or in the aggregate, could not reasonably be expected
(individually or in the aggregate) to result in a Material Adverse Effect.

                  3.17 ENVIRONMENTAL MATTERS. The operations and properties of
the Company, MFNS and each of their respective Restricted Subsidiaries are in
compliance in all material respects with all Environmental Laws, all necessary
Environmental Permits have been obtained and are in effect or have been applied
for in order for the Company, MFNS and their respective Restricted Subsidiaries
to conduct their respective operations and to own their respective properties,
the Company, MFNS and their Restricted Subsidiaries are in compliance in all
material respects with all such issued Environmental Permits, no circumstances
exist that could (x) form the basis of an Environmental Claim that could
reasonably be expected (individually or in the aggregate) to have a Material
Adverse Effect, or (y) cause any such property to be subject to any restrictions
on ownership, occupancy, use or transferability under any Environmental Law that
has had or could reasonably be expected (individually or in the aggregate) to
have a Material Adverse Effect, and, to the best knowledge of the Company, MFNS
and their respective Restricted Subsidiaries, no investigation (other than
routine investigations) of any such operation or property has been or is being
conducted by any Governmental Authority with respect to the enforcement of any
Environmental Law other than investigations which have not had and could not
reasonably be expected (individually or in the aggregate) to have a Material
Adverse Effect.

                  3.18 TAX RETURNS. Each of the Company, MFNS and the Restricted
Subsidiaries has filed or caused to be filed all material foreign, federal,
state and other tax returns, extensions or materials required to have been filed
by it and has paid or caused to be paid all taxes shown on such returns to be
due and payable by it and all assessments received by it, except (x) taxes and
assessments that are being contested in good faith by appropriate proceedings
and for which it shall have set aside on its books adequate reserves in
accordance with GAAP and (y) taxes and assessments the failure to pay which has
not had and could not reasonably be expected (individually or in the aggregate)
to result in a Material Adverse Effect.

                  3.19 PENSION PLANS. Each of the Company, MFNS and their
respective ERISA Affiliates is in compliance in all material respects with the
applicable provisions of ERISA and the Code and the regulations and published
interpretations thereunder, except where non-compliance has not had and could
not reasonably be expected (individually or in the aggregate) to have a Material
Adverse Effect. No ERISA Event has occurred or is reasonably expected to occur
that, when taken together with all other such ERISA Events, could reasonably be
expected to result in material liability of the Company, MFNS or any of their
respective ERISA Affiliates, except where such liability has not had and could
not reasonably be expected (individually or in the aggregate) to have a Material
Adverse Effect.

                                       19
<PAGE>

                  3.20 INVESTMENT COMPANY ACT. Neither the Company nor MFNS is
an "investment company", nor a company "controlled by" an "investment company",
within the meaning of the Investment Company Act of 1940, as amended.

                  3.21 PUBLIC UTILITY HOLDING COMPANY ACT. Neither the Company
nor MFNS is a "holding company", or an "affiliate" of a "holding company" or a
"subsidiary company" of a "holding company", within the meaning of the Public
Utility Holding Company Act of 1935, as amended.

                  3.22 FEDERAL RESERVE REGULATIONS. Neither the Company, MFNS
nor any Restricted Subsidiary is engaged principally, or as one of its important
activities, in the business of extending credit for the purpose of buying or
carrying Margin Stock. No part of the proceeds of the Note will be used by the
Company, MFNS or any Restricted Subsidiary, whether directly or indirectly, and
whether immediately, incidentally or ultimately, for any purpose that violates
Regulation T, U or X.

                  3.23 NO DEFAULT. No event has occurred and is continuing, or
would result from the issuance of the Note or the Warrant or from the
application of the proceeds therefrom, that constitutes a Default or an Event of
Default under the Note.

                  3.24 INSURANCE. SCHEDULE 4.01(r) of the Citicorp Facility sets
forth a true, complete and correct description of all material insurance
maintained by the Company (including insurance maintained by the Company for its
Restricted Subsidiaries) as of the date hereof. As of the date hereof, such
insurance is in full force and effect and all premiums, which have become due
and payable have been duly paid. Each of the Company and its Restricted
Subsidiaries maintains insurance in such amounts and covering such risks and
liabilities as are in accordance with normal industry practice.

                  3.25 SOLVENCY. Immediately after the consummation of the
Transactions to occur on the Closing Date and immediately following the issuance
of the Note and the consummation of the Restructuring and after giving effect to
the application of the proceeds thereof, and taking into account all rights of
indemnity, subrogation and contribution of the Obligors under applicable law,
each Obligor is Solvent.

                  3.26 PROJECTED FINANCIAL STATEMENTS. The projected financial
statements delivered pursuant to SECTION 5.14 have been prepared in good faith,
based on estimates and assumptions that the Company believes are fair and
reasonable at the time such projections have been furnished to Bechtel.

                  3.27 NO MATERIAL ADVERSE CHANGE. Since December 31, 2000,
except as set forth in the Form 10-Q for the Company as at June 30, 2001, there
has been no material adverse change in the Condition of the Company.

                  3.28 SEC DOCUMENTS; FINANCIAL STATEMENTS. The Company has
filed in a timely manner all documents that the Company was required to file
with the Commission under Sections 13, 14(a) and 15(d) of the Exchange Act,
since its initial public offering. As of their respective filing dates, all
documents filed by the Company

                                       20
<PAGE>

with the Commission ("SEC DOCUMENTS") complied in all material respects with the
requirements of the Exchange Act or the Securities Act, as applicable. None of
the SEC Documents as of their respective dates contained any untrue statement of
a material fact or omitted to state a material fact required to be stated
therein or necessary to make the statements made therein, in light of the
circumstances under which they were made, not misleading. The financial
statements of the Company included in the SEC Documents (the "FINANCIAL
STATEMENTS") comply as to form in all material respects with applicable
accounting requirements and with the published rules and regulations of the
Commission with respect thereto. The Financial Statements have been prepared in
accordance with GAAP and fairly present the consolidated financial position of
the Company and its Subsidiaries at the dates thereof and the consolidated
results of their operations and consolidated cash flows for the periods then
ended (subject, in the case of unaudited statements, to the lack of full
footnote disclosure and to normal, recurring adjustments). Since December 31,
2000, neither the Company nor any of its Subsidiaries has incurred any material
liabilities or obligations (whether absolute, accrued, fixed, contingent,
liquidated, unliquidated or otherwise and whether due or to become due) of any
nature, except liabilities, obligations or contingencies (a) which are reflected
on the audited balance sheet of the Company and its Subsidiaries as at December
31, 2000, (including the notes hereto), or (b) which (i) were incurred in the
ordinary course of business after December 31, 2000 and consistent with past
practices, or (ii) are disclosed or reflected in the SEC Documents filed after
December 31, 2000. Since March 6, 2000, the Company has timely filed with the
SEC all forms, reports and other documents required to be filed prior to the
date hereof, and no Subsidiary of the Company has filed, or been required to
file, any form, report or other document with the SEC, in each case, pursuant to
the Securities Act, the Exchange Act or the rules and regulations thereunder.

                  3.29 PRIVATE OFFERING. No form of general solicitation or
general advertising was used by the Company, MFNS or its representatives in
connection with the offer or sale of the Note or Warrant. No registration of the
Note or Warrant, pursuant to the provisions of the Securities Act or any state
securities or "blue sky" laws, will be required by the offer, sale or issuance
of the Note or Warrant. Each of the Company and MFNS agree that neither it, nor
anyone acting on its behalf, shall offer to sell the Note or Warrant or any
other securities of the Company so as to require the registration of the Note or
Warrant pursuant to the provisions of the Securities Act or any state securities
or "blue sky" laws, unless such Note or Warrant or other securities are so
registered.

                  3.30 TERMS OF CERTAIN OTHER DEBT AGREEMENTS. No financing,
restructuring or other arrangement relating to the Restructuring, other than the
security granted to the parties to the Citicorp Facility in accordance with the
terms thereof, as the same are in effect as of the Closing Date, contains or
provides for terms or conditions which, when taken as a whole and excluding
consideration of payment terms and maturity dates, are more favorable than the
terms and provisions contained in this Agreement and the Transaction Documents.

                  3.31 AMOUNTS OWED UNDER THE MASTER SERVICES AGREEMENT. As of
the Closing Date, the best estimate of the Company as to the aggregate amount of
indebtedness or other obligations of the Company Parties due and owing to the
Bechtel

                                       21
<PAGE>

Parties under the Master Services Agreement is US$98 million (subject to any
additional amounts required to be paid in accordance with SECTION 6.3 hereof),
which amount may be adjusted in accordance with the terms of the Letter
Agreement but which amount is not subject to any setoff, counterclaim,
recoupment, deduction, abatement, suspension, diminution, reduction, defense or
other right which the Company Parties may have against the Bechtel Parties for
any reason whatsoever arising under or pursuant to the Master Services Agreement
or otherwise relating to the purchase of goods or services from the Bechtel
Parties.

                  3.32 PURCHASE MONEY INDEBTEDNESS. The Indebtedness evidenced
by the Note constitutes "Purchase Money Indebtedness" as such term is defined in
each of the Indentures.

                  3.33 OTHER RESTRUCTURING AGREEMENTS. Neither the Company nor
any of its Subsidiaries have, directly or indirectly, entered into any
transaction or series of related transactions (or any amendments, modifications
or supplements thereto) in connection with the Restructuring with any Person on
terms (except with respect to the terms relating to security interest granted to
the lenders under the Citicorp Facility) that, in the aggregate, are less
favorable to the Company or its Subsidiaries than the transactions contemplated
by the Transaction Documents.

                  3.34 RESTRICTIONS ON COLLATERAL. The Licenses, Franchises and
Private Licenses to which the Company and MFNS are a party that contain
provisions prohibiting the creation of a security interest on assets of the
Company and MFNS do not, individually or in the aggregate, prohibit in any
material respect Liens being granted under the Junior Security Agreement with
respect to assets of the Company or MFNS all or any portion of the cost of
engineering, construction, installation, acquisition, development or improvement
of which was financed by the Junior Secured Obligations of Bechtel.

                  3.35 WRITTEN CONSENT. The shares of Common Stock and Class B
Stock held by the Persons that have executed the Voting Agreement, and that are
represented by, the Written Consent equal more than a majority of the aggregate
of the Common Stock and Class B Stock outstanding and entitled to vote at a
meeting of the Company's stockholders as of the date thereof and otherwise
represent a sufficient amount of shares of Common Stock and Class B Stock to
approve the matters referred to in the Written Consent.

                  3.36 BROKERS. All negotiations relative to this Agreement and
the other Transaction Documents have been carried out by the Company or MFNS
directly with Bechtel without the intervention of any Person on behalf of the
Company or MFNS in such manner as to give rise to any valid claim by any Person
against Bechtel or any of its Subsidiaries for a finder's fee, brokerage
commission or similar payment.

