<PAGE>
                                                                     Exhibit 4.2

          Without limiting the obligation of the Credit Parties (as hereinafter
defined) under Section 5.04 of this Agreement to pay any such tax that may be
imposed, please be advised that taking the original of this Agreement or any
certified copy thereof into the Republic of Austria may cause Austrian stamp
duty to be assessed by the Austrian tax authorities.

                            GLOBAL SECURITY AGREEMENT

          GLOBAL SECURITY AGREEMENT dated as of December 9, 2003, between GLOBAL
CROSSING NORTH AMERICAN HOLDINGS, INC., a corporation duly organized and validly
existing under the laws of the State of Delaware (the "Issuer"), GLOBAL CROSSING
LIMITED (formerly GC Acquisition Limited), a company duly organized and validly
existing under the laws of Bermuda (the "Company"), the other entities
identified on the signature pages hereto under the caption "GUARANTORS" (the
Company together with such other entities, and any entity that shall become a
Guarantor hereunder pursuant to Section 5.11 hereof, being herein called the
"Guarantors" and, together with the Issuer, the "Credit Parties") and WELLS
FARGO BANK MINNESOTA, N.A., as trustee and agent (in such capacities, the
"Trustee") for the benefit of the holders of the Notes (as hereinafter defined).

          Pursuant to an Indenture dated as of December 9, 2003 (as modified
and supplemented and in effect from time to time, the "Indenture") by and
between the Credit Parties and the Trustee, the Issuer has issued $200,000,000
of its 11% Senior Secured Notes due 2006 (the "Notes") and the Guarantors have
unconditionally guaranteed all of the obligations of the Issuer under and in
respect of the Notes.

          To induce the holders of the Notes to accept the same on the terms and
conditions as provided in the Indenture, the Credit Parties wish to grant liens
on and security interests in substantially all of their Property (as hereinafter
defined) as collateral security for the obligations of the Credit Parties under
and in respect of, inter alia, the Indenture and the Notes. Accordingly, the
parties hereto agree as follows:

          Section 1. Definitions.

          (a) Indenture Terms. Terms defined in the Indenture are used herein as
defined therein.

          (b) Certain Uniform Commercial Code Terms. The terms "Accounts",
"Chattel Paper", "Deposit Account", "Document", "Electronic Chattel Paper",
"Equipment", "Fixtures", "General Intangible", "Goods", "Instrument",
"Inventory", "Investment Property", "Letter-of-Credit Right", "Payment
Intangible", "Proceeds" and "Software" have the respective meanings ascribed
thereto in Article 9 of the Uniform Commercial Code. The term "Financial Assets"
shall have the meaning ascribed thereto in Article 8 of the Uniform Commercial
Code.

          (c) Certain other Terms. In addition, as used herein:

          "Collateral" has the meaning assigned to such term in Section 3
     hereof.

<PAGE>

                                       2

          "Copyright Collateral" means all Copyrights, whether now owned or
     hereafter acquired by any Credit Party, including each Copyright identified
     in Annex 4.

          "Copyrights" means all copyrights and copyright registrations,
     including all renewals and extensions thereof, the right to recover for all
     past, present and future infringements thereof, and all other rights of any
     kind whatsoever accruing thereunder or pertaining thereto.

          "Dutch Security Document" means, collectively, each of the following
     documents to be entered into on, and to be dated, the Effective Date (i)
     the Deed of Establishment of a right of Pledge on Registered Shares GC Pan
     European Crossing Holdings B.V., (ii) the Deed of Establishment of a right
     of Pledge on Registered Shares Global Crossing Nederland B.V., (iii) the
     Deed of Establishment of a right of Pledge on Registered Shares GC Pan
     European Crossing Nederland B.V., (iv) the Deed of Establishment of a right
     of Pledge on Registered Shares GC Pan European Crossing Networks B.V., (v)
     the Deed of Establishment of a right of Pledge on Registered Shares Global
     Crossing Venezuela B.V., (vi) the Deed of Establishment of a right of
     Pledge on Registered Shares GT Netherlands B.V., (vii) the Agreement and
     Deed of Non-Possessory Pledge of Assets, (viii) the Agreement and Deed of
     Disclosed Pledge of Intercompany Accounts Receivable dated, (ix) the
     Agreement and Deed of Disclosed Pledge of Credit Balances on Bank Accounts,
     (x) the Agreement and Deed of Undisclosed Pledge of Third Party Accounts
     Receivable and (xi) the Deed of Establishment of a right of Mortgage and
     Pledge.

          "Equity Issuers" means, collectively, (a) the respective corporations,
     partnerships or other entities identified under the names of the Credit
     Parties on Annex 3 under the caption "Equity Issuer" and (b) any other
     entity that shall at any time be a Subsidiary of any Credit Party.

          "Indemnified Parties" has the meaning assigned such term in Section
     5.04 hereof.

          "Intellectual Property" means collectively, all Copyright Collateral,
     all Patent Collateral and all Trademark Collateral, together with (a) all
     inventions, processes, software, production methods, proprietary
     information, know-how and trade secrets; (b) all licenses or user or other
     agreements granted to any Credit Party with respect to any of the
     foregoing, including software licenses, in each case whether now or
     hereafter owned or used including the licenses or other agreements with
     respect to the Copyright Collateral, the Patent Collateral or the Trademark
     Collateral, listed in Annex 7; (c) all information, data, plans,
     blueprints, specifications, designs, drawings, recorded knowledge, surveys,
     engineering reports, test reports, manuals, materials standards, processing
     standards, performance standards, catalogs, computer and automatic
     machinery software and programs with respect to any of the foregoing; (d)
     all field repair data, sales data and other information relating to sales
     or service of products now or hereafter manufactured; (e) all accounting
     information and all media in which or on which any information or knowledge
     or data or records may be recorded or stored and all computer programs used
     for the compilation or printout of such information, knowledge, records or
     data; (f) all licenses, consents, permits, variances, certifications and
     approvals of governmental agencies now or hereafter held by any Credit
     Party; and (g) all causes of action, claims and warranties now or hereafter
     owned or acquired by any Credit Party in respect of any of the items listed
     above.

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<PAGE>

                                       3

          "Motor Vehicles" means motor vehicles, tractors, trailers and other
     like property, whether or not the title thereto is governed by a
     certificate of title or ownership.

          "Patent Collateral" means all Patents, whether now owned or hereafter
     acquired by any Credit Party, including each Patent identified in Annex 5.

          "Patents" means all patents, including the inventions and improvements
     described and claimed therein together with the reissues, divisions,
     continuations, renewals, extensions and continuations-in-part thereof, all
     income, royalties, damages and payments now or hereafter due and/or payable
     under and with respect thereto, including damages and payments for past or
     future infringements thereof, the right to sue for past, present and future
     infringements thereof, and all rights corresponding thereto throughout the
     world.

          "Pledged Indebtedness" means any Indebtedness of any Person held by
     any Credit Party.

          "Pledged Stock" has the meaning assigned to such term in Section 3(c)
     hereof.

          "Secured Obligations" means, collectively, (a) in the case of the
     Issuer, the obligations of the Issuer under and in respect of the Indenture
     and the Notes, (b) in the case of any Guarantor, all present and future
     obligations of such Guarantor under the Indenture and its Note Guarantee,
     and (c) in the case of each Credit Party, all obligations of such Credit
     Party hereunder or under any of the other Security Documents.

          "Stock Collateral" has the meaning assigned to such term in Section
     3(c)(ii) hereof.

          "Trademark Collateral" means all Trademarks, whether now owned or
     hereafter acquired by any Credit Party, including each Trademark identified
     in Annex 6. Notwithstanding the foregoing, the Trademark Collateral does
     not and shall not include any Trademark that would be rendered invalid,
     abandoned, void or unenforceable by reason of its being included as part of
     the Trademark Collateral.

