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                                                                   EXHIBIT 10.25


                         REGISTRATION RIGHTS AGREEMENT

     This Registration Rights Agreement (this "Agreement") is made and entered
into as of February 2, 2000, by and among SkyLynx Communications, Inc., a
Delaware corporation (the "Company"), and each of the Purchasers listed on the
signature pages hereto (collectively, the "Purchasers").

     This Agreement is being entered into pursuant to the Series F Convertible
Preferred Stock Purchase Agreement, dated as of the date hereof, by and among
the Company and the Purchasers (the "Purchase Agreement").

     The Company and the Purchasers hereby agree as follows:

     1.   Definitions.
          -----------

     Capitalized terms used and not otherwise defined herein shall have the
meanings given such terms in the Purchase Agreement.  As used in this Agreement,
the following terms shall have the following meanings:

     "Advice" shall have the meaning set forth in Section 3(m).

     "Affiliate" means, with respect to any Person, any other Person that
directly or indirectly controls or is controlled by or under common control with
such Person.  For the purposes of this definition, "control," when used with
respect to any Person, means the possession, direct or indirect, of the power to
direct or cause the direction of the management and policies of such Person,
whether through the ownership of voting securities, by contract or otherwise;
and the terms of "affiliated," "controlling" and "controlled" have meanings
correlative to the foregoing.

     "Blackout Period" shall have the meaning set forth in Section 3(n).

     "Board" shall have the meaning set forth in Section 3(n).

     "Business Day" means any day except Saturday, Sunday and any day which
shall be a legal holiday or a day on which banking institutions in the state of
New York generally are authorized or required by law or other government actions
to close.

     "Closing Date" means the date of the last closing of the sale of Preferred
Stock pursuant to the Purchase Agreement.

     "Commission" means the Securities and Exchange Commission.

     "Common Stock" means the Company's Common Stock, par value $0.001 per
share.

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     "Effectiveness Date" means with respect to the Registration Statement the
120/th/ day following the First Closing Date.

     "Effectiveness Period" shall have the meaning set forth in Section 2.

     "Event" shall have the meaning set forth in Section 7(e).

     "Exchange Act" means the Securities Exchange Act of 1934, as amended.

     "Filing Date" means the 60/th/ day following the First Closing Date.

     "Holders" means the holders from time to time of Registrable Securities.

     "Indemnified Party" shall have the meaning set forth in Section 5(c).

     "Indemnifying Party" shall have the meaning set forth in Section 5(c).

     "Losses" shall have the meaning set forth in Section 5(a).

     "OTC Bulletin Board" shall mean the over-the-counter electronic bulletin
board.

     "Periodic Amount" shall have the meaning set forth in Section 7(e).

     "Person" means an individual or a corporation, partnership, trust,
incorporated or unincorporated association, joint venture, limited liability
company, joint stock company, government (or an agency or political subdivision
thereof) or other entity of any kind.

     "Preferred Stock" means the Series F Convertible Preferred Stock, par value
$.01 per share and stated value $1,000 per share, of the Company issued to the
Purchasers pursuant to the Purchase Agreement.

     "Proceeding" means an action, claim, suit, investigation or proceeding
(including, without limitation, an investigation or partial proceeding, such as
a deposition), whether commenced or threatened.

     "Prospectus" means the prospectus included in the Registration Statement
(including, without limitation, a prospectus that includes any information
previously omitted from a prospectus filed as part of an effective registration
statement in reliance upon Rule 430A promulgated under the Securities Act), as
amended or supplemented by any prospectus supplement, with respect to the terms
of the offering of any portion of the Registrable Securities covered by the
Registration Statement, and all other amendments and supplements to the
Prospectus, including post-effective amendments, and all material incorporated
by reference in such Prospectus.

     "Registrable Securities" means (i) the shares of Common Stock issuable upon
conversion of the Preferred Stock (the "Conversion Shares"), and upon any stock
split, stock dividend, recapitalization or similar event with respect to such
Conversion Shares and (ii) any other dividend or other distribution with respect
to, conversion or exchange of, or in replacement of,

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Registrable Securities; provided, however, that Registrable Securities shall
include (but not be limited to) a number of shares of Common Stock equal to no
less than 100% of the maximum number of shares of Common Stock issuable upon
conversion of the Preferred Stock sold on or prior to the Closing Date.
Notwithstanding anything contained herein to the contrary, if the actual number
of shares of Common Stock issuable upon conversion of the Preferred Stock
exceeds 100% of the number of shares of Common Stock issuable upon conversion of
the Preferred Stock sold on or prior to the Closing Date, the term "Registrable
Securities" shall be deemed to include such additional shares of Common Stock.

     "Registration Statement" means a registration statement and any additional
registration statement contemplated by Section 2, including (in each case) the
Prospectus, amendments and supplements to such registration statement or
Prospectus, including pre- and post-effective amendments, all exhibits thereto,
and all material incorporated by reference in such registration statement.

     "Rule 144" means Rule 144 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

     "Rule 158" means Rule 158 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

     "Rule 415" means Rule 415 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

     "Securities Act" means the Securities Act of 1933, as amended.

     "Special Counsel" means Parker Chapin Flattau & Klimpl, LLP (unless such
counsel no longer represents any of the Holders), for which the Holders will be
reimbursed by the Company pursuant to Section 4.