                                       22
<PAGE>

                                   ARTICLE IV

                    REPRESENTATIONS AND WARRANTIES OF BECHTEL

                  Bechtel hereby represents and warrants to the Company as
follows, as of the date of this Agreement and as of the Closing Date:

                  4.1 PURCHASE FOR OWN ACCOUNT. The Note and Warrant to be
issued to Bechtel pursuant to this Agreement and the Warrant Agreement is being
or will be acquired for its own account and with no intention of distributing or
reselling such Note or Warrant or any part thereof in any transaction that would
be in violation of the securities laws of the United States of America, or any
state, without prejudice, however, to the rights of Bechtel at all times to sell
or otherwise dispose of all or any part of such Warrant or Note (or the shares
of Common Stock into which the Note is convertible and for which such Warrant is
exercisable) under an effective registration statement under the Securities Act,
or under an exemption from such registration available under the Securities Act,
and subject, nevertheless, to the disposition of Bechtel's property being at all
times within its control. If Bechtel should in the future decide to dispose of
any of such Note or Warrant (and the shares of Common Stock into which the Note
is convertible and for which such Warrant is exercisable), Bechtel understands
and agrees that it may do so only in compliance with the Securities Act and
applicable state securities laws, as then in effect. Bechtel agrees to the
imprinting, so long as required by law, of a legend on its Note and shares of
Common Stock issuable upon conversion thereof to the following effect:

         THE SECURITIES REPRESENTED BY THIS NOTE HAVE NOT BEEN REGISTERED UNDER
         THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR THE SECURITIES
         LAWS OF ANY STATE. THE SECURITIES MAY NOT BE TRANSFERRED EXCEPT
         PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND
         APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION
         FROM THE REGISTRATION REQUIREMENTS OF SUCH ACT AND SUCH LAWS OR
         PURSUANT TO A WRITTEN OPINION OF COUNSEL FOR THE COMPANY THAT SUCH
         REGISTRATION IS NOT REQUIRED.

                  4.2 RESTRICTED SECURITIES. Bechtel understands that the
Warrant and the Note will not be registered at the time of their issuance under
the Securities Act for the reason that the sale provided for in this Agreement
is exempt pursuant to Section 4(2) of the Securities Act and that the reliance
of the Company on such exemption is predicated in part on Bechtel's
representations set forth herein.

                  4.3 ACCREDITED INVESTOR. Bechtel is an "Accredited Investor"
within the meaning of Rule 501 of Regulation D under the Securities Act, as
presently in effect, Bechtel is an experienced investor in securities and
acknowledges that it can bear the economic risk of its investment and has such
knowledge and experience in financial and business matters that it is capable of
evaluating the merits and risks of this investment.

                                       23
<PAGE>

                  4.4 EXISTENCE AND POWER. Bechtel (a) is a corporation duly
organized and validly existing under the laws of the jurisdiction of its
formation and (b) has the requisite corporate power and authority to execute,
deliver and perform its obligations under this Agreement and each of the other
Transaction Documents.

                  4.5 AUTHORIZATION; NO CONTRAVENTION. The execution, delivery
and performance by Bechtel of this Agreement and each of the other Transaction
Documents and the transactions contemplated hereby and thereby (a) have been
duly authorized by all necessary corporate action and (b) do not contravene the
terms of Bechtel's organizational documents, or any amendment thereof.

                  4.6 BINDING EFFECT. This Agreement and each of the other
Transaction Documents have been duly executed and delivered by Bechtel and
constitute the legal, valid and binding obligations of Bechtel, enforceable
against it in accordance with their respective terms, except as enforceability
may be limited by applicable bankruptcy, insolvency, reorganization, fraudulent
conveyance or transfer, moratorium or similar laws affecting the enforcement to
creditors' rights generally or principles relating to enforceability (regardless
of whether considered in a proceeding at law or in equity).

                  4.7 DISCLOSURE OF INFORMATION. Bechtel has received and
reviewed all of the Company's registration statements, proxy statements,
periodic filings and other reports filed with the Securities and Exchange
Commission, including the Company's Quarterly Report on Form 10-Q for the period
ended June 30, 2001. Bechtel has had an opportunity to ask questions and receive
answers from the Company regarding the business, properties, and financial
conditions of the Company.

                                   ARTICLE V

                          CONDITIONS TO THE OBLIGATION
                              OF BECHTEL TO CLOSE

                  The obligations of Bechtel to consummate the Bechtel
Restructuring, and to accept the Cash Payment, the Warrant and the Note at the
Closing and to perform any obligations hereunder shall be subject to the
fulfillment to Bechtel's satisfaction, on or prior to the Closing, of each of
the following conditions, unless otherwise waived:

                  5.1 REPRESENTATION AND WARRANTIES. The representations and
warranties of the Company and MFNS contained in ARTICLE III hereof shall be true
and correct in all material respects (except for any such representations and
warranties which are qualified by their terms by a reference to materiality,
which representation as so qualified shall be true and correct in all respects)
at and on the Closing Date as if made at and on such date.

                                       24
<PAGE>

                  5.2 COMPLIANCE WITH THIS AGREEMENT. The Company shall have
performed and complied with all of its agreements set forth herein that are
required to be performed by the Company on or before the Closing Date.

                  5.3 WARRANT AGREEMENT, NOTE AND OTHER DOCUMENTATION. Each
Transaction Document shall be executed and delivered to Bechtel, in each case
duly executed by each of the intended parties thereto, together with evidence
satisfactory to Bechtel that its security interest in the Vendor Collateral has
been properly perfected in accordance with the terms of the Intercreditor and
Collateral Agency Agreement.

                  5.4 ORGANIZATIONAL DOCUMENTS, ETC. For each of the Company and
MFNS, such documents and certificates as Bechtel shall have reasonably requested
relating to the organization, existence and good standing of each of the Company
and MFNS, the authorization of the Restructuring, including the Bechtel
Restructuring, and any other legal matters relating to each of the Company and
MFNS, this Agreement, the other Transactions Documents or the Restructuring, all
in form and substance reasonably satisfactory to the Bechtel and its counsel.

                  5.5 FINANCIAL OFFICER'S CERTIFICATES. A certificate of a
Financial Officer of each of the Company and MFNS to the effect that:

                           (i) the representations and warranties contained in
                  each Transaction Document are true and correct on and as of
                  the Closing Date, before and after giving effect to the
                  transactions contemplated hereby, as though made on and as of
                  such date (or, if any such representation or warranty is
                  expressly stated to have been made as of a specific date, as
                  of such specific date);

                           (ii) no event has occurred and is continuing that
                  constitutes a Default or an Event of Default under the terms
                  of the Note; and

                           (iii) as of the Closing Date and following the
                  issuance of the Note and after giving effect to the
                  application of the proceeds thereof, each of the Company and
                  MFNS is Solvent.

                  Such certificate shall also state that the financial
projections and underlying assumptions upon which the conclusions set forth in
such analysis in clause (iii) above were based are, on the Closing Date, fair
and reasonable in the opinion of the Company and accurately computed and that
the portion of contingent liabilities of the Company that have been included for
purposes of the above determinations shall be the amount of such contingent
liabilities that, in light of all facts and circumstances existing at such time,
could reasonably be expected to become actual matured liabilities of the Issuer.

                  5.6 CONSENTS. Evidence reasonably acceptable to Bechtel of
receipt of all governmental and third party consents (including, without
limitation, a duly executed copy of the Written Consent) and approvals necessary
in connection with this Agreement,

                                       25
<PAGE>

the other Transaction Documents and the Restructuring and that the same remain
in effect.

                  5.7 OPINIONS OF COUNSEL TO THE OBLIGORS. An opinion of (i)
Paul, Weiss, Rifkind, Wharton & Garrison, dated the Closing Date, in the form of
EXHIBIT F-1 to this Agreement, (ii) an opinion of Akin, Gump, Strauss, Hauer &
Feld, L.L.P., dated the Closing Date, in the form of EXHIBIT F-2 to this
Agreement and (iii) a favorable opinion of the General Counsel for the Company,
covering such matters not covered by the opinion of Paul, Weiss, Rifkind,
Wharton & Garrison or Akin, Gump, Strauss, Hauer & Feld, L.L.P. and as is
satisfactory to Bechtel.

                  5.8 FEES. Evidence reasonably acceptable to Bechtel that the
Company shall have paid all fees required to be paid, and all expenses for which
invoices have been presented, on or before the Closing Date (including the
reasonable fees and expenses of Shearman & Sterling, counsel to Bechtel) and to
the extent that statements for such fees and expenses have been delivered to the
Company.

                  5.9 ISSUANCE OF CONVERTIBLE DEBT OR EQUITY. Evidence
reasonably acceptable to Bechtel that the Company shall have received net cash
proceeds in an amount at least equal to US$180,000,000 from the issuance at par
of unsecured convertible debt or equity, pursuant to agreements (including all
related shareholder, registration right and other agreements) in form and
substance satisfactory to Bechtel, with the terms and conditions applicable to
such debt or equity being satisfactory in form and substance to Bechtel,
including the condition that all the net cash proceeds therefrom shall be
available for general corporate purposes of the Company.

                  5.10 VERIZON DEBT AGREEMENT. Evidence reasonably acceptable to
Bechtel that the Company shall have received net cash proceeds in an amount at
least equal to US$50,000,000 from the issuance at par of secured Indebtedness,
pursuant to agreements (including all related shareholder, registration right
and other agreements) in form and substance satisfactory to Bechtel, with the
terms and conditions applicable to such Indebtedness being satisfactory in form
and substance to Bechtel, it being understood that such Indebtedness shall be
(i) incurred by the Company to finance the monetary obligations due under the
C&MA in connection with the Phase II Upgrade, including to the extent
specifically set forth on Schedule I attached to the Depositary Agreement or to
pay Network O&M Costs and after the occurrence of the Phase II RFS Date, to
finance Network O&M Costs or to finance all or part of the cost of the
engineering, construction, installation, acquisition, lease, development or
improvement of any Telecommunications Asset, in each case in accordance with and
pursuant to the Verizon Financing and (ii) secured by the C&MA. In addition, to
the extent that the Verizon Agreement or the Depositary Agreement shall be
modified or supplemented in connection with the execution and delivery of the
Verizon Debt Agreement, Bechtel shall have received a copy of such modification
or supplement and such modification or supplement shall be satisfactory in form
and substance to Bechtel. Capitalized terms used in this SECTION 5.10 and not
otherwise defined in this Agreement shall have the meanings ascribed to them in
the Depositary Agreement.

                                       26
<PAGE>

                  5.11 VENDOR AGREEMENTS. Evidence reasonably acceptable to
Bechtel that the Company shall have caused one or more of its Subsidiaries
constituting Obligors under the Citicorp Facility to (i) enter into Vendor
Agreements with Nortel Networks Inc. ("Nortel") providing in the aggregate for
the deferral of all presently outstanding Vendor Obligations due from the
Obligors to Nortel (IE. US$231 million) after giving effect to a maximum cash
payment of US$15,000,000 in connection with such deferral and (ii) enter into
Vendor Agreements with one or more other Vendors (IE. excluding Nortel but
including Bechtel) providing for the deferral of Vendor Obligations payable to
such Vendors in an aggregate amount (as to all such other Vendors) of not less
than US$230,000,000 (the terms of this Agreement shall be included in this
calculation and a summary of the other Vendor Agreements (excluding the Vendor
Agreement with Nortel) is set forth in SCHEDULE 5.11 attached hereto), each of
which Vendor Agreements with Nortel or any such other Vendor shall be in form
and substance, and shall provide for a deferral of Vendor Obligations upon
terms, satisfactory to Bechtel. In addition, with respect to any Vendors that
are entitled to the benefits of any collateral security for any of the Vendor
Obligations held by them, the Obligors, such Vendors (including Bechtel), the
Administrative Agent and the Collateral Agent (acting for the benefit of such
Vendors) shall have executed and delivered the Intercreditor and Collateral
Agency Agreement.

                  5.12 CITICORP FACILITY. Evidence reasonably acceptable to
Bechtel that each condition to the funding of the Citicorp Facility shall have
been met and each lender thereunder shall be in a position to fund all amounts
to be funded thereunder.

                  5.13 OTHER TRANSACTIONS. Evidence reasonably acceptable to
Bechtel that the Company and each of the parties thereto shall be in a position
to simultaneously consummate: (a) the Citicorp Facility, (b) the Nortel
Financing, (c) the Affiliate Financing, (d) the Verizon Financing and (e) each
Vendor Financing in each case upon terms and subject to conditions reasonably
satisfactory to Bechtel as to their form and substance.

                  5.14 FINANCIAL PROJECTIONS. Consolidated projected balance
sheets and statements of income, stockholders' equity and cash flows of the
Company and its Restricted Subsidiaries, covering the period commencing on
January 1, 2001 through June 30, 2006 (detailed by fiscal quarter through
December 31, 2004).