          "Trademarks" means all trade names, trademarks and service marks,
     logos, trademark and service mark registrations, including, without
     limitation, all renewals of trademark and service mark registrations, all
     rights corresponding thereto throughout the world, the right to recover for
     all past, present and future infringements thereof, all other rights of any
     kind whatsoever accruing thereunder or pertaining thereto, together, in
     each case, with the product lines and goodwill of the business connected
     with the use of, and symbolized by, each such trade name, trademark and
     service mark.

          "Uniform Commercial Code" means the Uniform Commercial Code as in
     effect from time to time in the State of New York.

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<PAGE>

                                       4

          Section 2. Representations and Warranties. Each Credit Party
represents and warrants to the Trustee and the Holders that:

          (a) Title and Priority. Such Credit Party legally or beneficially
     owns, or has valid rights as a lessee or licensee (by virtue of
     administrative resolution or through contractual rights) with respect to,
     the Collateral in which it purports to grant a security interest pursuant
     to Section 3 hereof and no Lien exists upon such Collateral except for
     Permitted Liens. To the extent the Uniform Commercial Code is applicable
     thereto, the security interest created pursuant hereto constitutes a valid
     security interest in the Collateral in which such Credit Party purports to
     grant a security interest pursuant to Section 3 hereof, which, upon
     perfection of such security interest under applicable law (to the extent
     such perfection is permitted under applicable law, not contractually
     prohibited and legally possible and not excluded from a perfection
     requirement pursuant to Section 6.02 of the Indenture), will be subject to
     no equal or prior Lien other than Permitted Liens referred to in clauses
     (e), (f), (h), (i), (j), (k), (l), (m), (n) or (o) of the definition of
     such term in Section 1.01 of the Indenture and other than as provided in
     any Intercreditor Agreement.

          (b) Names, Etc. The full and correct legal name, type of organization,
     jurisdiction of organization, organizational ID number (if applicable) and
     mailing address of such Credit Party as of the date hereof are correctly
     set forth in Annex 1. Annex 1 correctly specifies (x) the place of business
     of such Credit Party or, if such Credit Party has more than one place of
     business, the location of the chief executive office of such Credit Party,
     and (y) each country where Equipment, Fixtures, network assets (including
     ducts or cable under IRU's), network equipment, office equipment,
     Inventory, Deposit Accounts, spares and other Goods in excess of $30,000 of
     such Credit Party is located (other than Motor Vehicles constituting
     Equipment, ships, Inventory in transit, Goods in transit and Equipment
     being repaired).

          (c) Changes in Circumstances. Except as specified in Annex 1, such
     Credit Party has not (i) within the period of four months prior to the date
     hereof, changed its "location" (as defined in Section 9-307 of the Uniform
     Commercial Code), (ii) heretofore changed its name, or (iii) heretofore
     become a "new debtor" (as defined in Section 9-102(a)(56) of the Uniform
     Commercial Code) with respect to a currently effective security agreement
     previously entered into by any other Person.

          (d) Pledged Stock. The Pledged Stock, if any, identified under the
     name of such Credit Party in Annex 3 is duly authorized, validly issued,
     fully paid and non-assessable and none of such Pledged Stock is subject to
     any contractual restriction, or any restriction under the charter, by-laws
     or other organizational document of the respective Equity Issuer of such
     Pledged Stock, upon the transfer of such Pledged Stock (except for any
     restriction contained herein or under such organizational documents).

          The Pledged Stock, if any, identified under the name of such Credit
     Party in Annex 3 constitutes all the issued and outstanding shares of
     capital stock of whatever class of such Equity Issuer beneficially owned by
     such Credit Party on the date hereof (whether or not registered in the name
     of such Credit Party); Annex 3 correctly identifies, as at the date hereof,
     the respective Equity Issuers of such Pledged Stock and the respective
     class and par value or other identifying characteristics of the shares

                            Global Security Agreement

<PAGE>

                                       5

     constituting such Pledged Stock and the respective number of shares (and
     registered owners thereof) represented by each such certificate.

          (e) Pledged Indebtedness. The Pledged Indebtedness, if any, identified
     under the name of such Credit Party in Annex 8 constitutes all Indebtedness
     held by any Credit Party that is evidenced by an Instrument and Annex 8
     correctly identifies, as of the date hereof, the respective obligors in
     respect of such Pledged Indebtedness, the amount and maturity thereof, and
     any collateral security or Guarantees therefor.

          (f) Intellectual Property. Annexes 4, 5, and 6, respectively, set
     forth under the name of such Credit Party a complete and correct list of
     all Copyrights, Patents and Trademarks (in each case to the extent
     encompassed within the definition of "Intellectual Property" in Section
     1(b) hereof) owned by such Credit Party on the date hereof, and all
     registrations listed in Annexes 4, 5, and 6, are properly issued and in
     full force and effect. Annex 7 sets forth under the name of such Credit
     Party all licenses and other user agreements pursuant to which such Credit
     Party has been granted the right to use any Copyrights, Patents or
     Trademarks owned by others.

          To such Credit Party's knowledge, (i) except as set forth in Annex 4,
     5 or 6, there is no violation by others of any right of such Credit Party
     with respect to any Copyright, Patent or Trademark listed in Annexes 4, 5,
     and 6, respectively, under the name of such Credit Party and (ii) such
     Credit Party is not infringing upon any copyright, patent or trademark of
     any other Person (other than any other Credit Party, as to which no
     representation or warranty is made) by virtue of the conduct of its
     business; and no proceedings have been instituted, threatened or are
     pending against such Credit Party, and no claim against such Credit Party
     has been received by such Credit Party, alleging any such violation, except
     as may be set forth in Annex 7.

          Section 3. Collateral. As collateral security for the prompt payment
in full when due (whether at stated maturity, by acceleration or otherwise) of
the Secured Obligations, each Credit Party hereby pledges, charges and grants to
the Trustee, for the benefit of the Trustee and the Holders as hereinafter
provided, a security interest in and to all of such Credit Party's right, title
and interest in the following property, whether now owned by such Credit Party
or hereafter acquired and whether now existing or hereafter coming into
existence (all being collectively referred to herein as "Collateral"):

          (a) all Accounts, all General Intangibles, all Deposit Accounts, all
     Instruments, all Documents, all Chattel Paper (whether tangible or
     electronic), all Inventory, all Equipment, all Fixtures;

          (b) all Goods not covered by the preceding clause (a);

          (c) the Equity Interests of the Equity Issuers identified in Annex 3
     under the name of such Credit Party together with all rights, privileges,
     authority and power of such Equity Issuer with respect to such Equity
     Interests, in each case together with the certificates, instruments and
     agreements, if any, evidencing the same (collectively, the "Pledged
     Stock"), together with:

                            Global Security Agreement

<PAGE>

                                       6

               (i) all shares, securities, moneys or property representing a
          dividend on any of the Pledged Stock, or representing a distribution
          or return of capital upon or in respect of the Pledged Stock, or
          resulting from a split-up, revision, reclassification or other like
          change of the Pledged Stock or otherwise received in exchange
          therefor, and any subscription warrants, rights, agreements or options
          issued to the holders of, or otherwise in respect of, the Pledged
          Stock; and

               (ii) without affecting the obligations of such Credit Party under
          any provision prohibiting such action hereunder or under the
          Indenture, in the event of any consolidation, amalgamation or merger
          in which an Equity Issuer is not the surviving corporation, all shares
          of each class of the capital stock of the successor corporation
          (unless such successor corporation is such Credit Party itself) formed
          by or resulting from such consolidation or merger (the Pledged Stock,
          together with all other certificates, shares, securities, properties
          or moneys as may from time to time be pledged or charged hereunder
          pursuant to this clause (ii) and clause (i) above being herein
          collectively called the "Stock Collateral");