     2.   Shelf Registration.
          ------------------

     On or prior to the Filing Date, the Company shall prepare and file with the
Commission a "shelf" Registration Statement covering all Registrable Securities
for an offering to be made on a continuous basis pursuant to Rule 415. The
Registration Statement shall be on Form S-3 (except if the Company is not then
eligible to register for resale the Registrable Securities on Form S-3, in which
case such registration shall be on another appropriate form in accordance
herewith). The Company shall (i) not permit any securities other than the
Registrable Securities to be included in the Registration Statement and (ii) use
its best efforts to cause the Registration Statement to be declared effective
under the Securities Act as promptly as possible after filing thereof, but in
any event prior to the Effectiveness Date and to keep such Registration
Statement continuously effective under the Securities Act until such date as is
the earlier of (x) the date when all Registrable Securities covered by such
Registration Statement have been sold or (y) the date on which the Registrable
Securities may be sold without any restriction, and are freely tradeable without
legends, pursuant to Rule 144(k), as determined by the counsel to the

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Company pursuant to a written opinion letter addressed to the Company's transfer
agent to such effect (unless counsel to such Purchaser reasonably concludes that
sales of such Registrable Securities by such Purchaser remain subject to any
restriction, or that the legends may not be removed from the Registrable
Securities, under Rule 144(k)) (the "Effectiveness Period"). If an additional
Registration Statement is required to be filed because the actual number of
shares of Common Stock into which the Preferred Stock is convertible exceeds the
number of shares of Common Stock initially registered in respect of the
Conversion Shares, the Company shall have thirty (30) days to file such
additional Registration Statement, and the Company shall use its best efforts to
cause such additional Registration Statement to be declared effective by the
Commission as soon as possible, but in no event later than sixty (60) days after
filing.

     3.   Registration Procedures.
          -----------------------

     In connection with the Company's registration obligations hereunder, the
Company shall:

          (a)  Prepare and file with the Commission, on or prior to the Filing
Date, a Registration Statement on Form S-3 (or, if the Company is not then
eligible to register for resale the Registrable Securities on Form S-3, such
registration shall be on another appropriate form in accordance herewith) in
accordance with the method or methods of distribution thereof as specified by
the Holders, and shall use its best efforts to cause the Registration Statement
to become effective and remain effective as provided herein; provided, however,
that not less than five (5) Business Days prior to the filing of the
Registration Statement or any related Prospectus or any amendment or supplement
thereto (including any document that would be incorporated therein by
reference), the Company shall (i) furnish to the Holders and their Special
Counsel copies of all such documents proposed to be filed, which documents
(other than those incorporated by reference) will be subject to the review of
the Holders and their Special Counsel, and (ii) at the request of the Holders,
cause its officers and directors, counsel and independent certified public
accountants to respond to such inquiries as shall be necessary, in the
reasonable opinion of their Special Counsel to the Holders, to conduct a
reasonable investigation within the meaning of the Securities Act.

          The Company shall not file the Registration Statement or any
Prospectus or any amendments or supplements thereto to which the Holders of a
majority of the Registrable Securities or their Special Counsel shall reasonably
object to in writing within three (3) Business Days of their receipt thereof if
such filing may contain information that may result in a misstatement of fact or
an omission of a material fact.

          (b)  (i) Prepare and file with the Commission such amendments,
including post-effective amendments, to the Registration Statement as may be
necessary to keep the Registration Statement continuously effective as to the
applicable Registrable Securities for the Effectiveness Period and prepare and
file with the Commission such additional Registration Statements in order to
register for resale under the Securities Act all of the Registrable Securities;
(ii) cause the related Prospectus to be amended or supplemented by any required
Prospectus supplement, and as so supplemented or amended to be filed pursuant to
Rule 424 (or any similar provisions then in force) promulgated under the
Securities Act; (iii) respond as promptly as practicable to any comments
received from the Commission with respect to the Registration Statement or any
amendment thereto and as promptly as practicable provide the

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Holders true and complete copies of all correspondence from and to the
Commission relating to the Registration Statement; and (iv) comply in all
material respects with the provisions of the Securities Act and the Exchange Act
with respect to the disposition of all Registrable Securities covered by the
Registration Statement during the applicable period in accordance with the
intended methods of disposition by the Holders thereof set forth in the
Registration Statement as so amended or in such Prospectus as so supplemented.

          (c)  Notify the Holders and their Special Counsel in writing as
promptly as possible (and, in the case of (i)(A) below, not less than five (5)
Business Days prior to such filing) and (if requested by any such Person)
confirm such notice in writing no later than one (1) Business Day following the
day: (i)(A) when a Prospectus or any Prospectus supplement or post-effective
amendment to the Registration Statement is proposed to be filed; (B) when the
Commission notifies the Company whether there will be a "review" of such
Registration Statement and whenever the Commission comments in writing on such
Registration Statement and (C) with respect to the Registration Statement or any
post-effective amendment, when the same has become effective; (ii) of any
request by the Commission or any other Federal or state governmental authority
for amendments or supplements to the Registration Statement or Prospectus or for
additional information; (iii) of the issuance by the Commission of any stop
order suspending the effectiveness of the Registration Statement covering any or
all of the Registrable Securities or the initiation of any Proceedings for that
purpose; (iv) if at any time any of the representations and warranties of the
Company contained in any agreement contemplated hereby ceases to be true and
correct in all material respects; (v) of the receipt by the Company of any
notification with respect to the suspension of the qualification or exemption
from qualification of any of the Registrable Securities for sale in any
jurisdiction, or the initiation or threatening of any Proceeding for such
purpose; and (vi) of the occurrence of any event that makes any statement made
in the Registration Statement or Prospectus or any document incorporated or
deemed to be incorporated therein by reference untrue in any material respect or
that requires any revisions to the Registration Statement, Prospectus or other
documents so that, in the case of the Registration Statement or the Prospectus,
as the case may be, it will not contain any untrue statement of a material fact
or omit to state any material fact required to be stated therein or necessary to
make the statements therein, in the light of the circumstances under which they
were made, not misleading.

          (d)  Use its best efforts to avoid the issuance of, or, if issued,
obtain the withdrawal of, (i) any order suspending the effectiveness of the
Registration Statement or (ii) any suspension of the qualification (or exemption
from qualification) of any of the Registrable Securities for sale in any
jurisdiction, at the earliest practicable moment.