                  5.15 NO MATERIAL ADVERSE CHANGE. Since the date hereof, there
shall have been no Material Adverse Effect.

                  5.16 NO MATERIAL JUDGMENT OR ORDER. There shall not be on the
Closing Date any Order of a court of competent jurisdiction or any ruling of any
Governmental Authority or any condition imposed under any Requirement of Law
which would (a) prohibit or restrict (i) the issuance by the Company or MFNS or
acceptance by Bechtel of the Note or Warrant or (ii) the consummation of the
transactions contemplated by this Agreement and the other Transaction Documents,
(b) subject Bechtel to any material penalty or onerous condition under or
pursuant to any Requirement of Law if the Note or Warrant were to be acquired
hereunder or (c) restrict the operation of the

                                       27
<PAGE>

business of the Company or MFNS as conducted on the date hereof in a manner that
would have a Material Adverse Effect.

                  5.17 NO LITIGATION. No action, suit, proceeding, claim or
dispute shall have been brought or otherwise arisen at law, in equity, in
arbitration or before any Governmental Authority against the Company or MFNS
which would, if adversely determined, have a Material Adverse Effect.

                  5.18 INSURANCE. Evidence reasonably acceptable to Bechtel of
the existence of all insurance required to be maintained by the Company and its
Restricted Subsidiaries under the Note.

                  5.19 DUE DILIGENCE. Bechtel is reasonably satisfied in all
respects with the results of its due diligence investigation of the Company,
MFNS and their Subsidiaries and is reasonably satisfied with the condition
(financial or otherwise) and the viability of the Company, MFNS and their
Subsidiaries.

                  5.20 BASIC DOCUMENTS. Bechtel shall have received copies of
each of the Basic Documents and shall be reasonably satisfied that no Basic
Document shall have terms materially more favorable in the aggregate to the
lenders thereunder then the terms of the Transaction Documents in the aggregate
to Bechtel.

                  5.21 MECHANICS' AND MATERIALMANS' LIENS. Evidence that no
mechanics' or materialman's Liens have been filed against any Obligors other
than the Liens specified in SECTION 3.01(q) of the Citicorp Facility.

                  5.22 CERTAIN ADDITIONAL CONDITIONS. Evidence satisfactory to
Bechtel that, without limiting the generality of the representation and warranty
set forth in SECTION 3.27 which, pursuant to Section 5.1 must be true and
correct as a condition to Bechtel's obligation to consummate the transactions
contemplated hereby, the destruction of the World Trade Center on September 11,
2001, and the collapse of neighboring buildings and market disruptions as a
consequence thereof (and any damage that may have been caused to fiberoptic
networks of the Company and its Restricted Subsidiaries in that area) will not
result in a Material Adverse Effect;

                  5.23 OTHER. Such other approvals, opinions and documents
relating to this Agreement and the transactions contemplated hereby as Bechtel
may reasonably request.

                                   ARTICLE VI

                                OTHER AGREEMENTS

                  6.1 MODIFICATION OF OTHER RESTRUCTURING AGREEMENTS. For a
period of six (6) months after the date hereof, prior to the Company or any of
its Subsidiaries entering into an amendment, modification or supplement to any
of the agreements, arrangements or understandings executed in connection with
the Restructuring that after

                                       28
<PAGE>

giving effect to such amendment, supplement or modification, in the aggregate,
are less favorable than the rights provided to Bechtel under the Transaction
Documents, the Company shall notify Bechtel of its intention to enter into such
an amendment, modification or supplement and Bechtel shall determine, in its
sole discretion, whether it wishes to amend, modify or supplement the
Transaction Documents to incorporate the proposed amendment, modification or
supplement.

                  6.2 TERMINATION AND RELEASE.

                  (a) The Company, MFNS and Bechtel acknowledge and agree that,
upon the occurrence of the Closing, the Master Services Agreement shall be
deemed terminated, and the parties thereto shall have no further obligations
thereunder, except as specifically set forth herein. However, notwithstanding
the foregoing and Section 15.19 of the Master Services Agreement, the following
sections or articles of the Master Services Agreement shall survive the
termination of such agreement and shall remain in full force and effect:

                  i)      Article II
                  ii)     Sections 6.1, 6.2 and 6.4
                  iii)    Article VIII;
                  iv)     Article XI;
                  v)      Article XIII; and
                  vi)     Sections 15.3 and 15.4.

                  (b) Notwithstanding the termination of the Master Services
Agreement in accordance with SECTION 6.2(a) hereof, the Company shall ensure
that the completed operations coverages contained in the commercial general
liability and excess liability policies provided under the Owner Controlled
Insurance Program ("OCIP") remain in full force and effect for a period of not
less than five (5) years following completion of the Work (as such term is
defined in the Master Services Agreement). Further, all such OCIP policies
written on a claims-made basis shall contain an extended reporting period
provision of not less than one (1) year from the expiration of the policy. Still
further, the so-called "SubGuard" insurance policy provided by the Company shall
remain in place at least until the expiration of all warranty obligations of
Bechtel and all subcontractors of every tier under Article VIII of the Master
Services Agreement.

                  (c) Except as set forth in this SECTIONS 6.2 and 6.3 and
ARTICLE VII, the transactions contemplated by this Agreement and the other
Transaction Documents shall be the final settlement, discharge and satisfaction
of all amounts due and owing by the Company, MFNS and each of their respective
directors, officers, Affiliates, Subsidiaries, agents, employees and/or
designees and any of their respective predecessors, successors or assigns (the
"COMPANY PARTIES") prior to the date hereof to Bechtel and its directors,
officers, Affiliates, Subsidiaries agents, employees and/or designees and any of
their respective predecessors, successors or assigns (the "BECHTEL PARTIES")
under the Master Services Agreement or any other contract, agreement or
understanding relating thereto (except for this Agreement or any Transaction
Document). The Bechtel Parties hereby fully and unconditionally release,
discharge and forgive each of the Company Parties

                                       29
<PAGE>

from any and all past, present or future claims, causes of action, suits, debts,
dues, sums of money, accounts, bonds, bills, damages, judgments, losses,
obligations, liabilities, recoveries, demands, deficiencies, costs, expenses or
amounts ("CLAIMS") that the Bechtel Parties ever had, now have or hereafter can,
shall or may have or could or may assert against the Company Parties, whether
arising under contract, in law or in equity, in connection with the Master
Services Agreement (except for Claims arising out of the obligations contained
in, and transactions contemplated by, this Agreement or any Transaction Document
and except for Claims that survive termination of the Master Services Agreement
in accordance with SECTION 6.2(a) hereof). The Company Parties hereby fully and
unconditionally release, discharge and forgive each of the Bechtel Parties from
any and all Claims that the Company Parties ever had, now has or hereafter can,
shall or may have or could or may assert against the Bechtel Parties, whether
arising under contract, in law or in equity, in connection with the Master
Services Agreement (except for Claims arising out of the obligations contained
in, and transactions contemplated by, the Letter Agreement and except for Claims
that survive termination of the Master Services Agreement in accordance with
SECTION 6.2(a) hereof).

                  6.3 LIQUIDATED DAMAGES AMOUNT. Notwithstanding the termination
of the Master Services Agreement in accordance with SECTION 6.2(a) hereof, the
Company and Bechtel hereby agree that the amount that would currently be due and
owing to Bechtel under Section 5.8 of the Master Services Agreement is US$16.8
million (the "LIQUIDATED DAMAGES AMOUNT"), that such amount shall remain due and
owing in accordance with the terms of that agreement and that, unless further
work is granted to Bechtel pursuant to and in accordance with an agreement
entered into by the parties (which agreement, if any, shall be negotiated in
good faith), so as to reduce the Liquidated Damages Amount in accordance with
the procedures to be set forth in any such agreement, the Liquidated Damages
Amount shall be paid to Bechtel in accordance therewith on the first date such
payment would be required to be made under the Master Services Agreement.

                  6.4 WRITTEN CONSENT. (a) As promptly as practicable after the
date hereof, the Company shall (i)(x) duly call a special meeting of the holders
of the Company's Common Stock and Class B Common Stock (the "COMPANY
STOCKHOLDERS' MEETING") to be held to consider approval of the issuance of the
shares of Common Stock issuable upon conversion of the Note and upon exercise of
the Warrant, and (y) prepare and file with the SEC a proxy statement (the "PROXY
STATEMENT") relating to the Company Stockholders' Meeting and the approval of
the shares of Common Stock issuable upon conversion of the Note and upon
exercise of the Warrant, or (ii) prepare and file with the SEC an Information
Statement meeting the requirements of Schedule 14C under the Exchange Act (the
"INFORMATION STATEMENT") regarding, and containing the requisite information
describing, the Written Consent and the approval, among other things, of the
shares of Common Stock issuable upon conversion of the Note and upon exercise of
the Warrant and containing all other applicable information required under
Regulation 14C and Schedule 14C under the Exchange Act; IT BEING UNDERSTOOD AND
AGREED, that, so long as it is permissible under the rules and regulations of
NASDAQ to obtain the approval of the shares of Common Stock issuable upon
conversion of the Note and upon exercise of the Warrant by written consent and
not at a Company Stockholders' Meeting, the

                                       30
<PAGE>

Company shall be obligated to comply with the provisions of clause (ii) hereof
and the other provisions in this SECTION 6.4 relating to the Information
Statement. The Company shall use its reasonable best efforts to cause the Proxy
Statement or the Information Statement, as the case may be, to become cleared as
promptly as practicable by the SEC. The Company shall use its best efforts to
file the Proxy Statement or the Information Statement, as the case may be, no
later than October 5, 2001, and, to the extent applicable, to hold the Company
Stockholders' Meeting, or to cause the corporate action to be taken under the
Written Consent to be effective by, no later than November 15, 2001. As promptly
as practicable (but, in any event, within two (2) Business Days) after the Proxy
Statement or the Information Statement, as the case may be, is (or is deemed)
cleared by the SEC, the Company shall cause the Proxy Statement or the
Information Statement, as the case may be, to be mailed to the stockholders of
the Company. The Company shall cause the Proxy Statement or the Information
Statement, as the case may be, to comply as to form and substance in all
material respects with the applicable requirements of (i) the Exchange Act,
including the applicable provisions of Sections 14(a), 14(c) and 14(d) thereof
and the respective regulations promulgated thereunder, and (ii) applicable rules
and regulations of The Nasdaq Stock Market ("NASDAQ"). In connection with the
preparation, filing and delivery of the Proxy Statement or the Information
Statement, as the case may be, the Company shall comply in all material respects
with the applicable requirements of the Exchange Act, including the applicable
provisions of Sections 14(a), 14(c) and 14(d) thereof and Regulations 14A, 14C
and 14D thereunder.

                  (b) To the extent applicable, the Company will, through its
Board of Directors, unanimously recommend, and the Proxy Statement shall include
the unanimous and unconditional recommendation of the Board of Directors, to the
stockholders of the Company that they vote, as required by NASDAQ, in favor of
the issuance of the shares of Class A Common Stock issuable upon conversion of
the Note and upon exercise of the Warrant.

                  (c) To the extent applicable, the Company shall call and hold
the Company Stockholders' Meeting as promptly as practicable after the mailing
date of the Proxy Statement for the purpose of voting upon the issuance of the
shares of Common Stock issuable upon conversion of the Note and upon exercise of
the Warrant. To the extent applicable, the Company shall use its reasonable best
efforts (through its agents or otherwise) to solicit from its stockholders
proxies in favor of the issuance of the shares of Common Stock issuable upon
conversion of the Note and upon exercise of the Warrant.

                  (d) The Company shall take all other actions necessary to
secure the Requisite Company Vote.