          (d) all Investment Property and Financial Assets not covered by clause
     (c) of this Section 3;

          (e) all Intellectual Property;

          (f) all rights, claims and benefits of such Credit Party against any
     Person arising out of, relating to or in connection with the Intellectual
     Property, and Inventory or Equipment purchased by such Credit Party,
     including, without limitation, any such rights, claims or benefits against
     any Person storing or transporting such Inventory or Equipment;

          (g) all Payment Intangibles, Software and all other General
     Intangibles whatsoever not covered by the preceding clauses of this Section
     3;

          (h) all Pledged Indebtedness;

          (i) the balance from time to time in the Asset Sale Proceeds Account,
     the Specified Subsidiary Asset Sale Proceeds Account and the Specified
     Subsidiary Casualty Event Proceeds Account, and all Investment Property and
     Financial Assets at any time held in any of such Accounts;

          (j) all fiber optic submarine cable systems, including cables and
     materials, parts, tools, dies, jigs, fixtures, plans, information and
     contract rights, including all undersea fiber and cable, including all
     undersea fiber and cable in international waters;

          (k) all real property, including all leasehold interests and all
     rights to use any real property interest;

          (l) all other tangible and intangible real and personal property
     whatsoever of such Credit Party; and

                            Global Security Agreement

<PAGE>

                                       7

          (m) all Proceeds, products, offspring, accessions, rents, profits,
     income, benefits, substitutions and replacements of and to any of the
     foregoing and, to the extent related to any of the foregoing, all books,
     correspondence, credit files, records, invoices and other papers (including
     without limitation all tapes, cards, computer runs and other papers and
     documents in the possession or under the control of such Credit Party or
     any computer bureau or service company from time to time acting for such
     Credit Party),

          IT BEING UNDERSTOOD, HOWEVER, that, notwithstanding anything to the
contrary set forth herein, in the Indenture or any other Security Document (but
without limiting the undertakings of the Credit Parties under Article VI of the
Indenture), in no event shall the Collateral consist of, or the security
interest granted under this Section 3 attach, (A) to any lease, license,
governmental authorization, permit, concession, contract, property rights,
application or agreement to which any Credit Party is a party (or to any of its
rights or interests thereunder) if the grant of such security interest would
constitute or result in either (i) the abandonment, invalidation or
unenforceability of any right, title or interest of any Credit Party therein or
(ii) in a breach, cancellation, withdrawal or termination pursuant to the terms
of, or a default under, any such lease, license, governmental authorization,
permit, concession, contract, property rights, application or agreement (except
to the extent that any such term would be rendered ineffective pursuant to, or
any such breach, cancellation, withdrawal or termination would be overridden by,
Sections 9-406, 9-407, 9-408 or 9-409 of the Uniform Commercial Code or other
applicable law), (B) without limiting the provisions of Section 6.02 of the
Indenture, to any Property in any jurisdiction, to the extent that obtaining a
Lien upon such Property in such jurisdiction is prohibited under applicable law,
or requires the obtaining of a governmental approval (which governmental
approval has not yet been obtained), (C) to any Excluded Collateral or (D) to
any Property located in The Netherlands or, in the case of Receivables, governed
by Netherlands law, and over which a valid security interest is or will be
created by any Dutch Security Document.

          It is contemplated that, with respect to Collateral of any Credit
Party that (x) consists of any real property or real property interest (wherever
located), (y) any Collateral of any Credit Party that may be located outside of
the United States, and (z) any Collateral wherever located of any Credit Party
that may be organized or that conducts business outside of the United States,
such Credit Party will concurrently with the execution and delivery of this
Agreement (but subject to Section 6.02 of the Indenture) execute and deliver
such additional security agreements, pledge agreements, assignments, mortgages
and other similar instruments or documents as shall be necessary or appropriate
(and permitted under applicable law) in order to create, perfect and make
enforceable Liens upon and other security interests in the Collateral owned by
such Credit Party under the law of the jurisdiction in which such Collateral is
located or in which such Credit Party is organized or conducts business. Any
such additional security agreements, pledge agreements, assignments, mortgages
and similar instruments and documents shall be deemed to supplement and not
supersede the Liens and security interests provided herein.

          Anything herein to the contrary notwithstanding, no Credit Party shall
be required to perform any action which is illegal or which may violate any
applicable law or that carries a material risk of jeopardizing the rights it
holds in the Collateral.

          Section 4. Further Assurances; Remedies. In furtherance of the grant
of the pledge, charge and security interest pursuant to Section 3 hereof, the
Credit Parties hereby jointly

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<PAGE>

                                       8

and severally agree with the Trustee (but subject to the provisions of Section
6.02 of the Indenture) as follows:

          4.01 Delivery and Other Perfection. Each Credit Party shall:

          (a) if any of the shares, securities, moneys or property required to
     be pledged and charged by such Credit Party under clauses (c)(i) and
     (c)(ii) of Section 3 hereof are received by such Credit Party forthwith,
     either (x) transfer and deliver to the Trustee (or to the Agent or third
     party under any Intercreditor Agreement as provided in Article III thereof)
     such shares, securities, moneys or property so received by such Credit
     Party (together with the certificates, if any, for any such shares and
     securities duly endorsed in blank or accompanied by undated stock powers
     duly executed in blank), all of which thereafter shall be held by the
     Trustee (or the Agent or third party), pursuant to the terms of this
     Agreement, as part of the Collateral or (y) take such other action as shall
     be necessary to duly record the Lien created hereunder in such shares,
     securities, moneys or property in said clauses (c)(i) and (c)(ii),
     including, with respect to the Lien on the shares of an Equity Issuer which
     are not represented by certificates, the registration in the shareholders
     register of such Equity Issuer of appropriate entries evidencing said Lien;

          (b) deliver and pledge to the Trustee (or to the Agent or third party
     under any Intercreditor Agreement as provided in Article III thereof) any
     and all Instruments (other than checks) constituting part of the Collateral
     in which such Credit Party purports to grant a security interest hereunder,
     endorsed and/or accompanied by such instruments of assignment and transfer
     in such form and substance necessary to effectuate the security interest
     granted hereunder; provided, that so long as no Event of Default shall have
     occurred and be continuing, unremedied and unwaived, such Credit Party may
     retain for collection in the ordinary course any Instruments received by
     such Credit Party in the ordinary course of its business and the Trustee
     shall, promptly upon request of such Credit Party through the Company, make
     arrangements against trust receipt or like document for making any
     Instrument pledged by such Credit Party available to such Credit Party for
     purposes of presentation, collection or renewal;

          (c) deliver and pledge to the Trustee (or to the Agent or third party
     under any Intercreditor Agreement as provided in Article III thereof) any
     and all promissory notes or other instruments constituting part of the
     Collateral and evidencing any of the Pledged Indebtedness in excess of
     $200,000, endorsed and/or accompanied by such instruments of assignment and
     transfer in such form as shall be necessary to perfect the Lien of the
     Trustee in such promissory notes and instruments;

          (d) give, execute, deliver, file, record, authorize or obtain all such
     financing statements, notices, instruments, documents, agreements or
     consents or other papers as, subject to Section 6.02 of the Indenture,
     shall be necessary to create, preserve, perfect or validate the security
     interest granted pursuant hereto and the priority thereof or to enable the
     Trustee to exercise and enforce its rights hereunder with respect to such
     security interest, including, without limitation, causing any or all of the
     Stock Collateral to be transferred of record into the name of the Trustee
     or its nominee (and the Trustee agrees that if any Stock Collateral is
     transferred into its name or the name of its nominee, the Trustee will
     thereafter promptly upon request therefor by the Company give to such

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                                       9

     Credit Party copies of any notices and communications received by it with
     respect to the Stock Collateral pledged and charged by such Credit Party
     hereunder);

          (e) keep accurate books and records relating to the Collateral, and
     stamp or otherwise mark such books and records in such manner as shall be
     necessary in order to reflect the security interests granted by this
     Agreement;

          (f) following the occurrence and during the continuance, unremedied
     and unwaived, of an Event of Default, permit representatives of the
     Trustee, upon reasonable notice, at any time during normal business hours
     to inspect and make abstracts from its books and records pertaining to the
     Collateral, and permit representatives of the Trustee to be present at such
     Credit Party's place of business to receive copies of all communications
     and remittances relating to the Collateral, and forward copies of any
     notices or communications received by such Credit Party with respect to the
     Collateral, all in such manner as the Trustee may reasonably require; and

          (g) subject to Section 6.02 of the Indenture, execute and deliver and
     cause to be filed, such continuation statements, and do such other acts and
     things, as may be necessary to maintain the perfection and priority of the
     security interest granted pursuant hereto.