          (e)  If requested by the Holders of a majority in interest of the
Registrable Securities, (i) promptly incorporate in a Prospectus supplement or
post-effective amendment to the Registration Statement such information as the
Company reasonably agrees should be included therein and (ii) make all required
filings of such Prospectus supplement or such post-effective amendment as soon
as practicable after the Company has received notification of the matters to be
incorporated in such Prospectus supplement or post-effective amendment.

          (f)  Furnish to any Holders and their Special Counsel, without charge,
one conformed copy of each Registration Statement and each amendment thereto,
including financial

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statements and schedules, all documents incorporated or deemed to be
incorporated therein by reference, and all exhibits to the extent requested by
any Holders or their Special Counsel (including those previously furnished or
incorporated by reference) promptly after the filing of such documents with the
Commission.

          (g)  Promptly deliver to any Holders and their Special Counsel,
without charge, as many copies of the Prospectus or Prospectuses (including each
form of prospectus) and each amendment or supplement thereto as such Holders or
their Special Counsel may reasonably request; and the Company hereby consents to
the use of such Prospectus and each amendment or supplement thereto by each of
the Holders in connection with the offering and sale of the Registrable
Securities covered by such Prospectus and any amendment or supplement thereto.

          (h)  Prior to any public offering of Registrable Securities, use its
best efforts to register or qualify or cooperate with the Holders and their
Special Counsel in connection with the registration or qualification (or
exemption from such registration or qualification) of such Registrable
Securities for offer and sale under the securities or Blue Sky laws of such
jurisdictions within the United States as the Holders request in writing, to
keep each such registration or qualification (or exemption therefrom) effective
during the Effectiveness Period and to do any and all other acts or things
necessary or advisable to enable the disposition in such jurisdictions of the
Registrable Securities covered by a Registration Statement; provided, however,
that the Company shall not be required to qualify generally to do business in
any jurisdiction where it is not then so qualified or to take any action that
would subject it to general service of process in any such jurisdiction where it
is not then so subject or subject the Company to any material tax in any such
jurisdiction where it is not then so subject.

          (i)  Cooperate with the Holders to facilitate the timely preparation
and delivery of certificates representing Registrable Securities to be sold
pursuant to a Registration Statement, which certificates shall be free of all
restrictive legends, and to enable such Registrable Securities to be in such
denominations and registered in such names as any Holder may request at least
two (2) Business Days prior to any sale of Registrable Securities.

          (j)  Upon the occurrence of any event contemplated by Section
3(c)(vi), as promptly as possible, prepare a supplement or amendment, including
a post-effective amendment, to the Registration Statement or a supplement to the
related Prospectus or any document incorporated or deemed to be incorporated
therein by reference, and file any other required document so that, as
thereafter delivered, neither the Registration Statement nor such Prospectus
will contain an untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein,
in the light of the circumstances under which they were made, not misleading.

          (k)  Use its best efforts to cause all Registrable Securities relating
to such Registration Statement to be listed on the OTC Bulletin Board and any
other securities exchange, quotation system, market or over-the-counter bulletin
board, if any, on which similar securities issued by the Company are then listed
as and when required pursuant to the Purchase Agreement.

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          (l)  Comply in all material respects with all applicable rules and
regulations of the Commission and make generally available to its security
holders earning statements satisfying the provisions of Section 11(a) of the
Securities Act and Rule 158 not later than 90 days after the end of any 12-month
period (or within such extended period of time as may be permitted by the
Commission for filing the applicable report with the Commission) commencing on
the first day of the first fiscal quarter of the Company after the effective
date of the Registration Statement, which statement shall conform to the
requirements of Rule 158.

          (m)  The Company may require each selling Holder to furnish to the
Company information regarding such Holder and the distribution of such
Registrable Securities as is required by law to be disclosed in the Registration
Statement, and the Company may exclude from registration the Registrable
Securities of any such Holder who unreasonably fails to furnish such information
within a reasonable time after receiving such request.

          If the Registration Statement refers to any Holder by name or
otherwise as the holder of any securities of the Company, then such Holder shall
have the right to require (if such reference to such Holder by name or otherwise
is not required by the Securities Act or any similar federal statute then in
force) the deletion of the reference to such Holder in any amendment or
supplement to the Registration Statement filed or prepared subsequent to the
time that such reference ceases to be required.

          Each Holder covenants and agrees that (i) it will not sell any
Registrable Securities under the Registration Statement until it has received
copies of the Prospectus as then amended or supplemented as contemplated in
Section 3(g) and notice from the Company that such Registration Statement and
any post-effective amendments thereto have become effective as contemplated by
Section 3(c) and (ii) it and its officers, directors or Affiliates, if any, will
comply with the prospectus delivery requirements of the Securities Act as
applicable to them in connection with sales of Registrable Securities pursuant
to the Registration Statement.

          Each Holder agrees by its acquisition of such Registrable Securities
that, upon receipt of a notice from the Company of the occurrence of any event
of the kind described in Section 3(c)(ii), 3(c)(iii), 3(c)(iv), 3(c)(v) or
3(c)(vi), such Holder will forthwith discontinue disposition of such Registrable
Securities under the Registration Statement until such Holder's receipt of the
copies of the supplemented Prospectus and/or amended Registration Statement
contemplated by Section 3(j), or until it is advised in writing (the "Advice")
by the Company that the use of the applicable Prospectus may be resumed, and, in
either case, has received copies of any additional or supplemental filings that
are incorporated or deemed to be incorporated by reference in such Prospectus or
Registration Statement.