                  (e) Within two (2) Business Days of obtaining the Requisite
Company Vote, the Company shall provide written notice thereof to Bechtel.

                                       31
<PAGE>

                                  ARTICLE VII

                                 INDEMNIFICATION

                  7.1 INDEMNIFICATION. Each of the Company and MFNS shall,
jointly and severally, indemnify and hold harmless Bechtel and its directors,
officers, employees, shareholders, Affiliates, Subsidiaries and agents (each, an
"INDEMNIFIED PERSON") on demand from and against any and all losses, claims,
damages, liabilities (or actions or other proceedings commenced or threatened in
respect thereof) and expenses that arise out of, result from, or in any way
relate to, this Agreement or any other Transaction Document, or in connection
with the other transactions contemplated hereby or thereby, and to reimburse
each indemnified person, upon its demand, for any legal or other expenses
incurred in connection with investigating, defending or participating in the
defense of any such loss, claim, damage, liability, action or other proceeding
(whether or not such indemnified person is a party to any action or proceeding
out of which any such expenses arise), other than any of the foregoing claimed
by any indemnified person to the extent incurred by reason of the gross
negligence or willful misconduct of such indemnified person. No indemnified
person shall be responsible or liable to either the Company, MFNS or any other
Person for any damages which may be alleged as a result of or relating to this
Agreement or any other Transaction Document (other than in connection with a
breach of this Agreement or such other Transaction Document), or in connection
with the other transactions contemplated hereby or thereby.

                  7.2 CONTRIBUTION. If the indemnification provided for in
SECTION 7.1 is unavailable to an indemnified person in respect of any losses
referred to therein, then in lieu of indemnifying such indemnified person, the
Company and MFNS shall each contribute to the amount paid or payable by such
indemnified person as a result of such losses in such proportion as is
appropriate to reflect the relative fault of the Company and/or MFNS and the
indemnified person in connection with the actions which resulted in such losses,
as well as any other relevant equitable considerations. The relative faults of
the Company, MFNS and the indemnified person shall be determined by reference
to, among other things, whether any action in question, including any untrue or
alleged untrue statement of a material fact or omission or alleged omission to
state a material fact, has been made by, or relates to information supplied by,
the Company, MFNS or the indemnified person, and the parties relative intent,
knowledge, access to information and opportunity to correct or prevent such
action. The amount paid or payable by a party as a result of the losses referred
to above shall be deemed to include, subject to the limitations set forth in
SECTIONS 7.1, any legal or other fees, disbursements or charges reasonably
incurred by such party in connection with any investigation or proceeding.

                                       32
<PAGE>

                                  ARTICLE VIII

                            TERMINATION OF AGREEMENT

                  8.1 TERMINATION. This Agreement may be terminated prior to the
Closing as follows:

                  (a) at any time on or prior to the Closing Date, by mutual
written consent of the Company, MFNS and Bechtel.

                  (b) at the election of Bechtel, by written notice to the other
parties hereto after 5:00 p.m., New York time, on or after October 1, 2001, if
the Closing shall not have occurred, unless such date is extended by the mutual
written consent of the Company, MFNS and Bechtel; PROVIDED, HOWEVER, that the
right to terminate this Agreement under this SECTION 8.1(b) shall not be
available (i) to any party whose breach of any representation, warranty,
covenant or agreement under this Agreement or any other Transaction Document has
been the cause of, or resulted in, the failure of the Closing to occur on or
before such date or (ii) if the Closing has not occurred solely because any
party hereto has not yet obtained a necessary approval from any governmental
authority.

                  (c) with respect to Bechtel, at its election, at any time if
there has been a material breach of any representation, warranty, covenant or
agreement on the part of the Company contained in this Agreement or the other
Transaction Documents, which breach has not been cured within fifteen Business
Days after notice to the Company of such breach.

                  (d) with respect to the Company or MFNS, at its election, at
any time if there has been a material breach of any representation, warranty,
covenant or agreement on the part of Bechtel contained in this Agreement, which
breach has not been cured within fifteen Business Days after notice to Bechtel
of such breach.

If this Agreement so terminates, it shall become null and void and have no
further force or effect, except as provided in SECTION 8.2.

                  8.2 SURVIVAL. If this Agreement is terminated and the
transactions contemplated hereby are not consummated as described above, this
Agreement shall become void and of no further force and effect, except for the
provisions of ARTICLE I and this SECTION 8.2; PROVIDED, HOWEVER, that (a) none
of the parties hereto shall have any liability in respect of a termination of
this Agreement pursuant to SECTION 8.1(a) or SECTION 8.1(b) and (b) nothing
shall relieve any of the parties from liability for actual damages resulting
from a termination of this Agreement pursuant to SECTION 8.1(c) or 8.1(d); and
PROVIDED FURTHER that none of the parties hereto shall have any liability for
speculative, indirect, unforeseeable or consequential damages or lost profits
resulting from any legal action relating to any termination of this Agreement.

                                       33
<PAGE>

                                   ARTICLE IX

                                  MISCELLANEOUS

                  9.1 SURVIVAL OF REPRESENTATIONS AND WARRANTIES. The
representations and warranties contained in SECTION 3.1, 3.2, 3.10, 3.11, 3.12,
3.25, 3.29, 3.35 and 3.36 shall survive until the expiration of all applicable
statutes of limitation (including extensions thereof) and all of the other
representations and warranties made herein shall survive the execution and
delivery of this Agreement until the payment in full of all obligations of MFNS
and the Company under the Note and this Agreement. All covenants and agreements
contained in this Agreement (which terms do not include representations and
warranties) shall, except as provided in such covenant or agreement, survive the
Closing and shall remain operative and in full force and effect.

                  9.2 NOTICES. All notices, demands and other communications
provided for or permitted hereunder shall be made in writing and shall be by
registered or certified first-class mail, return receipt requested, telecopier
(with a copy also sent by registered or certified first-class mail), overnight
courier service or personal delivery:

                           (a)      if to the Company or MFNS:

                                    Metromedia Fiber Network, Inc.
                                    360 Hamilton Avenue
                                    White Plains, New York  10601
                                    Attention:  Robert J. Sokota, Esq.
                                    Facsimile:  (914) 421-6793

                                    with a copy to:

                                    Paul, Weiss, Rifkind, Wharton & Garrison
                                    1285 Avenue of the Americas
                                    New York, New York  10019-6064
                                    Attention:  Douglas A. Cifu, Esq.
                                    Facsimile:  (212) 757-3990

                           (b)      if to Bechtel:

                                    c/o Bechtel Enterprises Holdings, Inc.
                                    50 California Street, Suite 2200
                                    P.O. Box 193965
                                    San Francisco, California  94119-3965
                                    Attention:  Michael C. Bailey
                                    Facsimile:  (415) 951-0850

                                       34
<PAGE>

                                    with a copy to:

                                    Shearman & Sterling
                                    599 Lexington Avenue
                                    New York, New York  10023
                                    Attention:  Douglas P. Bartner, Esq.
                                    Facsimile:  (212) 848-7179

                  All such notices, demands and other communications shall be
deemed to have been duly given when delivered by hand, if personally delivered;
in five Business Days, if sent by first-class mail; when receipt is
electronically confirmed, if sent by facsimile; and in one Business Day, if
delivered by overnight courier service.

                  9.3 SUCCESSORS AND ASSIGNS; THIRD PARTY BENEFICIARIES. This
Agreement shall inure to the benefit of and be binding upon the successors and
permitted assigns of the parties hereto. Subject to applicable securities laws
and the terms and conditions thereof, Bechtel may assign any of its rights under
this Agreement or the other Transaction Documents to any of its Affiliates. The
Company may not assign any of its rights under this Agreement without the
written consent of Bechtel. Except as provided in ARTICLE VII, no Person other
than the parties hereto and their successors and permitted assigns is intended
to be a beneficiary of this Agreement.

                  9.4 AMENDMENT AND WAIVER. (a) No failure or delay on the part
of the Company, MFNS or Bechtel in exercising any right, power or remedy
hereunder shall operate as a waiver thereof, nor shall any single or partial
exercise of any such right, power or remedy preclude any other or further
exercise thereof or the exercise of any other right, power or remedy. The
remedies provided for herein are cumulative and are not exclusive of any
remedies that may be available to the Company, MFNS or Bechtel at law, in equity
or otherwise.

                  (b) Any amendment, supplement or modification of or to any
provision of this Agreement, any waiver of any provision of this Agreement, and
any consent to any departure by the Company, MFNS or Bechtel from the terms of
any provision of this Agreement, shall be effective (i) only if it is made or
given in writing and signed by the Company, MFNS and Bechtel and (ii) only in
the specific instance and for the specific purpose for which made or given.

                  9.5 COUNTERPARTS. This Agreement may be executed in any number
of counterparts and by the parties hereto in separate counterparts, each of
which when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

                  9.6 HEADINGS. The headings in this Agreement are for
convenience of reference only and shall not limit or otherwise affect the
meaning hereof.

                  9.7 GOVERNING LAW. This Agreement and the obligations arising
hereunder shall be governed by, and construed and enforced in accordance with,
the laws

                                       35
<PAGE>

of the State of New York applicable to contracts made and performed in such
State, without regard to the principles thereof regarding conflict of laws, and
any applicable laws of the United States of America. Bechtel, the Company and
MFNS each agree to submit to personal jurisdiction and to waive any objection as
to venue in the federal or New York State courts located in the County of New
York, State of New York. Service of process on Bechtel, the Company or MFNS in
any action arising out of or relating to any of the Transaction Documents shall
be effective if mailed to such party at the address listed in SECTION 9.2
hereof.

                  9.8 WAIVER OF JURY TRIAL. THE PARTIES HERETO WAIVE ALL RIGHT
TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING TO ENFORCE OR DEFEND ANY RIGHTS
UNDER THE TRANSACTION DOCUMENTS.

                  9.9 SEVERABILITY. If any one or more of the provisions
contained herein, or the application thereof in any circumstance, is held
invalid, illegal or unenforceable in any respect for any reason, the validity,
legality and enforceability of any such provision in every other respect and of
the remaining provisions hereof shall not be in any way impaired, unless the
provisions held invalid, illegal or unenforceable shall substantially impair the
benefits of the remaining provisions hereof.

                  9.10 RULES OF CONSTRUCTION. Unless the context otherwise
requires, references to articles, sections or subsections refer to articles,
sections or subsections of this Agreement.

                  9.11 ENTIRE AGREEMENT. This Agreement, together with the
exhibits and schedules hereto (and those schedules to the Citicorp Facility
referenced herein), and the other Transaction Documents are intended by the
parties as a final expression of their agreement and intended to be a complete
and exclusive statement of the agreement and understanding of the parties hereto
in respect of the subject matter contained herein and therein. There are no
restrictions, promises, representations, warranties or undertakings, other than
those set forth or referred to herein or therein. This Agreement, together with
the exhibits and schedules hereto, and the other Transaction Documents supersede
all prior agreements and understandings between the parties with respect to such
subject matter.

                  9.12 FURTHER ASSURANCES. Each of the parties hereto shall
execute such documents and perform such further acts (including, without
limitation, obtaining any consents, exemptions, authorizations or other actions
by, or giving any notices to, or making any filings with, any Governmental
Authority or any other Person) as may be reasonably required or desirable to
carry out or to perform the provisions of this Agreement.

                  9.13 PUBLICITY. Neither Bechtel nor the Company (or any of its
Subsidiaries) shall issue any press release or make any public disclosure
regarding the transactions contemplated hereby unless such press release or
public disclosure is approved by the other party in advance. Notwithstanding the
foregoing, each of the parties hereto may, in documents required to be filed by
it with the SEC or other

                                       36
<PAGE>

regulatory bodies, make such statements with respect to the transactions
contemplated hereby as each may be advised by counsel is legally necessary or
advisable, and may make such disclosure as it is advised by its counsel is
required by law, subject, in any such case, to advance consultation with
Bechtel.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                                       37
<PAGE>

                  IN WITNESS WHEREOF, the undersigned have executed, or have
caused to be executed, this Agreement on the date first written above.