          Anything herein to the contrary notwithstanding, it is understood and
agreed that, as provided in Section 6.03(a) of the Indenture:

          (i) as to Property of any Credit Party located in any jurisdiction
     owned by such Credit Party on the date hereof that is not covered by the
     Lien of a particular Security Document other than this Agreement, such
     Credit Party shall be deemed to have complied with the requirements of this
     Section 4.01 if, as contemplated by Exhibit F to the Indenture, the
     Administrative Agent and the Official Creditors' Committee confirm in
     writing to the Trustee that the conditions set forth in said Exhibit F have
     been satisfied;

          (ii) as to Property of any Credit Party located in any jurisdiction,
     whether now owned or hereafter acquired, that is covered by the Lien of a
     particular Security Document other than this Agreement (or that is
     contemplated by such Security Document to be covered by such Lien if
     acquired after the date hereof), such Credit Party shall be deemed to have
     complied with the requirements of this Section 4.01 if such Credit Party
     complies with the requirements of such Security Document;

          (iii) as to all other Property hereafter acquired by any Credit Party,
     such Credit Party shall (subject to Section 6.02 of the Indenture) comply
     with the requirements of this Section 4.01;

          (iv) as to any contract or agreement to which any Credit Party is a
     party on the date hereof that requires the consent of a third party in
     order to create a lien in such contract or agreement, such Credit Party
     shall be deemed to have complied with the requirements of this Section 4.01
     if, after utilizing commercially reasonable efforts in an attempt to so
     obtain such consent, as contemplated by Exhibit F to the Indenture, the
     Administrative Agent and the Official Creditors' Committee confirm in
     writing to the Trustee that the conditions set forth in said Exhibit F have
     been satisfied; and

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                                       10

          (v) as to any contract or agreement to which any Credit Party becomes
     a party after the date hereof that requires the consent of a third party in
     order to create a Lien in such contract or agreement, such Credit Party
     shall be deemed to have complied with the requirements of this Section
     4.01, notwithstanding that such consent has been refused, if it shall have
     used commercially reasonable efforts to obtain such consent (and shall so
     certify in the first Officers' Certificate delivered pursuant to Section
     6.03(c)(ii)(B) of the Indenture after the date of such refusal).

          4.02 Other Financing Statements and Liens. Except for Permitted Liens,
no Credit Party shall (i) file or suffer to be on file, or authorize or permit
to be filed or to be on file, in any jurisdiction, any financing statement or
like instrument or (ii) create or permit the creation of any Lien or allow any
Lien to subsist, with respect to the Collateral in which the Trustee is not
named as the sole secured party for the benefit of the Trustee and the Holders.

          4.03 Preservation of Rights. The Trustee shall not be required to take
steps necessary to preserve any rights against prior parties to any of the
Collateral, provided that the Trustee shall cooperate with the Credit Parties in
any request for documentation or evidence in any action taken by a Credit Party
to protect or preserve its rights in the Collateral, to the extent such request
is made pursuant to an Issuer Order.

          4.04 Special Provisions Relating to Certain Collateral.

          (a) Stock Collateral. The Credit Parties will cause the Stock
Collateral to constitute at all times 100% of all the total number of shares of
Capital Stock of each Equity Issuer then issued and outstanding held by the
Credit Parties.

          So long as no Event of Default shall have occurred and be continuing,
unremedied and unwaived, the Credit Parties shall have the right to exercise all
voting, consensual and other powers of ownership pertaining to the Stock
Collateral for all purposes not inconsistent with the terms of this Agreement,
the Indenture or any other Security Document or any other instrument or
agreement referred to herein or therein, provided that the Credit Parties
jointly and severally agree that they will not vote the Stock Collateral in any
manner that results in a violation of the terms of this Agreement, the
Indenture, the Security Documents or any such other instrument or agreement; and
the Trustee shall execute and deliver to the Credit Parties or cause to be
executed and delivered to the Credit Parties all such proxies, powers of
attorney, dividend and other orders, and all such instruments, without recourse,
as the Credit Parties may reasonably request pursuant to an Issuer Request for
the purpose of enabling the Credit Parties to exercise the rights and powers
that they are entitled to exercise pursuant to this Section 4.04.

          (b) Intellectual Property. Notwithstanding the pledge of its
Intellectual Property hereunder and any requirement contained in the Indenture
or any other Security Document, until notice to the Credit Parties has been
given by the Trustee following the occurrence and during the continuance,
unremedied and unwaived, of an Event of Default, each Credit Party shall have
the right to exploit and use the Intellectual Property in connection with its
business, including but not limited to the development, marketing, promotion,
distribution and sale of the underlying services related to such Intellectual
Property.

                            Global Security Agreement

<PAGE>

                                       11

          4.05 Events of Default, Etc. During the period during which an Event
of Default shall have occurred and be continuing, unremedied and unwaived:

          (a) each Credit Party shall, at the request of the Trustee, assemble
     the Collateral owned by it at such place or places, reasonably convenient
     to both the Trustee and such Credit Party, designated in the Trustee's
     request;

          (b) the Trustee may make any reasonable compromise or settlement
     deemed desirable with respect to any of the Collateral and may extend the
     time of payment, arrange for payment in installments, or otherwise modify
     the terms of, any of the Collateral;

          (c) the Trustee shall have all of the rights and remedies with respect
     to the Collateral of a secured party under the Uniform Commercial Code
     (whether or not the Uniform Commercial Code is in effect in the
     jurisdiction where the rights and remedies are asserted) and such
     additional rights and remedies to which a secured party is entitled under
     the laws in effect in any jurisdiction where any rights and remedies
     hereunder or under any of the other Security Documents may be asserted,
     including the right, to the fullest extent permitted by applicable law, to
     exercise all voting, consensual and other powers of ownership pertaining to
     the Collateral as if the Trustee were the sole and absolute owner thereof
     (and each Credit Party agrees to take all such action as may be appropriate
     to give effect to such right);

          (d) the Trustee may, in its name or in the name of any Credit Party or
     otherwise, demand, sue for, collect or receive any money or property at any
     time payable or receivable on account of or in exchange for any of the
     Collateral, but shall be under no obligation to do so; and

          (e) the Trustee may, upon ten Business Days' prior written notice to
     the Credit Parties of the time and place, with respect to the Collateral or
     any part thereof which shall then be or shall thereafter come into the
     possession, custody or control of the Trustee, or any of its agents, sell,
     lease, assign or otherwise dispose of all or any part of such Collateral,
     at such place or places as the Trustee deems best, and for cash or for
     credit or for future delivery (without thereby assuming any credit risk),
     at public or private sale, without demand of performance or notice of
     intention to effect any such disposition or of the time or place thereof
     (except such notice as is required above or by applicable statute and
     cannot be waived), and the Trustee or any other Holder or anyone else may
     be the purchaser, lessee, assignee or recipient of any or all of the
     Collateral so disposed of at any public sale (or, to the extent permitted
     by law, at any private sale) and thereafter, to the fullest extent
     permitted by law, hold the same absolutely, free from any claim or right of
     whatsoever kind, including any right or equity of redemption (statutory or
     otherwise), of the Credit Parties, any such demand, notice and right or
     equity being hereby expressly waived and released, to the fullest extent
     permitted by law. The Trustee may, without notice or publication, adjourn
     any public or private sale or cause the same to be adjourned from time to
     time by announcement at the time and place fixed for the sale, and such
     sale may be made at any time or place to which the sale may be so
     adjourned.