          (n)  If (i) there is material non-public information regarding the
Company which the Company's Board of Directors (the "Board") reasonably
determines not to be in the Company's best interest to disclose and which the
Company is not otherwise required to disclose, or (ii) there is a significant
business opportunity (including, but not limited to, the acquisition or
disposition of assets (other than in the ordinary course of business) or any
merger, consolidation, tender offer or other similar transaction) available to
the Company which the Board reasonably determines not to be in the Company's
best interest to disclose and which the Company would be required to disclose
under the Registration Statement, then the Company may postpone or suspend

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filing or effectiveness of a Registration Statement for a period not to exceed
twenty (20) consecutive days, provided that the Company may not postpone or
suspend its obligation under this Section 3(n) for more than forty-five (45)
days in the aggregate during any 12-month period (each, a "Blackout Period");
provided, however, that no such postponement or suspension shall be permitted
for consecutive 20-day periods, arising out of the same set of facts,
circumstances or transactions.

     4.   Registration Expenses.
          ---------------------

     All fees and expenses incident to the performance of or compliance with
this Agreement by the Company shall be borne by the Company whether or not the
Registration Statement is filed or becomes effective and whether or not any
Registrable Securities are sold pursuant to the Registration Statement. The fees
and expenses referred to in the foregoing sentence shall include, without
limitation: (i) all registration and filing fees (including, without limitation,
fees and expenses (A) with respect to filings required to be made with the OTC
Bulletin Board and each other securities exchange or market on which Registrable
Securities are required hereunder to be listed, (B) with respect to filings
required to be made with the Commission, (C) with respect to filings required to
be made under the OTC Bulletin Board and (D) in compliance with state securities
or Blue Sky laws (including, without limitation, fees and disbursements of
Special Counsel to the Holders in connection with Blue Sky qualifications of the
Registrable Securities and determination of the eligibility of the Registrable
Securities for investment under the laws of such jurisdictions), (ii) printing
expenses (including, without limitation, expenses of printing certificates for
Registrable Securities and of printing prospectuses), (iii) messenger, telephone
and delivery expenses, (iv) fees and disbursements of counsel for the Company
and the Special Counsel for the Holders, in the case of the Special Counsel, up
to a maximum of $10,000, (v) Securities Act liability insurance, if the Company
so desires such insurance, and (vi) fees and expenses of all other Persons
retained by the Company in connection with the consummation of the transactions
contemplated by this Agreement, including, without limitation, the Company's
independent public accountants (including the expenses of any comfort letters or
costs associated with the delivery by independent public accountants of a
comfort letter or comfort letters). In addition, the Company shall be
responsible for all of its internal expenses incurred in connection with the
consummation of the transactions contemplated by this Agreement (including,
without limitation, all salaries and expenses of its officers and employees
performing legal or accounting duties), the expense of any annual audit, the
fees and expenses incurred in connection with the listing or relisting of the
Registrable Securities on the OTC Bulletin Board or any securities exchange as
required hereunder.

     5.   Indemnification.
          ---------------

          (a)  Indemnification by the Company.  The Company shall,
notwithstanding any termination of this Agreement, indemnify and hold harmless
each Holder, the officers, directors, agents, brokers (including brokers who
offer and sell Registrable Securities as principal as a result of a pledge or
any failure to perform under a margin call of Common Stock), investment advisors
and employees of each of them, each Person who controls such Holder (within the
meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act)
and the officers, directors, agents, investment advisors and employees of each
such controlling Person, to the fullest extent permitted by applicable law, from
and against any and all losses,

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claims, damages, liabilities, costs (including, without limitation, costs of
preparation and attorneys' fees) and expenses (collectively, "Losses"), as
incurred, arising out of or relating to any untrue or alleged untrue statement
of a material fact contained in the Registration Statement, any Prospectus or
any form of prospectus or in any amendment or supplement thereto or in any
preliminary prospectus, or arising out of or relating to any omission or alleged
omission of a material fact required to be stated therein or necessary to make
the statements therein (in the case of any Prospectus or form of prospectus or
supplement thereto, in the light of the circumstances under which they were
made) not misleading, except to the extent, but only to the extent, that such
untrue statements or omissions are based solely upon information regarding such
Holder furnished in writing to the Company by such Holder expressly for use
therein, which information was reasonably relied on by the Company for use
therein or to the extent that such information relates to such Holder or such
Holder's proposed method of distribution of Registrable Securities and was
reviewed and expressly approved in writing by such Holder expressly for use in
the Registration Statement, such Prospectus or such form of prospectus or in any
amendment or supplement thereto. The Company shall notify the Holders promptly
of the institution, threat or assertion of any Proceeding of which the Company
is aware in connection with the transactions contemplated by this Agreement.
Such indemnity shall remain in full force and effect regardless of any
investigation made by or on behalf of an Indemnified Party and shall survive the
transfer of the Registrable Securities by the Holders.

          (b)  Indemnification by Holders.  The Holders shall, severally and not
jointly, indemnify and hold harmless the Company, the directors, officers,
agents and employees, each Person who controls the Company (within the meaning
of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the
directors, officers, agents or employees of such controlling Persons, to the
fullest extent permitted by applicable law, from and against all Losses, as
incurred, arising solely out of or based solely upon any untrue statement of a
material fact contained in the Registration Statement, any Prospectus, or any
form of prospectus or in any amendment or supplement thereto or in any
preliminary prospectus, or arising solely out of or based solely upon any
omission of a material fact required to be stated therein or necessary to make
the statements therein (in the case of any Prospectus or form of prospectus or
supplement thereto, in the light of the circumstances under which they were
made) not misleading, to the extent, but only to the extent, that such untrue
statement or omission is contained in any information so furnished in writing by
such Holder to the Company specifically for inclusion in therein and that such
information was reasonably relied on by the Company for use therein or to the
extent that such information relates to such Holder or such Holder's proposed
method of distribution of Registrable Securities and was reviewed and expressly
approved in writing by such Holder expressly for use in the Registration
Statement, such Prospectus or such form of prospectus or in any amendment or
supplement thereto.  Notwithstanding anything to the contrary contained herein,
the Holder shall be liable under this Section 5(b) for only that amount as does
not exceed the net proceeds to such Holder as a result of the sale of
Registrable Securities pursuant to such Registration Statement.