                                   METROMEDIA FIBER NETWORK, INC.

                                   By: /s/ Nick Tanzi
                                      ---------------------------------------
                                      Name:  Nick Tanzi
                                      Title: President & CEO

                                   METROMEDIA FIBER NETWORK SERVICES, INC.

                                   By: /s/ Nick Tanzi
                                      ----------------------------------------
                                      Name:  Nick Tanzi
                                      Title: President & CEO

                                   BECHTEL CORPORATION

                                   By: /s/ George E. Conniff
                                      ----------------------------------------
                                          Name:  George E. Conniff
                                          Title: President, Telecommunications
                                                 and Industrial

                                       38<Page>

                                                                  EXHIBIT 10.12

                                                                  EXECUTION COPY

      THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
      AMENDED (THE "ACT"), OR THE SECURITIES LAWS OF ANY STATE. THE SECURITIES
      MAY NOT BE TRANSFERRED EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION
      STATEMENT UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT
      TO AN APPLICABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF SUCH ACT
      AND SUCH LAWS OR PURSUANT TO A WRITTEN OPINION OF COUNSEL FOR THE COMPANY
      THAT SUCH REGISTRATION IS NOT REQUIRED.

                     METROMEDIA FIBER NETWORK SERVICES, INC.

              8.5% SENIOR SUBORDINATED CONVERTIBLE PROMISSORY NOTE
                             DUE SEPTEMBER 30, 2003

US$89,000,000.00                                                 October 1, 2001
                                                              New York, New York

            1. RESTRUCTURING AGREEMENT; OTHER NOTES. This 8.5% Senior
Subordinated Convertible Promissory Note (this "NOTE") is issued pursuant to
Section 2.1(b) of the Master Restructuring Agreement, dated as of October 1,
2001, by and among Metromedia Fiber Network, Inc., a Delaware corporation
("MFN"), Metromedia Fiber Network Services, Inc., a Delaware corporation (the
"COMPANY"), and Bechtel Corporation ("BECHTEL"), a Nevada corporation, (as the
same may be amended, supplemented or modified from time to time, the "MASTER
RESTRUCTURING AGREEMENT"). The holder of this Note is entitled to the benefits
of this Note and the Master Restructuring Agreement applicable to it and may
enforce the agreements contained herein and therein and exercise the remedies
provided for hereby and thereby or otherwise available in respect hereto and
thereto, but only to the extent permitted hereby and thereby. Capitalized terms
used herein and not otherwise defined herein have the meanings specified in the
Master Restructuring Agreement. This Note represents amounts owing to Bechtel in
connection with the Master Services Agreement, under which the Company financed
the cost of the engineering and construction of its fiber optic network and
other Telecommunications Assets.

            2. PRINCIPAL. For value received, the Company promises to pay to the
order of Bechtel Corporation or its successors or permitted assigns (the
"HOLDER") the principal amount of the sum of EIGHTY NINE MILLION DOLLARS
(US$89,000,000) in twenty-four equal installments of US$3,708,333 each on the
last day of each month commencing on October 31, 2001 or, if any such date shall
not be a Business Day, on the next succeeding Business Day to occur after such
date; PROVIDED that the final principal repayment installment on this Note shall
be repaid in full on September 30, 2003 (which

<Page>
                                                                               2
date, or such earlier date to which the maturity of this Note is accelerated,
shall be referred to as the "MATURITY DATE"), and in any event such final
principal payment shall be in an amount equal to the aggregate principal amount
of this Note outstanding on such date, with interest thereon from time to time
as provided herein. All payments of principal and interest shall be paid in U.S.
dollars by wire transfer of immediately available funds to an account designated
in writing prior to the date thereof by the Holder.

            3. INTEREST. The Company promises to pay interest on the outstanding
principal amount of this Note at the rate of 8.5% per annum. The Company shall
pay accrued interest monthly on the last day of each month or, if any such date
shall not be a Business Day, on the next succeeding Business Day to occur after
such date (each date upon which interest shall be so payable, an "INTEREST
PAYMENT DATE"), beginning on October 31, 2001. Interest on this Note shall
accrue from the date of issuance until repayment of the principal and payment of
all accrued interest in full. Interest shall be computed on the basis of a
360-day year of twelve 30-day months and shall be paid on each Interest Payment
Date. If an Event of Default shall have occurred and be continuing during any
period, the Company shall, notwithstanding anything else in this Agreement to
the contrary, pay to the Holder interest, during such period, at the applicable
rate of interest thereto plus 3% per annum on the principal of the Note, and on
any other amount whatsoever then due and payable by the Company hereunder to or
for the account of the Holder, such interest to be payable from time to time on
demand. Notwithstanding anything herein to the contrary, the interest payable by
the Company with respect to this Note shall not exceed the maximum amount
permitted by applicable law and, to the extent that any payments in excess of
the permitted amount are received by the Holder, such excess shall be considered
payments in respect of the principal amount of this Note.

            4. SECURITY. This Note is secured by the Vendor Collateral described
in the Junior Security Agreement subject to the terms of the Intercreditor and
Collateral Agency Agreement, including, without limitation, the priorities set
forth in Article IV thereof.

            5. RANKING. This Note shall be the senior secured obligation of the
Company, subordinated in priority of Collateral and right of payment to the
Senior Secured Obligations in accordance with the terms of the Intercreditor and
Collateral Agency Agreement and pari passu to all other senior obligations of
the Company.

            6. INCORPORATION BY REFERENCE. Each of the Sections in ARTICLES V
and VI (other than SECTIONS 5.04 and 5.13) of the Note and Guarantee Agreement
and each of the capitalized terms used in such Sections and defined in Article I
thereof is hereby incorporated herein by this reference, except that each
reference therein to the "AGREEMENT" or "NOTE" shall be deemed to be a reference
to this Note, each reference to a "HOLDER" shall be deemed to be a reference to
the Holder under this Note, each reference to "NOTE DOCUMENTS" shall be deemed
to be a reference to the Transaction Documents, and each reference to the
"ADMINISTRATIVE AGENT" shall be deemed to be a reference to the Holder under
this Note. Notwithstanding the foregoing, to the extent any of the

<Page>
                                                                               3

foregoing Sections of the Note and Guarantee Agreement incorporated by reference
in this Note are modified, amended, restated or supplemented in accordance with
the terms of the Note and Guarantee Agreement, then such Sections shall be
deemed so modified, amended, restated or supplemented as incorporated by
reference into this Note, without any action or consent by the Holder.

            7.    DEFAULTS AND REMEDIES.

                  (a) EVENTS OF DEFAULT. "EVENTS OF DEFAULT" are:

                      (i) default for 3 Business Days in the payment when due of
interest on the Note;

                      (ii) default in the payment when due of the principal of,
or premium, if any, on the Note;

                      (iii) the occurrence and continuation of any Indenture
Event of Default under and as defined in either of the Indentures;

                      (iv) failure by the Company to comply with any covenant,
condition or agreement contained in Section 6 (with respect to Section 5.03(a)
and Article VI of the Note and Guarantee Agreement) of this Note;

                      (v) failure by the Company to comply with any of its other
agreements (other than those specified in clauses (i), (ii) and (iv) above)
under this Note or any other Transaction Document and such default shall
continue unremedied for a period of 30 days after notice thereof from the Holder
to the Company;

                      (vi) any representation or warranty of the Company made or
deemed made in or in connection with this Note or any Transaction Document, or
any representation or warranty contained in any report, certificate, financial
statement or other instrument furnished in connection with or pursuant to this
Note or any Transaction Document, shall prove to have been false or misleading
in any material respect when so made, deemed made or furnished;

                      (vii) the Company or any Restricted Subsidiary shall (x)
fail to make any payment (whether of principal or interest and regardless of
amount) in respect of any Material Indebtedness, when and as the same shall
become due and payable (after giving effect to any grace period provided in the
underlying documentation providing for such Indebtedness) or (y) fail to observe
or perform any other term, covenant, condition or agreement contained in any
agreement or instrument evidencing or governing any Material Indebtedness if the
effect of any failure referred to in this clause (vi) is to cause or permit such
Indebtedness (without any further lapse of time or other action, other than the
mere giving of notice) to become due prior to its stated maturity, unless such
default or event of default has been waived in accordance with the terms of such
Material Indebtedness;

<Page>
                                                                               4

                      (viii) failure by the Company or any of its Restricted
Subsidiaries to pay final judgments not subject to appeal aggregating in excess
of US$5.0 million (net of applicable insurance coverage which is acknowledged in
writing by the insurer), which judgments are not paid, vacated, discharged or
stayed for a period of 30 days;

                      (ix) upon the occurrence of a Change of Control;

                      (x) an involuntary proceeding shall be commenced or an
involuntary petition shall be filed in a court of competent jurisdiction seeking
(x) relief in respect of the Company or any Restricted Subsidiary, or of a
substantial part of the property or assets of the Company or any Restricted
Subsidiary, under the Bankruptcy Code or any other Federal, state or foreign
bankruptcy, insolvency, receivership or similar law, (y) the appointment of a
receiver, trustee, custodian, sequestrator, conservator or similar official for
the Company or any Restricted Subsidiary or for a substantial part of the
property or assets of any such Obligor or (z) the winding-up or liquidation of
the Company or any Restricted Subsidiary; and such proceeding or petition shall
continue undismissed for 60 days or an order or decree approving or ordering any
of the foregoing shall be entered;

                      (xi) the Company or any Restricted Subsidiary shall (u)
voluntarily commence any proceeding or file any petition seeking relief under
the Bankruptcy Code or any other Federal, state or foreign bankruptcy,
insolvency, receivership or similar law, (v) consent to the institution of, or
fail to contest in a timely and appropriate manner, any proceeding or the filing
of any petition described in clause (ix) above, (w) apply for or consent to the
appointment of a receiver, trustee, custodian, sequestrator, conservator or
similar official for any such Obligor or for a substantial part of the property
or assets of any such Obligor, (x) file an answer admitting the material
allegations of a petition filed against it in any such proceeding, (y) make a
general assignment for the benefit of creditors or (z) take any action for the
purpose of effecting any of the foregoing;

                      (xii) the Company or any Restricted Subsidiary shall admit
in writing its inability to, or be generally unable to, pay its debts as such
debts become due;

                      (xiii) any security interest purported to be created by
any Junior Security Document with respect to Vendor Collateral of the Holder and
required thereunder to be perfected shall cease to be a valid second lien and
prior perfected security interest in the assets or properties covered thereby,
subject only to the terms of the Intercreditor and Collateral Agency Agreement,
except to the extent that any such loss of perfection or priority results from
any action or failure to take action of the Collateral Agent; or the Company
shall assert in writing that any security interest purported to be created by
any Junior Security Document and required thereunder to be perfected is not a
valid second lien and prior perfected security interest (subject only to the
terms of the Intercreditor and Collateral Agency Agreement) in the assets or
properties purported to be covered thereby; or

<Page>
                                                                               5

                      (xiv) except as set forth in Section 7(d), an event of
default shall have occurred and be continuing under and as defined in any Basic
Document unless such event of default has been waived in accordance with the
terms of such Basic Document.

            (b)   ACCELERATION. If any Event of Default occurs and is
continuing, then the Holder, by written notice to the Company, may declare the
principal of and accrued interest on this Note to be due and payable
immediately; PROVIDED, if any of the High Yield Notes immediately become due and
payable, the principal of and all accrued interest on this Note shall become due
and payable without further action or notice. Upon such declaration, such
principal and interest shall become immediately due and payable without
presentment, demand, protest or other notice of any kind, all of which the
Company hereby expressly waives.