          In the event of any sale, assignment, or other disposition of any of
     the Trademark Collateral, the goodwill connected with and symbolized by the
     Trademark Collateral

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<PAGE>

                                       12

     subject to such disposition shall be included, and the Credit Parties shall
     supply to the Trustee or its designee, for inclusion in such sale,
     assignment or other disposition, all Intellectual Property relating to such
     Trademark Collateral.

The proceeds of each collection, sale or other disposition under this Section
4.05 shall be applied in accordance with Section 4.09 hereof.

          The Credit Parties recognize that, by reason of certain prohibitions
contained in the Securities Act of 1933, as amended, and applicable state
securities laws, the Trustee may be compelled, with respect to any sale of all
or any part of the Collateral, to limit purchasers to those who will agree,
among other things, to acquire the Collateral for their own account, for
investment and not with a view to the distribution or resale thereof. The Credit
Parties acknowledge that any such private sales may be at prices and on terms
less favorable to the Trustee than those obtainable through a public sale
without such restrictions, and, notwithstanding such circumstances, agree that
any such private sale shall be deemed to have been made in a commercially
reasonable manner and that the Trustee shall have no obligation to engage in
public sales and no obligation to delay the sale of any Collateral for the
period of time necessary to permit the Credit Parties or issuer thereof to
register it for public sale.

          4.06 Deficiency. If the proceeds of sale, collection or other
realization of or upon the Collateral pursuant to Section 4.05 hereof are
insufficient to cover the costs and expenses of such realization and the payment
in full of the Secured Obligations, the Credit Parties shall remain liable for
any deficiency.

          4.07 Locations; Names. Without at least 30 days' prior written notice
to the Trustee, and (in the case of a change of its name) delivery of an Opinion
of Counsel and an Issuer Order identifying any action required to be taken by
such Credit Party or the Trustee to perfect or continue the perfection of the
Liens hereunder granted by such Credit Party and protect the priority thereof,
no Credit Party shall change its "location" (as defined in Section 9-307 of the
Uniform Commercial Code) or change its name from the name shown as its current
legal name on Annex 1.

          Without the prior written consent of the Trustee, any Credit Party may
remove items of Collateral outside of any jurisdiction in which such Credit
Party conducts business, or in which such items are located, in order to have
them repaired or upgraded, subject to the obligation of returning such items to
their original location in such jurisdiction as soon as their repair or upgrade
has been completed and, if required in order to transport or relocate any such
item of Collateral, the Trustee shall, upon delivery to it of an Issuer Order
requesting a release (which shall state that such release is authorized under
this Section 4.07), promptly execute and deliver to such Credit Party such
release statement and such other documentation as shall be specified by such
Credit Party in such Issuer Order to effect the temporary release of the Lien on
such item of Collateral in order that it may be removed or relocated.

          4.08 Private Sale. The Trustee and the Holders shall incur no
liability as a result of the sale of the Collateral, or any part thereof, at any
private sale pursuant to Section 4.05 hereof conducted in a commercially
reasonable manner. Each Credit Party hereby waives any claims against the
Trustee or any Holder arising by reason of the fact that the price at which the
Collateral may have been sold at such a private sale was less than the price
which might have been obtained at a public sale or was less than the aggregate
amount of the Secured Obligations,

                            Global Security Agreement

<PAGE>

                                       13

even if the Trustee accepts the first offer received and does not offer the
Collateral to more than one offeree.

          4.09 Application of Proceeds. The proceeds of any collection, sale or
other realization of all or any part of the Collateral pursuant hereto, and any
other cash at the time held by the Trustee under this Section 4, shall be
applied by the Trustee in the manner set forth in Article IX of the Indenture.

          4.10 Attorney-in-Fact. Without limiting any rights or powers granted
by this Agreement to the Trustee while no Event of Default has occurred and is
continuing, upon the occurrence and during the continuance, unremedied and
unwaived, of any Event of Default the Trustee is hereby appointed the
attorney-in-fact of each Credit Party for the purpose of carrying out the
provisions of this Section 4 and taking any action and executing any instruments
which the Trustee may reasonably deem necessary or advisable to accomplish the
purposes hereof, which appointment as attorney-in-fact is irrevocable and
coupled with an interest. Without limiting the generality of the foregoing, so
long as the Trustee shall be entitled under this Section 4 to make collections
in respect of the Collateral, the Trustee shall have the right and power to
receive, endorse and collect all checks made payable to the order of any Credit
Party representing any dividend, payment or other distribution in respect of the
Collateral or any part thereof and to give full discharge for the same.

          4.11 Perfection. Each Credit Party consents that Uniform Commercial
Code financing statements may be filed describing the Collateral as "all assets"
or "all personal property" of such Credit Party (provided that no such
description shall be deemed to modify the description of Collateral set forth in
Section 3 hereof).

          Anything herein to the contrary notwithstanding, the obligations of
the Credit Parties to take any action to perfect the Liens granted hereunder and
under any other Security Document on any Collateral shall be subject to the
provisions of Sections 6.02 and 6.03 of the Indenture.

          4.12 Certain Releases of Collateral.

          (a) Releases Upon Asset Sales, Etc. If at any time a Credit Party
consummates an Asset Sale, a Specified Subsidiary Asset Sale, or a Qualified
Receivables Transaction, in accordance with the terms of the Indenture and
satisfies all of the conditions precedent set forth in Section 6.05(b) of the
Indenture with respect thereto, the Trustee shall, upon the request of such
Credit Party, execute, deliver or acknowledge any necessary or proper
instruments of termination, satisfaction or release prepared by such Credit
Party reasonably required to effect the release of the Liens on the Collateral
which is the subject of such Asset Sale, Specified Subsidiary Asset Sale, or
Qualified Receivables Transaction.

          (b) Releases Upon Other Asset Sales. If at any time a Credit Party
sells, transfers, leases, conveys, substitutes, converts, abandons or otherwise
disposes of any item of Collateral in a transaction (i) not deemed to be an
Asset Sale under the Indenture as set forth in clauses (a) through (f),
inclusive, and (h) of the definition of "Asset Sale" therein or (ii) otherwise
permitted under the Indenture and for which such Credit Party has complied with
all requirements in respect thereof (each such transaction listed in clause (i)
and (ii) hereinabove,

                            Global Security Agreement

<PAGE>

                                       14

a "Permitted Sale"), any Lien on such item of Collateral shall be automatically
released and, if a formal, documented termination of release shall be necessary,
the Trustee shall, upon delivery to it of an Issuer Order requesting such
release (which shall state that such release is authorized under this Section
4.12(b)), promptly execute and deliver to such Credit Party upon the occurrence
of such Permitted Sale such termination or release statements and such other
documentation as shall be specified by such Credit Party in such Issuer Order to
effect the termination and release of the Liens on such item of Collateral which
is the subject of the Permitted Sale.