          (c)  Conduct of Indemnification Proceedings.  If any Proceeding shall
be brought or asserted against any Person entitled to indemnity hereunder (an
"Indemnified Party"), such Indemnified Party promptly shall notify the Person
from whom indemnity is sought (the "Indemnifying Party) in writing, and the
Indemnifying Party shall assume the defense thereof, including the employment of
counsel reasonably satisfactory to the Indemnified Party and the

                                       9
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payment of all fees and expenses incurred in connection with defense thereof;
provided, that the failure of any Indemnified Party to give such notice shall
not relieve the Indemnifying Party of its obligations or liabilities pursuant to
this Agreement, except (and only) to the extent that it shall be finally
determined by a court of competent jurisdiction (which determination is not
subject to appeal or further review) that such failure shall have proximately
and materially adversely prejudiced the Indemnifying Party.

          An Indemnified Party shall have the right to employ separate counsel
in any such Proceeding and to participate in the defense thereof, but the fees
and expenses of such counsel shall be at the expense of such Indemnified Party
or Parties unless:  (1) the Indemnifying Party has agreed in writing to pay such
fees and expenses; or (2) the Indemnifying Party shall have failed promptly to
assume the defense of such Proceeding and to employ counsel reasonably
satisfactory to such Indemnified Party in any such Proceeding; or (3) the named
parties to any such Proceeding (including any impleaded parties) include both
such Indemnified Party and the Indemnifying Party, and such Indemnified Party
shall have been advised by counsel that a conflict of interest is likely to
exist if the same counsel were to represent such Indemnified Party and the
Indemnifying Party (in which case, if such Indemnified Party notifies the
Indemnifying Party in writing that it elects to employ separate counsel at the
expense of the Indemnifying Party, the Indemnifying Party shall not have the
right to assume the defense thereof and such counsel shall be at the expense of
the Indemnifying Party).  The Indemnifying Party shall not be liable for any
settlement of any such Proceeding effected without its written consent, which
consent shall not be unreasonably withheld.  No Indemnifying Party shall,
without the prior written consent of the Indemnified Party, effect any
settlement of any pending Proceeding in respect of which any Indemnified Party
is a party, unless such settlement includes an unconditional release of such
Indemnified Party from all liability on claims that are the subject matter of
such Proceeding.

          All fees and expenses of the Indemnified Party (including reasonable
fees and expenses to the extent incurred in connection with investigating or
preparing to defend such Proceeding in a manner not inconsistent with this
Section) shall be paid to the Indemnified Party, as incurred, within ten (10)
Business Days of written notice thereof to the Indemnifying Party (regardless of
whether it is ultimately determined that an Indemnified Party is not entitled to
indemnification hereunder; provided, that the Indemnifying Party may require
such Indemnified Party to undertake to reimburse all such fees and expenses to
the extent it is finally judicially determined that such Indemnified Party is
not entitled to indemnification hereunder).

          (d)  Contribution.  If a claim for indemnification under Section 5(a)
or 5(b) is unavailable to an Indemnified Party because of a failure or refusal
of a governmental authority to enforce such indemnification in accordance with
its terms (by reason of public policy or otherwise), then each Indemnifying
Party, in lieu of indemnifying such Indemnified Party, shall contribute to the
amount paid or payable by such Indemnified Party as a result of such Losses, in
such proportion as is appropriate to reflect the relative fault of the
Indemnifying Party and Indemnified Party in connection with the actions,
statements or omissions that resulted in such Losses as well as any other
relevant equitable considerations.  The relative fault of such Indemnifying
Party and Indemnified Party 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 of a material fact,
has been taken or made by, or

                                       10
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relates to information supplied by, such Indemnifying, Party or Indemnified
Party, and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such action, statement or omission. The amount
paid or payable by a party as a result of any Losses shall be deemed to include,
subject to the limitations set forth in Section 5(c), any reasonable attorneys'
or other reasonable fees or expenses incurred by such party in connection with
any Proceeding to the extent such party would have been indemnified for such
fees or expenses if the indemnification provided for in this Section was
available to such party in accordance with its terms. Notwithstanding anything
to the contrary contained herein, such Holder shall be liable or required to
contribute under this Section 5(c) for only that amount as does not exceed the
net proceeds to such Holder as a result of the sale of Registrable Securities
pursuant to such Registration Statement.

          The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 5(d) were determined by pro rata
allocation or by any other method of allocation that does not take into account
the equitable considerations referred to in the immediately preceding paragraph.
No Person guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the Securities Act) shall be entitled to contribution from any Person
who was not guilty of such fraudulent misrepresentation.

          The indemnity and contribution agreements contained in this Section
are in addition to any liability that the Indemnifying Parties may have to the
Indemnified Parties.

     6.   Rule 144 and Piggyback Registration.
          -----------------------------------

     (a)  As long as any Holder owns Preferred Stock or Conversion Securities,
the Company covenants to timely file (or obtain extensions in respect thereof
and file within the applicable grace period) all reports required to be filed by
the Company after the date hereof pursuant to Section 13(a) or 15(d) of the
Exchange Act and to promptly furnish the Holders with true and complete copies
of all such filings.  As long as any Holder owns Preferred Stock or Conversion
Shares, if the Company is not required to file reports pursuant to Section 13(a)
or 15(d) of the Exchange Act, it will prepare and furnish to the Holders and
make publicly available in accordance with Rule 144(c) promulgated under the
Securities Act annual and quarterly financial statements, together with a
discussion and analysis of such financial statements in form and substance
substantially similar to those that would otherwise be required to be included
in reports required by Section 13(a) or 15(d) of the Exchange Act, as well as
any other information required thereby, in the time period that such filings
would have been required to have been made under the Exchange Act.  The Company
further covenants that it will take such further action as any Holder may
reasonably request, all to the extent required from time to time to enable such
Person to sell Conversion Shares without registration under the Securities Act
within the limitation of the exemptions provided by Rule 144 promulgated under
the Securities Act.  Upon the request of any Holder, the Company shall deliver
to such Holder a written certification of a duly authorized officer as to
whether it has complied with such requirements.