            (c)   NOTICES. The Company shall give written notice to the Holder
of the occurrence of any Event of Default or any event that, after notice or
lapse of time or both, could become an Event of Default.

            (d)   WAIVER OF DEFAULT UNDER NOTE AND GUARANTEE AGREEMENT. The
Holder agrees to be bound by the terms of any waiver of default or event of
default or consent thereto under the Note and Guarantee Agreement granted by the
holders in accordance with the terms of the Note and Guarantee Agreement
(including the waiver of or consent to any event that constitutes an Event of
Default under Section 7(a)(iv) of this Note); PROVIDED that the Holder will not
be bound by the terms of any consent or waiver granted under the Note and
Guarantee Agreement with respect to a Default or Event of Default under Section
7(a) (i), (ii), (vii), (ix) or (xiv) of this Note. The Company shall deliver a
copy of any such waiver to the Holder within 5 Business Days of the effective
date thereof.

            8.    REDEMPTION AT THE OPTION OF THE COMPANY.

                  (a) REDEMPTION. The Company shall have the right, at any time
and from time to time at its sole option and election, to prepay or redeem (the
"OPTIONAL REDEMPTION") this Note in principal amounts no less than US$1,000,000
(or such lesser amount as may be outstanding under this Note) on not less than
thirty (30) days' notice prior to redemption or repayment, which such Optional
Redemption shall occur on a Business Day (any such date an "OPTIONAL REDEMPTION
DATE") at a price (the "OPTIONAL REDEMPTION PRICE") equal to (i) the principal
amount of this Note being repaid plus (ii) an amount equal to all accrued and
unpaid interest under this Note, whether or not currently payable, to the
Optional Redemption Date, in cash or other immediately available funds, without
penalty or premium. The Company shall only have the right to prepay or redeem
this Note if a pro rata portion of the principal amount outstanding under each
of the Convertible Notes is prepaid or redeemed simultaneously by the Company.
The Holder's right to convert this Note under Section 10 shall remain in effect
up to, but not including, the Optional Redemption Date.

<Page>
                                                                               6

                  (b) NOTICE. Notice of the Optional Redemption (the "OPTIONAL
REDEMPTION NOTICE") shall be sent by the Company to the Holder at its address as
provided for in SECTION 19 of this Note, at least thirty (30) days prior to
redemption. In order to facilitate the redemption of this Note, the board of
directors of the Company may fix a record date for the determination of this
Note to be redeemed.

                  (c) PAYMENT OR DEPOSIT OF FUNDS. On the Optional Redemption
Date, the Company shall pay to the Holder, and at any time after the Optional
Redemption Notice shall have been sent and before the Optional Redemption Date,
the Company may deposit for the benefit of the Holder, with a bank or trust
company having a capital and surplus of at least one hundred million dollars
(US$100,000,000), the funds necessary for the Optional Redemption.

                  (d) TERMINATION OF RIGHTS. The Optional Redemption Notice
having been given as aforesaid, upon payment or the deposit of funds pursuant to
SECTION 8(C) in respect of this Note to be redeemed or repaid pursuant to
SECTION 8(A), notwithstanding that this Note shall not have been surrendered for
cancellation, from and after the Optional Redemption Date (i) the prepaid or
redeemed portion of this Note shall no longer be deemed outstanding, (ii) the
rights to receive interest upon the prepaid or redeemed portion of this Note
shall cease to accrue and (iii) all rights of the Holder, in respect of the
prepaid or redeemed portion of this Note, shall cease and terminate (including,
without limitation, the rights of conversion provided for in this Note),
excepting only the right to receive the Optional Redemption Price therefor and
subject to the next sentence. In the case this Note is prepaid or redeemed in
part only, upon such prepayment or redemption, the Company shall execute and
deliver to the Holder a new Note of authorized denominations equal in aggregate
principal amount to the unpaid or unredeemed portion of this Note but otherwise
on terms identical to this Note.

            9.    NO VOTING RIGHTS. The Holder of this Note shall not be
entitled or permitted to vote on any matter required or permitted to be voted
upon by the stockholders of the Company.

            10.   CONVERSION.

                  (a) OPTIONAL CONVERSION. The Holder shall have the right, at
its option, at any time and from time to time, to convert, subject to the terms
and provisions of this SECTION 10, all or part of the principal amount of such
Holder's Note into such number of fully paid and nonassessable shares of Common
Stock as is equal to the quotient of (i) the outstanding principal amount of the
Note to be converted PLUS any accrued and unpaid interest payable on the
aggregate principal amount to be converted (the "CONVERSION AMOUNT") divided by
(ii) the conversion price of US$0.53875, subject to adjustment as provided in
SECTION 10(E) (such price, the "CONVERSION PRICE"). Such conversion right shall
be exercised by the surrender of the Note to the Company at any time during
usual business hours at its principal place of business to be maintained by it
(or such other office or agency of the Company as the Company may designate by
notice in writing to the Holder), accompanied by written notice that the Holder
elects to convert any or all of the principal amount of the Note, specifying the
aggregate principal amount

<Page>
                                                                               7

of the Note the Holder elects to convert into shares of Common Stock (which
amount shall be in multiples of US$1,000,000 (or such lesser amount if the
aggregate principal amount then outstanding is less than US$1,000,000, in which
case the holder must elect to convert the entire amount then outstanding,
including accrued but unpaid interest thereon), and specifying the name or names
(with address) in which a certificate or certificates for shares of Common Stock
are to be issued and (if so required by the Company) by a written instrument or
instruments of transfer in form reasonably satisfactory to the Company duly
executed by the Holder or its duly authorized legal representative and transfer
tax stamps or funds therefor, only if required pursuant to SECTION 10(K). Upon
being surrendered for conversion, this Note shall be delivered to the Company
for cancellation and canceled by it, subject to the Company's obligation to
reissue such Note in accordance with the terms hereof upon conversion by the
Holder of a portion of the then outstanding principal amount. As promptly as
practicable after the surrender of this Note, MFN shall (subject to compliance
with the applicable provisions of federal and state securities laws) deliver to
the Holder a certificate or certificates representing the number of fully paid
and nonassessable shares of Common Stock into which the converted portion of
this Note is entitled to be converted. At the time of the surrender of this
Note, the Person in whose name any certificate(s) for shares of Common Stock
shall be issuable upon such conversion shall be deemed to be the holder of
record of such shares of Common Stock on such date, notwithstanding that the
share register of MFN shall then be closed or that the certificates representing
such Common Stock shall not then be actually delivered to such Person. In the
case this Note is converted in part only, upon such conversion, the Company
shall execute and deliver to the Holder a new Note of authorized denominations
equal in aggregate principal amount to the unconverted portion of this Note but
otherwise on terms identical to this Note. Notwithstanding anything to the
contrary in this Note, upon the occurrence and/or continuation of any Event of
Default, the Holder may exercise his or its conversion rights under this SECTION
10 at any time until this Note is paid in full.

                  (b) PURCHASES AND REDEMPTIONS. If at any time MFN shall
propose to purchase or redeem any shares of its Common Stock for cash, evidence
of indebtedness or other property of any nature whatsoever, MFN shall deliver to
each Holder of a Note, a notice of such proposed purchase or redemption, and
each such Holder shall, at its option, have the right to require MFN to at the
same time purchase or redeem such Holders' Note(s) (whether or not such Holders
convert such Note(s)), pro-rata based on the number of shares of such other
Common Stock to be so purchased or redeemed, on the same terms and conditions as
the proposed purchase or redemption of such other Common Stock and for the same
consideration per share of Note Stock, as the case may be, as is paid to the
holders of such other Common Stock for each share of Common Stock so redeemed or
purchased.

                  (c) FRACTIONAL SHARES. No fractional shares of Common Stock
shall be issued upon conversion of this Note. All shares of Common Stock
(including fractions thereof) issuable upon conversion of more than one Note by
the Holder thereof shall be aggregated for purposes of determining whether the
conversion would result in the issuance of any fractional share. If, after the
aforementioned aggregation, the conversion would result in the issuance of any
fractional share, the Company shall, in lieu

<Page>
                                                                               8

of MFN issuing any fractional share, pay cash equal to the product of such
fraction multiplied by the Market Price of one share of Common Stock on the date
of conversion of the Notes.

                  (d) TERMINATION OF RIGHTS. On the date of such optional
conversion pursuant to SECTION 10(A) above, all rights with respect to the
converted portion of this Note shall terminate, except for the rights of the
Holder thereof to (i) receive (or have one of its affiliates receive)
certificates for the number of shares of Common Stock into which the converted
portion of this Note have been converted, (ii) the payment of interest, if any,
pursuant to SECTION 3 above and (iii) exercise the rights to which they are
entitled as holders of Common Stock.

                  (e) ANTIDILUTION ADJUSTMENTS. The Conversion Price, and the
number and type of securities to be received upon conversion of this Note, shall
be subject to adjustment as follows:

                      (i) DIVIDEND, SUBDIVISION, COMBINATION OR RECLASSIFICATION
OF THE COMMON STOCK. In the event that MFN shall at any time or from time to
time, prior to conversion of this Note (w) pay a dividend or make a distribution
(other than a dividend or distribution in which the Holder fully participates on
account of each share of Common Stock that is then issuable hereunder) on the
outstanding shares of Common Stock payable in Capital Stock, (x) subdivide the
outstanding shares of Common Stock into a larger number of shares, (y) combine
the outstanding shares of Common Stock into a smaller number of shares or (z)
issue any shares of its Capital Stock in a reclassification of the Common Stock,
then, and in each such case, the Conversion Price in effect immediately prior to
such event shall be adjusted (and any other appropriate actions shall be taken
by MFN) so that the Holder of this Note thereafter surrendered for conversion
shall be entitled to receive the number of shares of Common Stock or other
securities of MFN that such Holder would have owned or would have been entitled
to receive upon or by reason of any of the events described above, had this Note
been converted immediately prior to the occurrence of such event. An adjustment
made pursuant to this SECTION 10(e)(i) shall become effective retroactively (x)
in the case of any such dividend or distribution, to a date immediately
following the close of business on the record date for the determination of
holders of Common Stock entitled to receive such dividend or distribution or (y)
in the case of any such subdivision, combination or reclassification, to the
close of business on the day upon which such corporate action becomes effective.

                      (ii) ISSUANCE OF COMMON STOCK OR COMMON STOCK EQUIVALENT
BELOW CONVERSION PRICE.

                           (A) If MFN shall at any time or from time to time
      prior to conversion of this Note, issue or sell any shares of Common Stock
      or Common Stock Equivalents at a price per share of Common Stock (the "NEW
      ISSUE PRICE") that is less than the Conversion Price then in effect as of
      the record date or Issue Date (as defined below) or the Market Price of
      the Common Stock on the Issue Date (the "CLOSING PRICE"), as the case may
      be (the "RELEVANT DATE")

<Page>
                                                                               9

      (treating the price per share of Common Stock, in the case of the issuance
      of any Common Stock Equivalent, as equal to (x) the sum of the price for
      such Common Stock Equivalent plus any additional consideration payable
      (without regard to any anti-dilution adjustments) upon the conversion,
      exchange or exercise of such Common Stock Equivalent divided by (y) the
      number of shares of Common Stock initially underlying such Common Stock
      Equivalent), other than (A) issuances or sales for which an adjustment is
      made pursuant to another clause of this SECTION 10(e) and (B) issuances in
      connection with an Excluded Transaction, THEN, and in each such case, the
      Conversion Price then in effect shall be adjusted by MULTIPLYING the
      Conversion Price in effect on the day immediately prior to the Relevant
      Date by a fraction (I) the numerator of which shall be the sum of the
      number of shares of Common Stock outstanding on the Relevant Date plus the
      number of shares of Common Stock which the aggregate consideration
      received by MFN for the total number of such additional shares of Common
      Stock so issued would purchase at the Conversion Price or the Closing
      Price, whichever is higher, on the Relevant Date (or, in the case of
      Common Stock Equivalents, the number of shares of Common Stock which the
      aggregate consideration received by MFN upon the issuance of such Common
      Stock Equivalents and receivable by the Corporation upon the conversion,
      exchange or exercise of such Common Stock Equivalents would purchase at
      the Conversion Price or the Closing Price, whichever is higher, on the
      Relevant Date) and (II) the denominator of which shall be the sum of the
      number of shares of Common Stock outstanding on the Relevant Date PLUS the
      number of additional shares of Common Stock issued or to be issued (or, in
      the case of Common Stock Equivalents, the maximum number of shares of
      Common Stock into which such Common Stock Equivalents initially may
      convert, exchange or be exercised).