          4.13 Termination. When all Secured Obligations shall have been paid in
full or otherwise discharged, this Agreement shall terminate and the Trustee
shall forthwith cause to be assigned, transferred and delivered, against receipt
but without any recourse, warranty or representation whatsoever, any remaining
Collateral and money received in respect thereof, to or on the order of the
respective Credit Party. The Trustee shall, at the expense of the Company, also
execute and deliver to the respective Credit Party upon such termination such
Uniform Commercial Code termination statements and such other documentation as
shall be reasonably requested by the respective Credit Party to effect the
termination and release of the Liens on the Collateral. Upon completion by the
Trustee of the duties enumerated in this Section 4.12 in accordance herewith,
the Trustee shall thenceforth be relieved of all further obligations under this
Agreement.

          Section 5. Miscellaneous.

          5.01 Notices. All notices, waivers, requests, consents, demands,
directions and other instruments delivered pursuant to the terms of this
Agreement and the other Security Documents shall be in writing in the English
language or accompanied by a certified English translation (which English
translation shall be considered the original instrument and shall control in
case of any conflict between the English and foreign language versions) and
telecopied or delivered to the respective parties hereto as provided in Section
12.02 of the Indenture. All such communications shall be deemed to have been
given at the times specified in said Section 12.02.

          5.02 No Waiver. No failure on the part of the Trustee or any Holder to
exercise, and no course of dealing with respect to, and no delay in exercising,
any right, power or remedy hereunder shall operate as a waiver thereof; nor
shall any single or partial exercise by the Trustee or any Holder of any right,
power or remedy hereunder preclude any other or further exercise thereof or the
exercise of any other right, power or remedy. The remedies herein are cumulative
and are not exclusive of any remedies provided by law.

          5.03 Amendments, Etc. The terms of this Agreement may be waived,
altered or amended only by an instrument in writing duly executed by each Credit
Party and the Trustee in accordance with the provisions of Article XI of the
Indenture. Any such amendment or waiver shall be binding upon the Trustee, each
Holder and each Credit Party.

          5.04 Expenses. The Credit Parties jointly and severally agree to
indemnify and reimburse the Trustee, its officers, directors, employees,
representatives and agents (collectively, the "Indemnified Parties") for all
reasonable costs and expenses (including the reasonable fees and expenses of
legal counsel) incurred by such Indemnified Parties in connection with (i) any
filing, registration, recording or perfection of any security interest
contemplated by any Security

                            Global Security Agreement

<PAGE>

                                       15

Document or any other document referred to therein (including the reasonable
fees and expenses of counsel in any jurisdiction retained by the Trustee in
connection therewith), (ii) any Default and any enforcement or collection
proceeding resulting therefrom, including all manner of participation in or
other involvement with (w) performance by the Trustee of any obligations of the
Credit Parties in respect of the Collateral that the Credit Parties have failed
or refused to perform (to the extent that, taking into account Section 6.02 of
the Indenture, performance of such obligations is required), (x) bankruptcy,
insolvency, receivership, foreclosure, winding up or liquidation proceedings, or
any actual or attempted sale, or any exchange, enforcement, collection,
compromise or settlement in respect of any of the Collateral, and for the care
of the Collateral and defending or asserting rights and claims of the Trustee in
respect thereof, by litigation or otherwise, including expenses of insurance,
(y) judicial or regulatory proceedings and (z) workout, restructuring or other
negotiations or proceedings (whether or not the workout, restructuring or
transaction contemplated thereby is consummated) and (iii) the enforcement of
this Section 5.04, and all such costs and expenses shall be Secured Obligations
entitled to the benefits of the collateral security provided pursuant to Section
3 hereof.

          5.05 Successors and Assigns. This Agreement shall be binding upon and
inure to the benefit of the respective successors and assigns of each Credit
Party, the Trustee and each Holder (provided that (i) no Credit Party shall
assign or transfer its rights or obligations hereunder without the prior written
consent of the Trustee, and (ii) any assignment by the Trustee shall be made in
accordance with the applicable provisions of the Indenture).

          5.06 Counterparts. This Agreement may be executed in any number of
counterparts, all of which taken together shall constitute one and the same
instrument and any of the parties hereto may execute this Agreement by signing
any such counterpart.

          5.07 Governing Law. This Agreement shall be governed by, and construed
in accordance with, the law of the State of New York.

          5.08 Captions. The captions and section headings appearing herein are
included solely for convenience of reference and are not intended to affect the
interpretation of any provision of this Agreement.

          5.09 Agents and Attorneys-in-Fact. The Trustee may employ agents and
attorneys-in-fact in connection herewith and shall not be responsible for the
gross negligence or willful misconduct of any such agents or attorneys-in-fact
selected by it in good faith. The reasonable fees and expenses of such agents
and attorneys shall be reimbursed pursuant to Section 5.04 hereof.

          5.10 Severability. If any provision hereof is invalid and
unenforceable in any jurisdiction, then, to the fullest extent permitted by law,
(a) the other provisions hereof shall remain in full force and effect in such
jurisdiction and (b) the invalidity or unenforceability of any provision hereof
in any jurisdiction shall not affect the validity or enforceability of such
provision in any other jurisdiction.

          5.11 Additional Guarantors. As contemplated by Section 4.19 of the
Indenture, if at any time after the date of the Indenture the Company shall form
or acquire any new Subsidiary that shall constitute a Material Subsidiary, or if
after the date of the Indenture any existing Subsidiary not a Material
Subsidiary shall become a Material Subsidiary, the Company will

                            Global Security Agreement

<PAGE>

                                       16

within three Business Days thereof cause such new or existing Subsidiary to
execute and deliver to the Trustee a Guarantee Supplement in substantially the
form of Exhibit B to the Indenture, and thereby to become a "Guarantor" under
the Indenture and this Agreement, and (i) deliver such Opinions of Counsel in
New York and applicable foreign jurisdictions as to (x) the valid existence of
such Guarantor, (y) the due authorization, execution and enforceability of such
Guarantee Supplement and (z) such other matters as the Trustee may reasonably
request and (ii) take such action (including executing and delivering such
Security Documents, instruments of further assurance and amendments or
supplements thereto, and delivering such additional Opinions of Counsel and
other documents or instruments as required under Section 6.03(c) of the
Indenture), in order that such new or existing Subsidiary shall grant Liens on
all Property owned by it then existing or thereafter arising that are included
in the definition of "Collateral" in Section 3 hereof.

          Accordingly, upon the execution and delivery of any such Guarantee
Supplement by any such Subsidiary, such Subsidiary shall automatically and
immediately, and without any further action on the part of any Person, become a
"Guarantor" and a "Credit Party" for all purposes of this Agreement, and Annexes
1 through 8, inclusive, hereto shall be deemed to be supplemented in the manner
specified in such Guarantee Supplement. In addition, upon execution and delivery
of any such Guarantee Supplement, the new Guarantor makes the representations
and warranties set forth in Section 2 hereof.