     (b)  If at any time when there is not an effective Registration Statement
covering Conversion Shares, the Company shall determine to prepare and file with
the Commission a registration statement relating to an offering for its own
account or the account of others under the Securities Act of any of its equity
securities, other than: (1) on Form S-4 or Form S-8 (each

                                       11
<PAGE>

as promulgated under the Securities Act) or its then equivalents relating to
equity securities to be issued solely in connection with any acquisition of any
entity or business or equity securities issuable in connection with stock option
or other employee benefit plans; or (2) the Company's amendment or successor
registration statement to the Company's Registration Statement on Form SB-2
Registration No. 333-83705 to be filed in connection with the reincorporation of
the Company in the State of Delaware, the Company shall send to each Holder of
Registrable Securities written notice of such determination and the Company will
cause the registration under the Securities Act of all Registrable Securities
(unless within thirty (30) days after receipt of such notice, any such Holder
shall notify the Company in writing that it elects to have less than all of its
Registrable Securities intended to be disposed of by such Holder included in
such registration) to the extent requisite to permit the disposition of the
Registrable Securities so to be registered, provided that if at any time after
giving written notice of its intention to register any securities and prior to
the effective date of the registration statement filed in connection with such
registration, the Company shall determine for any reason not to register or to
delay registration of such securities, the Company may, at its election, give
written notice of such determination to such Holder and, thereupon, (i) in the
case of a determination not to register, shall be relieved of its obligation to
register any Registrable Securities in connection with such registration (but
not from its obligation to pay expenses in accordance with Section 4 hereof),
and (ii) in the case of a determination to delay registering, shall be permitted
to delay registering any Registrable Securities being registered pursuant to
this Section 6(b) for the same period as the delay in registering such other
securities. The Company shall include in such registration statement all or any
part of such Registrable Securities such Holder requests to be registered;
provided, however, that the Company shall not be required to register any
Registrable Securities pursuant to this Section 6(b) that are eligible for sale
pursuant to Rule 144(k) of the Securities Act. In the case of an underwritten
public offering, if the managing underwriter(s) or underwriter(s) should
reasonably object to the inclusion of the Registrable Securities in such
registration statement, then if the Company after consultation with the managing
underwriter should reasonably determine that the inclusion of such Registrable
Securities would materially adversely affect the offering contemplated in such
registration statement, and based on such determination recommends inclusion in
such registration statement of fewer or none of the Registrable Securities of
the Holders, then (x) the number of Registrable Securities of the Holders
included in such registration statement shall be reduced pro-rata among such
Holders (based upon the number of Registrable Securities requested to be
included in the registration), if the Company after consultation with the
underwriter(s) recommends the inclusion of fewer Registrable Securities, or (y)
none of the Registrable Securities of the Holders shall be included in such
registration statement, if the Company after consultation with the
underwriter(s) recommends the inclusion of none of such Registrable Securities;
provided, however, that if securities are being offered for the account of other
persons or entities as well as the Company, such reduction shall not represent a
greater fraction of the number of Registrable Securities intended to be offered
by the Holders than the fraction of similar reductions imposed on such other
persons or entities (other than the Company).

     7.   Miscellaneous.
          -------------

          (a)  Remedies. In the event of a breach by the Company, on the one
hand, or by a Holder, on the other hand, of any of their respective obligations
under this Agreement, each Holder or the Company, as the case may be, in
addition to being entitled to exercise all rights

                                       12
<PAGE>

granted by law and under this Agreement, including recovery of damages, will be
entitled to specific performance of its respective rights under this Agreement.
The Company and the Holders agree that monetary damages would not provide
adequate compensation for any losses incurred by reason of a breach by it of any
of the provisions of this Agreement and hereby further agree that, in the event
of any action for specific performance in respect of such breach, it shall waive
the defense that a remedy at law would be adequate.

          (b)  No Inconsistent Agreements.  Except as set forth in the
Registration Rights Agreement, dated as of January 18, 1999, by and among the
Company and purchasers of its Series B Convertible Preferred Stock, the
Registration Rights Agreement, dated as of April 16, 1999, by and among the
Company and purchasers of its Series D Convertible Preferred Stock, and the
Registration Rights Agreement, dated as of May 6, 1999, by and among the Company
and purchasers of its Series E Convertible Preferred Stock (the "Prior
Registration Rights Agreements"), neither the Company nor any of its
subsidiaries is, as of the date hereof, a party to, nor shall the Company or any
of its subsidiaries, on or after the date of this Agreement, enter into, any
agreement with respect to its securities that is inconsistent with the rights
granted to the Holders in this Agreement or otherwise conflicts with the
provisions hereof.  Without limiting the generality of the foregoing, without
the written consent of the Holders of at least three-quarters of the then
outstanding Registrable Securities, the Company shall not grant to any Person
the right to request the Company to register any securities of the Company under
the Securities Act unless the rights so granted are not prior to and are not
otherwise in conflict with the provisions of this Agreement.