                           (B) Such adjustment shall be made whenever such
      shares of Common Stock or Common Stock Equivalents are issued, and shall
      become effective retroactively (x) in the case of an issuance to the
      stockholders of MFN to a date immediately following the close of business
      on the record date for the determination of stockholders entitled to
      receive such shares of Common Stock or Common Stock Equivalents and (y) in
      all other cases, on the date (the "ISSUE DATE") of such issuance;
      PROVIDED, HOWEVER, that the determination as to whether an adjustment is
      required to be made pursuant to this SECTION 10(e)(ii) shall only be made
      upon the issuance of such shares of Common Stock or Common Stock
      Equivalents, and not upon the issuance of any security into which the
      Common Stock Equivalents convert, exchange or may be exercised.

                           (C) In case at any time any shares of Common Stock or
      Common Stock Equivalents or any rights or options to purchase any shares
      of Common Stock or Common Stock Equivalents shall be issued or sold for
      cash, the consideration received therefor shall be deemed to be the amount
      received by MFN therefor, without deduction therefrom of any expenses
      incurred or any underwriting commissions or concessions or discounts paid
      or allowed by MFN in connection therewith. In case any shares of Common
      Stock or Common

<Page>
                                                                              10

      Stock Equivalents or any rights or options to purchase any Common Stock or
      Common Stock Equivalents shall be issued or sold for a consideration other
      than cash, the amount of the consideration other than cash received by MFN
      shall be deemed to be the fair market value of such consideration, without
      deduction therefrom of any expenses incurred or any underwriting
      commissions or concessions or discounts paid or allowed by MFN in
      connection therewith, as determined in good faith by the Board of
      Directors.

                           (D) If any Common Stock Equivalents (or any portions
      thereof) which shall have given rise to an adjustment pursuant to this
      SECTION 10(e)(ii) shall have expired or terminated without the exercise
      thereof and/or if by reason of the terms of such Common Stock Equivalents
      there shall have been an increase or increases, with the passage of time
      or otherwise, in the price payable upon the exercise or conversion
      thereof, then the Conversion Price hereunder shall be readjusted (but to
      no greater extent than originally adjusted) in order to (x) eliminate from
      the computation any additional shares of Common Stock corresponding to
      such Common Stock Equivalents as shall have expired or terminated, (y)
      treat the additional shares of Common Stock, if any, actually issued or
      issuable pursuant to the previous exercise of such Common Stock
      Equivalents as having been issued for the consideration actually received
      and receivable therefor and (z) treat any of such Common Stock Equivalents
      which remain outstanding as being subject to exercise or conversion on the
      basis of such exercise or conversion price as shall be in effect at the
      time.

                      (iii) OTHER CHANGES. In case MFN at any time or from time
to time, prior to the conversion of this Note, shall take any action affecting
its Common Stock similar to or having an effect similar to any of the actions
described in any of SECTIONS 10(e)(i), 10(e)(ii) or 10(h) (but not including any
action described in any such Section), the Board of Directors shall in good
faith determine whether it would be equitable in the circumstances to adjust the
Conversion Price as a result of such action. If it is determined by the Board of
Directors that such an adjustment to the Conversion Price would be equitable,
THEN, and in each such case, the Conversion Price shall be adjusted in such
manner and at such time as the Board of Directors in good faith determines would
be equitable in the circumstances (such determination to be evidenced in a
resolution, a certified copy of which shall be mailed to the Holder).

                  (f) ABANDONMENT. If MFN shall take a record of the holders of
its Common Stock for the purpose of entitling them to receive a dividend or
other distribution, and shall thereafter and before the distribution to
stockholders thereof legally abandon its plan to pay or deliver such dividend or
distribution, then no adjustment in the Conversion Price shall be required by
reason of the taking of such record.

                  (g) CERTIFICATE AS TO ADJUSTMENTS. Upon any increase or
decrease in the Conversion Price, MFN shall within a reasonable period (not to
exceed ten (10) days) following any of the foregoing transactions deliver to the
Holder a certificate, signed by (i) the Chief Executive Officer of MFN and (ii)
the Chief Financial Officer of MFN, setting forth in reasonable detail the event
requiring the adjustment and

<Page>
                                                                              11

the method by which such adjustment was calculated and specifying the increased
or decreased Conversion Price then in effect following such adjustment.

                  (h) MERGER, CONSOLIDATION OR DISPOSITION OF ASSETS. If MFN
shall (i) merge or consolidate with another Person, (ii) reorganize or
reclassify or otherwise change its outstanding shares of Common Stock (other
than a change in par value, or from par value to no par value, or from no par
value to par value) or (iii) sell, transfer or otherwise dispose of all or
substantially all of its assets to another Person (each, a "TRANSACTION") and
pursuant to the terms of such Transaction, cash, shares of common stock or other
securities of the successor or acquiring Person, or property of any nature is to
be received by or distributed to the holders of Common Stock of MFN, then each
Holder of Note(s) shall, at such Holder's election, have the right to receive
(whether or not such Holder converts such notes) the amount of cash or other
consideration it would have been entitled to receive if such Holder had
converted such Notes immediately prior to the occurrence of such Transaction,
and shall thereupon be deemed to have converted such Notes. In case of any such
Transaction in which the foregoing election is not made, the successor or
acquiring Person (and any affiliate thereof issuing securities) shall expressly
assume the due and punctual observance and performance of each and every
covenant and condition to be performed and observed by, and all of the
obligations and liabilities of, MFN hereunder, subject to such modifications as
may be deemed appropriate (as determined by resolution of the Board) in order to
provide for adjustments which shall be as nearly equivalent as practicable to
the adjustments provided for in this SECTION 10. The foregoing provisions shall
similarly apply to successive Transactions.

                  (i) NOTICES. If MFN shall propose (i) to pay any dividend to
the holders of its Common Stock or to make any other distribution to the holders
of its Common Stock; (ii) to offer to the holders of its Common Stock rights to
subscribe for or to purchase any additional shares of Common Stock (or options
or rights with respect thereto); (iii) to effect any reclassification of its
Common Stock; (iv) to otherwise issue any Common Stock Equivalents; (v) to
effect any capital reorganization; (vi) to effect any consolidation, merger or
sale, transfer or other disposition of all or substantially all of its assets;
or (vii) to effect the liquidation, dissolution or winding up of MFN, then, in
each such case, MFN shall give to each Holder of Notes a notice of such proposed
action, which shall specify the date on which a record is to be taken for the
purposes of such dividend, distribution or rights offer, or the date on which
such reclassification, issuance, reorganization, consolidation, merger, sale,
transfer, disposition, liquidation, dissolution or winding up is to take place
and the date of participation therein by the holders of Common Stock, if any
such date is to be fixed, and shall also set forth such facts with respect
thereto as shall be reasonably necessary to indicate the effect of such action
on the Common Stock, and the number of shares of Common Stock into which the
Notes will be convertible after giving effect to any adjustment which will be
required as a result of such action. Such notice shall be so given in the case
of any action covered by clause (i) or (ii) above at least 20 days prior to the
record date for determining holders of the Common Stock for purposes of such
action, and in the case of any other such action, at least 20 days prior to the
date of the taking of such proposed action or the date of participation therein
by the holders of Common Stock, whichever shall be the earlier.

<Page>
                                                                              12

                  (j) RESERVATION OF COMMON STOCK. The Company shall at all
times reserve and keep available for issuance upon the conversion of this Note,
such number of its authorized but unissued shares of Common Stock as will from
time to time be sufficient to permit the conversion of the entire principal
amount of this Note, and shall take all action to increase the authorized number
of shares of Common Stock if at any time there shall be insufficient authorized
but unissued shares of Common Stock to permit such reservation or to permit the
conversion of the entire principal amount of this Note.

                  (k) NO CONVERSION TAX OR CHARGE. The issuance or delivery of
certificates for Common Stock upon the conversion of this Note shall be made
without charge to the converting Holder for such certificates or for any tax in
respect of the issuance or delivery of such certificates or the securities
represented thereby, and such certificates shall be issued or delivered in the
respective names of, or (subject to compliance with the applicable provisions of
federal and state securities laws) in such names as may be directed by, the
Holder of the portion of this Note converted; PROVIDED, HOWEVER, that MFN shall
not be required to pay any tax which may be payable in respect of any transfer
involved in the issuance and delivery of any such certificate in a name other
than that of the Holder, and MFN shall not be required to issue or deliver such
certificate unless or until the Person or Persons requesting the issuance or
delivery thereof shall have paid to MFN the amount of such tax or shall have
established to the reasonable satisfaction of MFN that such tax has been paid or
is not required to be paid by it.

                  (l) CONVERSION LIMITATION. Notwithstanding any of the
foregoing, in no event shall the Holder of this Note be permitted to convert
this Note prior to the Stockholder Approval Effective Date. For the purposes of
this Note, "STOCKHOLDER APPROVAL EFFECTIVE DATE" means the earlier to occur of
(i) the approval and ratification of the issuance of shares of Common Stock
issuable upon the conversion of this Note and upon exercise of the Warrant by a
majority of holders of Common Stock and Class B Common Stock, voting as a single
class, that are present in person or by proxy at a duly called meeting of
Company's stockholders, or (ii) the twentieth (20th) day following the delivery
by the Company of an effective Information Statement meeting the requirements of
Schedule 14C promulgated under the Exchange Act that contains the requisite
information describing the Written Consent; it being understood and agreed,
that, so long as it is permissible under the rules and regulations of NASDAQ to
obtain the approval of the shares of Common Stock issuable upon conversion of
the Note and upon exercise of the Warrant by written consent and not at a
Company Stockholders' Meeting, the Company shall be obligated to pursue the
delivery of the Information Statement described in clause (ii) above.

            11.   CERTAIN REMEDIES. Any registered Holder of this Note shall be
entitled to an injunction or injunctions to prevent breaches of the provisions
of this Note and to enforce specifically the terms and provisions of this Note
in any court of the United States or any state thereof having jurisdiction, this
being in addition to any other remedy to which such Holder may be entitled at
law or in equity.

<Page>
                                                                              13

            12.   FULL RECOURSE. The Company hereby agrees and covenants that
the Holder shall have full recourse against the Company for the payment of the
entire principal amount of this Note and all accrued interest thereon.

            13.   REMEDIES CUMULATIVE. No remedy herein conferred upon the
Holder is intended to be exclusive of any other remedy hereunder or any other
document referred to herein, and each and every such remedy shall be cumulative
and shall be in addition to every other remedy given hereunder or now or
hereafter existing at law or in equity or by statute or otherwise.

            14.   REMEDIES NOT WAIVED. No course of dealing between MFN, the
Company and the Holder or any delay on the part of the Holder in exercising any
rights hereunder shall operate as a waiver of any right.

            15.   WAIVER OF PROTEST, PRESENTMENT, ETC. The Company hereby waives
protest, presentment, notice of dishonor and notice of acceleration of maturity
and agrees to continue to remain bound for the payment of principal, interest
and all other sums due under this Note, notwithstanding any change or changes by
way of release, surrender, exchange, modification or substitution of any
security for this Note or by way of any extension or extensions of time for the
payment of principal and interest.