          5.12 Trustee Rights. The rights, privileges, immunities, indemnities
and standard of care provided to the Trustee under Article VIII of the Indenture
shall, to the extent applicable, apply in this Agreement and to the Trustee's
acts and omissions related to this Agreement, the Collateral and the Security
Documents as if fully set forth herein. In addition to the foregoing, the
parties hereto agree that:

          (a) the permissive rights of the Trustee to do things enumerated in
     this Agreement shall not be construed as a duty and the Trustee shall not
     be answerable for other than its gross negligence or willful misconduct;

          (b) except as expressly instructed by the Holders or the Issuer or any
     other Credit Party, the Trustee shall have no obligation to give, execute,
     deliver, file, record, authorize or obtain any financing statements,
     notices, instruments, documents, agreements, consents or other papers as
     shall be necessary to create, preserve, perfect or validate the security
     interest granted pursuant hereto or to enable the Trustee to exercise and
     enforce its rights hereunder with respect to such pledge and security
     interest, and the Trustee have no responsibility or liability (i) in
     connection with the acts or omissions of the Credit Parties in respect of
     the foregoing or (ii) for or with respect to the legality, validity and
     enforceability of any security interest created in the Collateral or the
     perfection and priority of such security interest; and

          (c) the Trustee shall have no obligation to obtain title to any piece
     of real property by foreclosure, deed in lieu of foreclosure or otherwise,
     or take any other action with respect to any real property, if, in its
     reasonable, good faith judgment, it shall determine that, as a result of
     such action, the Trustee would be liable, in its individual capacity for
     any environmental liability in connection with, or responsibility for the

                            Global Security Agreement

<PAGE>

                                       17

     clean-up or remediation of, such real property under any applicable
     environmental laws and regulations.

          5.13 Liens Junior to any Working Capital Facility. Notwithstanding
anything to the contrary contained herein or under applicable law as to the
priority of the Lien created by this Agreement, the Trustee acknowledges and
agrees, for and on behalf of the Holders of the Notes, that such Lien is subject
and subordinate to any Lien securing the obligations of the Credit Parties under
and in respect of the Working Capital Facility in the manner and to the extent
provided in the applicable Intercreditor Agreement.

          5.14 Enforcement. By its acceptance of the benefits of this Agreement,
except to the extent otherwise provided in Section 7.06 of the Indenture, each
Holder agrees that this Agreement may only be enforced by the Trustee, and that
no Holder shall have any right individually to enforce or seek to enforce this
Agreement or to realize upon the Collateral or other security given to secure
the payment and performance of the Secured Obligations.

                            Global Security Agreement

<PAGE>

                                       18

          IN WITNESS WHEREOF, the parties hereto have caused this Global
Security Agreement to be duly executed in their respective capacities as set
forth below as of the date first written above.

                                        ISSUER

                                        GLOBAL CROSSING NORTH
                                           AMERICAN HOLDINGS, INC.


                                        By: /s/ John B. McShane
                                            ------------------------------------
                                            Name: John B. McShane
                                            Title: Authorized Signatory


                                        GUARANTORS

                                        GLOBAL CROSSING LIMITED


                                        By: /s/ John B. McShane
                                            ------------------------------------
                                            Name: John B. McShane
                                            Title: Exec. VP & General Counsel

                            Global Security Agreement

<PAGE>

                                       19

     U.S. GUARANTORS

ALC COMMUNICATIONS CORPORATION                 BUDGET CALL LONG DISTANCE, INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


BUSINESS TELEMANAGEMENT, INC.                  GC DEV. CO., INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


GC PACIFIC LANDING CORP.                       GLOBAL CROSSING ADVANCED
                                                  CARD SERVICES, INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------            -----------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


GLOBAL CROSSING BANDWIDTH, INC.                GLOBAL CROSSING BILLING, INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


GLOBAL CROSSING                                GLOBAL CROSSING EMPLOYEE
   DEVELOPMENT CO.                                SERVICES INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


GLOBAL CROSSING                                GLOBAL CROSSING HOLDINGS
   GLOBALCENTER HOLDINGS, INC.                    USA, LLC


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President

                            Global Security Agreement

<PAGE>

                                       20

GLOBAL CROSSING INTERNET                       GLOBAL CROSSING LATIN
   DIAL-UP, INC.                                  AMERICA & CARIBBEAN CO.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


GLOBAL CROSSING LOCAL                          GLOBAL CROSSING NORTH
   SERVICES, INC.                                 AMERICA, INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


GLOBAL CROSSING NORTH                          GLOBAL CROSSING
  AMERICAN NETWORKS, INC.                         TELECOMMUNICATIONS, INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


GLOBAL CROSSING TELEMANAGEMENT, INC.           GLOBAL CROSSING USA INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


GT LANDING CORP.                               GT LANDING II CORP.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


INTERNATIONAL OPTICAL NETWORK, L.L.C.          IXNET, INC.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President

                           Global Security Agreement

<PAGE>

                                       21

MAC LANDING CORP.                              PAC LANDING CORP.


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


RACAL TELECOMMUNICATIONS INC.                  SUBSIDIARY TELCO, LLC


By /s/ Michael Shortley                        By /s/ Michael Shortley
   ------------------------------------           ------------------------------
   Name: Michael Shortley                         Name: Michael Shortley
   Title: Vice President                          Title: Vice President


US CROSSING, INC.


By /s/ Michael Shortley
   ------------------------------------
   Name: Michael Shortley
   Title: Vice President

                            Global Security Agreement

<PAGE>

                                       22

BERMUDAN GUARANTORS

ATLANTIC CROSSING HOLDINGS LTD.                ATLANTIC CROSSING LTD.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


ATLANTIC CROSSING II LTD.                      GLOBAL CROSSING HOLDINGS LIMITED


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GLOBAL CROSSING                                GLOBAL CROSSING NETWORK
   INTERNATIONAL, LTD.                            CENTER LTD.


By /s/ David Sheffey                           By  /s/ David Sheffey
   ------------------------------------            -----------------------------
   Name: David Sheffey                             Name: David Sheffey
   Title: Attorney-in-fact                         Title: Attorney-in-fact


GLOBAL CROSSING PORTFOLIO                      MID-ATLANTIC CROSSING
   HOLDINGS LTD.                                  HOLDINGS LTD.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


MID-ATLANTIC CROSSING LTD.                         PAC PANAMA LTD.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       23

PAN AMERICAN CROSSING HOLDINGS LTD.            PAN AMERICAN CROSSING LTD.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


SOUTH AMERICAN CROSSING HOLDINGS LTD.          SOUTH AMERICAN CROSSING LTD.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact

CANADIAN GUARANTORS

AMERITEL MANAGEMENT, INC.                      GLOBAL CROSSING
                                                  CONFERENCING-CANADA, LTD.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Assistant Secretary                     Title: Assistant Secretary


GLOBAL CROSSING TELECOMMUNICATIONS-            GLOBAL CROSSING WORLDWIDE
  CANADA, LTD.                                    CUSTOMER HELP DESK CANADA LTD.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Assistant Secretary                     Title: Assistant Secretary

                            Global Security Agreement

<PAGE>

                                       24

UK GUARANTORS

Executed as a deed by                          Executed as a deed by
ATLANTIC CROSSING HOLDINGS                     GC PAN EUROPEAN CROSSING
  U.K. LIMITED                                    UK LTD.


By /s/ Terrence L. Dugan                       By /s/ Terrence L. Dugan
   ------------------------------------           ------------------------------
   Name: Terrence L. Dugan                        Name: Terrence L. Dugan
   Title: Attorney-in-fact                        Title: Attorney-in-fact


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


Executed as a deed by                          Executed as a deed by
GEOCONFERENCE LIMITED                          GLOBAL CROSSING (BIDCO) LIMITED


By /s/ Terrence L. Dugan                       By /s/ Terrence L. Dugan
   ------------------------------------           ------------------------------
   Name: Terrence L. Dugan                        Name: Terrence L. Dugan
   Title: Attorney-in-fact                        Title: Attorney-in-fact


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


Executed as a deed by                          Executed as a deed by
GLOBAL CROSSING CONFERENCING LIMITED           GLOBAL CROSSING EUROPE LIMITED


By /s/ Terrence L. Dugan                       By /s/ Terrence L. Dugan
   ------------------------------------           ------------------------------
   Name: Terrence L. Dugan                        Name: Terrence L. Dugan
   Title: Attorney-in-fact                        Title: Attorney-in-fact


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       25

Executed as a deed by                          Executed as a deed by
GLOBAL CROSSING IXNET EMEA                     GLOBAL CROSSING NETWORK
   HOLDINGS LIMITED                               CENTER (UK) LTD.