          (c)  No Piggyback on Registrations.  Except as set forth in the Prior
Registration Rights Agreements, neither the Company nor any of its security
holders (other than the Holders in such capacity pursuant hereto) may include
securities of the Company in the Registration Statement, and the Company shall
not after the date hereof enter into any agreement providing such right to any
of its security holders, unless the right so granted is subject in all respects
to the prior rights in full of the Holders set forth herein, and is not
otherwise in conflict with the provisions of this Agreement.

          (d)  Failure to File Registration Statement and Other Events. The
Company and the Purchasers agree that the Holders will suffer damages if the
Registration Statement is not filed on or prior to the Filing Date and not
declared effective by the Commission on or prior to the Effectiveness Date and
maintained in the manner contemplated herein during the Effectiveness Period or
if certain other events occur. The Company and the Holders further agree that it
would not be feasible to ascertain the extent of such damages with precision.
Accordingly, if (i) the Registration Statement is not filed on or prior to the
Filing Date, or is not declared effective by the Commission on or prior to the
Effectiveness Date (or in the event an additional Registration Statement to be
filed because the actual number of shares of Common Stock into which the
Preferred Stock is convertible exceeds the number of shares of Common Stock
initially registered is not filed and declared effective within the time periods
set forth in Section 2(a)), or (ii) the Company fails to file with the
Commission a request for acceleration in accordance with Rule 12d1-2 promulgated
under the Exchange Act within five (5) Business Days of the date that the
Company is notified (orally or in writing, whichever is earlier) by the
Commission that a Registration Statement will not be "reviewed," or not subject
to further review, or (iii) the Registration Statement is filed with and
declared effective by the Commission

                                       13
<PAGE>

but thereafter ceases to be effective as to all Registrable Securities at any
time prior to the expiration of the Effectiveness Period, without being
succeeded immediately by a subsequent Registration Statement filed with and
declared effective by the Commission, or (iv) trading in the Common Stock shall
be suspended or if the Common Stock is delisted from the OTC Bulletin Board for
any reason for more than ten (10) Business Days in the aggregate, or (v) the
Company breaches in a material respect (x) any covenant or other material term
or condition to this Agreement, (y) Section 5(b)(ii) or (v) or Section 5(k) of
the Certificate of Designation or (z) Section 3.2, 3.7, 3.8, 3.10, 3.11, 3.13 or
3.14 of the Purchase Agreement, and such breach continues for a period of thirty
(30) days after written notice thereof to the Company, or (vi) the Company has
breached Section 3(n) of this Agreement (any such failure or breach of this
Section 7(e)((i)-(vi) being referred to as an "Event"), the Company shall pay in
                                               -----
cash as liquidated damages for such failure and not as a penalty to each Holder
an amount equal to one percent (1%) of such Holder's pro rata share of the
purchase price paid by all Holders for all shares of the Preferred Stock
purchased and then outstanding pursuant to the Purchase Agreement for the
initial thirty (30) day period until the applicable Event has been cured, which
shall be pro rated for such periods less than thirty (30) days, and two percent
(2%) of such Holder's pro rata share for each thirty (30) day period thereafter
until the applicable Event has been cured (which shall be also pro rated, as
aforesaid) (the "Periodic Amount"). Payments to be made pursuant to this Section
                 ---------------
7(e) shall be due and payable immediately upon demand in immediately available
funds. The parties agree that the Periodic Amount represents a reasonable
estimate on the part of the parties, as of the date of this Agreement, of the
amount of damages that may be incurred by the Holders if the Registration
Statement is not filed on or prior to the Filing Date or has not been declared
effective by the Commission on or prior to the Effectiveness Date and maintained
in the manner contemplated herein during the Effectiveness Period or if any
other Event as described herein has occurred and not been cured.

          (e)  Specific Enforcement, Consent to Jurisdiction.

          (i)  The Company and the Purchasers acknowledge and agree that
irreparable damage would occur in the event that any of the provisions of this
Agreement or the Purchase Agreement were not performed in accordance with their
specific terms or were otherwise breached.  It is accordingly agreed that the
parties shall be entitled to an injunction or injunctions to prevent or cure
breaches of the provisions of this Agreement or the Purchase Agreement and to
enforce specifically the terms and provisions hereof or thereof, this being in
addition to any other remedy to which any of them may be entitled by law or
equity.

          (ii) Each of the Company and each of the Purchasers (i) hereby
irrevocably submits to the jurisdiction of the United States District Court
sitting in the State of Delaware for the purposes of any suit, action or
proceeding arising out of or relating to this Agreement or the Purchase
Agreement and (ii) hereby waives, and agrees not to assert in any such suit,
action or proceeding, any claim that it is not personally subject to the
jurisdiction of such court, that the suit, action or proceeding is brought in an
inconvenient forum or that the venue of the suit, action or proceeding is
improper. Each of the Company and each of the Purchasers consents to process
being served in any such suit, action or proceeding by mailing a copy thereof to
such party at the address in effect for notices to it under this Agreement and
agrees that such service shall constitute good and sufficient service of process
and notice thereof. Nothing in this Section 7(e) shall affect or limit any right
to serve process in any other manner permitted by law.

                                       14
<PAGE>

          (f)  Amendments and Waivers.  The provisions of this Agreement,
including the provisions of this sentence, may not be amended, modified or
supplemented, and waivers or consents to departures from the provisions hereof
may not be given, unless the same shall be in writing and signed by the Company
and each of the Holders.  Notwithstanding the foregoing, a waiver or consent to
depart from the provisions hereof with respect to a matter that relates
exclusively to the rights of Holders and that does not directly or indirectly
affect the rights of other Holders may be given by Holders of at least a
majority of the Registrable Securities to which such waiver or consent relates;
provided, however, that the provisions of this sentence may not be amended,
--------  -------
modified, or supplemented except in accordance with the provisions of the
immediately preceding sentence.