            16.   CURRENCY; BUSINESS DAY. All payments of interest and principal
under this Note shall be made in lawful money of the United States of America.
If any payment shall be required by the terms hereof to be made on a day that is
not a Business Day, such payment shall be made on the immediately succeeding
Business Day.

            17.   TRANSFER. The Holder acknowledges that this Note has not been
registered under the Securities Act, or the securities laws of any state, and
may be transferred only pursuant to an effective registration statement under
the Securities Act or pursuant to an applicable exemption from the registration
requirements of the Securities Act.

            18.   DEFINITIONS. As used in this Note, the following terms shall
have the following meanings (with terms defined in the singular having
comparable meanings when used in the plural and vice versa), unless the context
otherwise requires:

            "BANKRUPTCY LAW" has the meaning ascribed to that term in each of
the Indentures.

            "BASIC DOCUMENTS" has the meaning ascribed to that term in the Note
and Guarantee Agreement (including the Nortel Agreement).

            "CAPITAL STOCK" means, with respect to any Person, any and all
shares, interests, participations, rights in, or other equivalents (however
designated and whether voting or non-voting) of, such Person's capital stock and
any and all rights, warrants or options exchangeable for or convertible into
such capital stock (but excluding any debt security whether or not it is
exchangeable for or convertible into such capital stock).

<Page>
                                                                              14

            "CHANGE OF CONTROL" shall have the meaning ascribed to that term in
the Note and Guarantee Agreement.

            "CLASS B COMMON STOCK" means the shares of class B common stock, par
value US$0.01 per share, of MFN.

            "COMMON STOCK" means the shares of class A common stock, par value
US$0.01 per share, of MFN.

            "COMMON STOCK EQUIVALENT" shall mean any security or obligation
which is by its terms convertible, exchangeable or exerciseable into shares of
Common Stock of another Common Stock Equivalent, and any option, warrant or
other subscription or purchase right with respect to Common Stock.

            "COMPANY" shall have the meaning ascribed to in SECTION 1 of this
Note.

            "COMPANY STOCKHOLDERS' MEETING" has the meaning set forth in the
Master Restructuring Agreement.

            "CONVERSION AMOUNT" shall have the meaning ascribed to in SECTION
8(a) of this Note.

            "CONVERSION PRICE" shall have the meaning ascribed to it in SECTION
8(a) of this Note.

            "EVENT OF DEFAULT" shall have the meaning ascribed to it in SECTION
7 of this Note.

            "EXCLUDED TRANSACTION" means (a) any issuance of Common Stock
Equivalents or Common Stock issuable or issued upon the exercise, conversion or
exchange thereof (so long as the exercise price for such Common Stock Equivalent
is greater than or equal to the greater of (i) the Conversion Price then in
effect and (ii) the Market Price of the Common Stock issued at the time such
Common Stock Equivalent was awarded) or (b) any issuance of Common Stock upon
the exercise of any warrants, or conversion of any Common Stock Equivalents,
issued or outstanding on the date of this Note.

            "HIGH YIELD NOTES" means collectively, (i) the 10% Series A Senior
Notes due 2008 issued under the 1998 Indenture, (ii) the 10% Series B Senior
Notes due 2008 issued under the 1998 Indenture, (iii) the 10% Senior Notes due
2009 (euro) issued under the 1999 Indenture and (iv) the 10% Senior Notes due
2009 (dollar) issued under the 1999 Indenture.

            "HOLDER" shall have the meaning ascribed to it in SECTION 2 of this
Note.

            "INDEBTEDNESS" shall have the meaning ascribed to that term in the
Note and Guarantee Agreement.

<Page>
                                                                              15

            "INFORMATION STATEMENT" has the meaning set forth in the Master
Restructuring Agreement.

            "INTEREST PAYMENT DATE" shall have the meaning ascribed to it in
SECTION 3 of this Note.

            "ISSUE DATE" shall have the meaning ascribed to it in SECTION
10(e)(ii)(B) of this Note.

            "JUNIOR SECURITY DOCUMENTS" shall have the meaning ascribed to it in
the Intercreditor and Collateral Agency Agreement.

            "MATERIAL INDEBTEDNESS" shall have the meaning ascribed to it in the
Note and Guarantee Agreement (including all obligations under the Note Documents
as defined therein).

            "MARKET PRICE" shall mean, as of the date of determination: (a) the
closing price per share of Common Stock on such date published in The Wall
Street Journal or, if no such closing price on such date is published in The
Wall Street Journal, the average of the closing bid and asked prices on such
date, as officially reported on the principal national securities exchange
(including, without limitation, NASDAQ) on which the Common Stock is then listed
or admitted to trading; or (b) if the Common Stock is not then listed or
admitted to trading on any national securities exchange, but is designated as a
national market system security by the National Association of Securities
Dealers, Inc., the last trading price of the Common Stock on such date; or (c)
if there shall have been no trading on such date or if the Common Stock is not
so designated, the average of the reported closing bid and asked prices of the
Common Stock on such date as shown by the National Market System of the National
Association of Securities Dealers, Inc. Automated Quotations System and reported
by any member firm of the New York Stock Exchange selected by the Company; or
(d) if none of (a), (b) or (c) is applicable, a market price per share
determined in good faith by the Board of Directors.

            "MASTERING RESTRUCTURING AGREEMENT" shall have the meaning ascribed
to it in SECTION 1 of this Note.

            "MATURITY DATE" shall have the meaning ascribed to it in SECTION 2
of this Note.

            "MFN" shall have the meaning ascribed to it in SECTION 1 of this
Note.

            "NEW ISSUE PRICE" shall have the meaning ascribed to it in SECTION
10(e)(ii)(A) of this Note.

            "NASDAQ" has the meaning set forth in the Master Restructuring
Agreement.

            "NOTE" shall have the meaning ascribed to it in SECTION 1 of this
Note.

<Page>
                                                                              16

            "NOTE STOCK" means all shares of Common Stock issuable from time to
time upon conversion of the Note (subject to adjustment in accordance with the
terms hereof).

            "NOTE AND GUARANTEE AGREEMENT" has the same meaning as "Citicorp
Facility", as such term is defined in the Master Restructuring Agreement.

            "OBLIGORS" shall have the meaning ascribed to it in the Note and
Guarantee Agreement.

            "OPTIONAL REDEMPTION" shall have the meaning ascribed to it in
SECTION 8(a) of this Note.

            "OPTIONAL REDEMPTION DATE" shall have the meaning ascribed to it in
SECTION 8(a) of this Note.

            "OPTIONAL REDEMPTION NOTE" shall have the meaning ascribed to it in
SECTION 8(b) of this Note.

            "OPTIONAL REDEMPTION PRICE" shall have the meaning ascribed to it in
SECTION 8(a) of this Note.

            "REFINANCING AGREEMENTS" means the Citicorp Facility, the Nortel
Financing, the Master Restructuring Agreement, the Vendor Financings, the
Verizon Financing and the 6.15% Convertible Notes Restructuring.

            "RELEVANT DATE" shall have the meaning ascribed to it in SECTION
10(e)(ii)(A) hereof.

            "RESTRICTED SUBSIDIARY" shall have the meaning ascribed to that term
in the Note and Guarantee Agreement.

            "SENIOR SECURED OBLIGATIONS" shall have the meaning ascribed to that
term in the Intercreditor and Collateral Agency Agreement.

            "6.15% CONVERTIBLE NOTE RESTRUCTURING" means the restructuring of
certain terms of the 6.15% Convertible Subordinated Notes due 2010 of the
Company.

            "STOCKHOLDER APPROVAL EFFECTIVE DATE" shall have the meaning
ascribed to that term in Section 10(l) of this Note.

            "TELECOMMUNICATIONS ASSETS" shall have the meaning ascribed to that
term in the Note and Guarantee Agreement.

            "TRANSACTION" shall have the meaning ascribed to it in SECTION
10(h) of this Note.

<Page>
                                                                              17

            "WRITTEN CONSENT" has the meaning set forth in the Master
Restructuring Agreement.

            19. NOTICES. All notices, demands or other communications provided
for or permitted hereunder shall be made in writing and shall be by registered
or certified first class mail, return receipt requested, telecopier, courier
service, overnight mail or personal delivery:

                  (i)   if to MFN or the Company:

                        Metromedia Fiber Network, Inc.
                        360 Hamilton Avenue
                        White Plains, New York  10601
                        Telecopy:   (914) 421-6793
                        Attention:  Robert J. Sokota, Esq.

                        with a copy to:

                        Paul, Weiss, Rifkind, Wharton & Garrison
                        1285 Avenue of the Americas
                        New York, New York 10019-6064
                        Telecopy:   (212) 757-3990
                        Attention:  Douglas A. Cifu, Esq.

                  (ii)  if to the Holder:

                        c/o Bechtel Enterprises Holdings, Inc.
                        50 California Street, Suite 2200
                        P.O. Box 193965
                        San Francisco, California  94119-3965
                        Attention:  Michael C. Bailey
                        Facsimile: (415) 951-0850

                        with a copy to:

                        Shearman & Sterling
                        599 Lexington Avenue
                        New York, New York 10022
                        Telecopy:   (212) 848-7179
                        Attention:  Douglas P. Bartner, Esq.

<Page>
                                                                              18

Any party may by notice given in accordance with this Section 19 designate
another address or Person for receipt of notices hereunder. All such notices,
demands and other communications shall be deemed to have been duly given when
delivered by hand, if personally delivered; when delivered by courier or
overnight mail, if delivered by commercial courier service or overnight mail;
and when receipt is mechanically acknowledged, if telecopied.

            20. AMENDMENT. Any amendment, supplement or modification of or to
any provision of this Note, any waiver of any provision of this Note, and any
consent to any departure by the Company or the Holder from the terms of any
provision of this Note, shall be effective (i) only if it is made or given in
writing and signed by MFN, the Company and the Holder, and (ii) only in the
specific instance and for the specific purpose for which made or given. Except
where notice is specifically required by this Note, no notice to or demand on
MFN or the Company in any case shall entitle the Company to any other or further
notice or demand in similar or other circumstances.

            21. CONSENT OF MFN. MFN is a party to this Note solely for the
purpose of acknowledging and consenting to the provisions of SECTION 10 pursuant
to which all or part of this Note may be converted to shares of its Common Stock
and MFN hereby agrees to be bound by each of the provisions of this Note
relating to the conversion thereof into Common Stock.

            22. GOVERNING LAW. THIS NOTE SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO THE
PRINCIPLES OF CONFLICTS OF LAW THEREOF.

            23. SUCCESSORS AND ASSIGNS. This Note shall inure to the benefit of
and be binding upon the successors and permitted assigns of the parties hereto.
This Note may be assigned in whole or part, in one or more transactions, by
Bechtel, its successors and/or assigns.

            24. NO ASSIGNMENT. Neither this Note nor the rights, duties and
obligations of the Company of MFN hereto may be assigned by the Company or MFN
at any time, by operation of law or otherwise.

            25. HEADINGS. The headings in this Note are inserted for convenience
of reference only and shall not limit or otherwise affect the meaning hereof and
do not constitute part of this Note.

                         [SIGNATURES ON FOLLOWING PAGE]

<Page>
                                                                              19

            IN WITNESS WHEREOF, the Company has caused this Note to be duly
executed by its duly authorized officer as of the day and year first above
written.

                                    METROMEDIA FIBER NETWORK
                                    SERVICES, INC.

                                    By: /s/ Nick Tanzi
                                       ---------------------------------
                                       Name: Nick Tanzi
                                       Title: President & CEO

Acknowledged and Agreed as to
SECTIONS 10, 21 and 24 of this Note:

METROMEDIA FIBER NETWORK, INC.

By: /s/ Nick Tanzi
   ---------------------------------
   Name: Nick Tanzi
   Title: President & CEO

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