By /s/ Terrence L. Dugan                       By /s/ Terrence L. Dugan
   ------------------------------------           ------------------------------
   Name: Terrence L. Dugan                        Name: Terrence L. Dugan
   Title: Attorney-in-fact                        Title: Attorney-in-fact


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


Executed as a deed by                          Executed as a deed by
GLOBAL CROSSING (UK) TELECOMMUNICATIONS        GT U.K. LTD.
   LIMITED


By  /s/ Terrence L. Dugan                      By /s/ Terrence L. Dugan
   ------------------------------------           ------------------------------
   Name: Terrence L. Dugan                        Name: Terrence L. Dugan
   Title: Attorney-in-fact                        Title: Attorney-in-fact


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


Executed as a deed by                          Executed as a deed by
IXNET UK LIMITED                               MID-ATLANTIC CROSSING
                                                 HOLDINGS UK LTD.


By /s/ Terrence L. Dugan                       By /s/ Terrence L. Dugan
   ------------------------------------           ------------------------------
   Name: Terrence L. Dugan                        Name: Terrence L. Dugan
   Title: Attorney-in-fact                        Title: Attorney-in-fact


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       26

Executed as a deed by
PAN AMERICAN CROSSING UK LTD.


By /s/ Terrence L. Dugan
   ------------------------------------
   Name: Terrence L. Dugan
   Title: Attorney-in-fact


By /s/ David Sheffey
   ------------------------------------
   Name: David Sheffey
   Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       27

IRISH GUARANTORS:

SIGNED, SEALED and DELIVERED by                SIGNED, SEALED and DELIVERED by
GC HOLDING SPV by its duly appointed           GLOBAL CROSSING IRELAND LIMITED
attorney:                                      by its duly appointed attorney:


By /s/ Terrence L. Dugan                       By /s/ Terrence L. Dugan
   ------------------------------------            -----------------------------
   Name: Terrence L. Dugan                        Name: Terrence L. Dugan


Witnesseth: /s/ Lindsay Stieber                Witnesseth: /s/ Lindsay Stieber
           ----------------------------                    ---------------------
    Name: Lindsay Stieber                          Name: Lindsay Stieber


SIGNED, SEALED and DELIVERED by GLOBAL         SIGNED, SEALED and DELIVERED by
CROSSING SERVICES EUROPE LIMITED by its        GLOBAL CROSSING SERVICES IRELAND
duly appointed attorney:                       LIMITED by its duly appointed
                                               attorney:


By /s/ Terrence L. Dugan                       By /s/ Terrence L. Dugan
   ------------------------------------           ------------------------------
   Name: Terrence L. Dugan                        Name: Terrence L. Dugan


Witnesseth: /s/ Lindsay Stieber                Witnesseth: /s/ Lindsay Stieber
            ---------------------------                    ---------------------
    Name: Lindsay Stieber                          Name: Lindsay Stieber

                            Global Security Agreement

<PAGE>

                                       28

EUROPEAN GUARANTORS

GC HUNGARY HOLDINGS                            GC LANDING CO. GMBH
   VAGYONKEZELO KORLATOLT
   FELELOSSEGU TARSASAG


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GC PAN EUROPEAN CROSSING                       GC PAN EUROPEAN CROSSING
   BELGIE B.V.B.A.                                DANMARK A.P.S.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GC PAN EUROPEAN CROSSING                       GC PAN EUROPEAN CROSSING
   DEUTSCHLAND GMBH                               FRANCE S.A.R.L.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GC PAN EUROPEAN CROSSING                       GC PAN EUROPEAN CROSSING
   HOLDINGS B.V.                                  ITALIA S.R.L.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: ATTORNEY-IN-FACT BY
                                               VIRTUE OF THE POWER OF ATTORNEY
                                               EXECUTED ON NOVEMBER 6 2003
                                               BEFORE NOTARY MARIA CELESTE
                                               PAMPURI NOTARY PUBLIC IN MILAN


GC PAN EUROPEAN CROSSING                       GC PAN EUROPEAN CROSSING
   LUXEMBOURG I S.A.R.L.                          LUXEMBOURG II S.A.R.L.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       29

GC PAN EUROPEAN CROSSING                       GC PAN EUROPEAN CROSSING
   NEDERLAND B.V.                                 NETWORKS B.V.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GC PAN EUROPEAN CROSSING                       GC PAN EUROPEAN CROSSING
   NORGE AS                                       SVERIGE AB


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GC PAN EUROPEAN CROSSING                       GLOBAL CROSSING BELGIE
   SWITZERLAND GMBH                               B.V.B.A.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GLOBAL CROSSING CYPRUS HOLDINGS LIMITED        GLOBAL CROSSING DANMARK APS


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GLOBAL CROSSING DEUTSCHLAND GMBH               GLOBAL CROSSING FRANCE SAS


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       30

GLOBAL CROSSING ITALIA S.R.L.                  GLOBAL CROSSING NEDERLAND B.V.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: ATTORNEY-IN-FACT BY VIRTUE              Title: Attorney-in-fact
OF THE POWER OF ATTORNEY EXECUTED ON
NOVEMBER 6 2003 BEFORE NOTARY MARIA
CELESTE PAMPURI NOTARY PUBLIC IN MILAN


GLOBAL CROSSING NORGE AS                       GLOBAL CROSSING SVERIGE AB


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GLOBAL CROSSING SWITZERLAND GMBH               GLOBAL CROSSING VENEZUELA B.V.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GT NETHERLANDS B.V.                            INTERNATIONAL EXCHANGE
                                                  NETWORKS SAS


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       31

GLOBAL MARINE GUARANTORS:

GLOBAL MARINE CABLE SYSTEMS                    GLOBAL MARINE SYSTEMS
   PTE LIMITED                                    (DEPOTS) LIMITED


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Authorized Signatory


                                               Executed as a deed by
GLOBAL MARINE SYSTEMS (JAPAN) LIMITED          GLOBAL MARINE SYSTEMS LIMITED


By /s/ David Sheffey                           By /s/ Terrence L. Dugan
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: Terrence L. Dugan
   Title: Attorney-in-fact                        Title: Attorney-in-fact


                                               By /s/ David Sheffey
                                                  ------------------------------
                                                  Name: David Sheffey
                                                  Title: Attorney-in-fact


VIBRO EINSPULTECHNIK
   DUKER- UND WASSERBAU GMBH


By /s/ David Sheffey
   ------------------------------------
   Name: David Sheffey
   Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       32

CARIBBEAN AND LATIN AMERICAN GUARANTORS:


GC ST. CROIX COMPANY, INC.                     GLOBAL CROSSING MEXICANA S.
                                                  DE R.L. DE C.V.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


GLOBAL CROSSING PANAMA INC.                    GC SAC ARGENTINA S.R.L.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


SAC BRASIL HOLDING LTDA.                       SAC BRASIL LTDA.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


SAC CHILE S.A.                                 SAC COLOMBIA LIMITADA


By                                             By
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact


SAC PANAMA S.A.                                SAC PERU S.R.L.


By /s/ David Sheffey                           By /s/ David Sheffey
   ------------------------------------           ------------------------------
   Name: David Sheffey                            Name: David Sheffey
   Title: Attorney-in-fact                        Title: Attorney-in-fact

                            Global Security Agreement

<PAGE>

                                       33

                                               TRUSTEE

                                               WELLS FARGO BANK MINNESOTA, N.A.,
                                                  as Trustee


                                               By: /s/ Jane Y. Schweiger
                                                   -----------------------------
                                                   Name: Jane Y. Schweiger
                                                   Title: Vice President

                            Global Security Agreement