          (g)  Notices.  Any and all notices or other communications or
deliveries required or permitted to be provided hereunder shall be in writing
and shall be deemed given and effective on the earlier of (i) the date of
transmission, if such notice or communication is delivered via facsimile at the
facsimile telephone number specified for notice prior to 5:00 p.m., California
Time, on a Business Day, (ii) the Business Day after the date of transmission,
if such notice or communication is delivered via facsimile at the facsimile
telephone number specified for notice later than 5:00 p.m., California Time, on
any date and earlier than 11:59 p.m., California Time, on such date, (iii) the
Business Day following the date of mailing, if sent by nationally recognized
overnight courier service or (iv) actual receipt by the party to whom such
notice is required to be given.  The address for such communications with
respect to each of the Holders shall be that set forth under such Holder's name
on Holder's signature page hereto, or with respect to the Company, addressed to:

          SkyLynx Communications, Inc.
          600 South Cherry Street
          Suite 400
          Denver, CO 80246
          Attention: Jeffery A. Mathias, President and CEO
          Facsimile: (303) 316-0404

or to such other address or addresses or facsimile number or numbers as any such
party may most recently have designated in writing to the other parties hereto
by such notice. Copies of notices to any Holder shall be sent to the addresses
listed on Holder's signature page attached hereto, if applicable. Copies of
notices to the Holders shall be sent to Parker Chapin Flattau & Klimpl, LLP,
1211 Avenue of the Americas, New York, New York 10036, Attention: Christopher S.
Auguste, Esq., Facsimile No.: (212) 704-6288.

          (h)  Successors and Assigns.  This Agreement shall be binding upon and
inure to the benefit of the parties and their successors and permitted assigns
and shall inure to the benefit of each Holder and its successors and assigns.
The Company may not assign this Agreement or any of its rights or obligations
hereunder without the prior written consent of the Holders.  The Purchasers may
assign their rights hereunder in the manner and to the Persons as permitted
under the Purchase Agreement.

          (i)  Assignment of Registration Rights.  The rights of each Holder
hereunder, including the right to have the Company register for resale
Registrable Securities in accordance

                                       15
<PAGE>

with the terms of this Agreement, shall be automatically assignable by each
Holder to any transferee of such Holder of all or a portion of the shares of
Preferred Stock or the Registrable Securities if: (i) the Holder agrees in
writing with the transferee or assignee to assign such rights, and a copy of
such agreement is furnished to the Company within a reasonable time after such
assignment, (ii) the Company is, within a reasonable time after such transfer or
assignment, furnished with written notice of (a) the name and address of such
transferee or assignee and (b) the securities with respect to which such
registration rights are being transferred or assigned, (iii) following such
transfer or assignment the further disposition of such securities by the
transferee or assignees is restricted under the Securities Act and applicable
state securities laws, (iv) at or before the time the Company receives the
written notice contemplated by clause (ii) of this Section, the transferee or
assignee agrees in writing with the Company to be bound by all of the provisions
of this Agreement, and (v) such transfer shall have been made in accordance with
the applicable requirements of the Purchase Agreement. In addition, each Holder
shall have the right to assign its rights hereunder to any other Person with the
prior written consent of the Company, which consent shall not be unreasonably
withheld. The rights to assignment shall apply to the Holders (and to
subsequent) successors and assigns.

          (j)  Counterparts.  This Agreement may be executed in any number of
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.
In the event that any signature is delivered by facsimile transmission, such
signature shall create a valid binding obligation of the party executing (or on
whose behalf such signature is executed) the same with the same force and effect
as if such facsimile signature were the original thereof.

          (k)  Governing Law.  This Agreement shall be governed by and construed
in accordance with the laws of the State of Delaware, without regard to
principles of conflicts of law thereof.

          (l)  Cumulative Remedies.  The remedies provided herein are cumulative
and not exclusive of any remedies provided by law.

          (m)  Severability.  If any term, provision, covenant or restriction of
this Agreement is held to be invalid, illegal, void or unenforceable in any
respect, the remainder of the terms, provisions, covenants and restrictions set
forth herein shall remain in full force and effect and shall in no way be
affected, impaired or invalidated, and the parties hereto shall use their
reasonable efforts to find and employ an alternative means to achieve the same
or substantially the same result as that contemplated by such term, provision,
covenant or restriction.  It is hereby stipulated and declared to be the
intention of the parties that they would have executed the remaining terms,
provisions, covenants and restrictions without including any of such that may be
hereafter declared invalid, illegal, void or unenforceable.

          (n)  Headings.  The headings herein are for convenience only, do not
constitute a part of this Agreement and shall not be deemed to limit or affect
any of the provisions hereof.

          (o)  Confirmation of Effectiveness.  Within two (2) Business Days
after the Registration Statement which includes the Registrable Securities is
ordered effective by the Commission, the Company shall deliver, and shall cause
legal counsel for the Company to

                                       16
<PAGE>

deliver, to the transfer agent for such Registrable Securities (with copies to
the Holders) confirmation that the Registration Statement has been declared
effective by the Commission.

          (p)  Shares Held by the Company and its Affiliates. Whenever the
consent or approval of the Holders of a specified percentage of Registrable
Securities is required hereunder, Registrable Securities held by the Company or
its Affiliates (other than any Holder or transferees or successors or assigns
thereof if such Holder is deemed to be an Affiliate solely by reason of its
holdings of such Registrable Securities) shall not be counted in determining
whether such consent or approval was given by the Holders of such required
percentage.

                 [Remainder of Page Intentionally Left Blank]

                                       17
<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed by their respective authorized persons as of the date first
indicated above.


                                        SKYLYNX COMMUNICATIONS, INC.


                                        By: ____________________________________
                                             Name:
                                             Title:


                                        PURCHASER:


                                        Signature:


                                        By: ____________________________________
                                             Name:
                                             Title:

                                        Address:




                                        Tel No.:
                                        Fax No.:

                                       18