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                                                                   EXHIBIT 10.49


                           Enron North America Corp.
                               1400 Smith Street
                             Houston, Texas 77002

                               February 10, 2000

FirstWorld Communications, Inc.
Attn: Mr. Jeffrey Dykes
8390 E. Crescent Parkway, Suite 300
Greenwood Village, CO 80111

Colorado Spectra 1, L.L.C.
Colorado Spectra 2, L.L.C.
Colorado Spectra 3, L.L.C.
Colorado Spectra 4, L.L.C.
Attn: Donald Sturm
3033 East First Avenue, Suite 200
Denver, Colorado 80206

TPG Partners  III L.P.
T3 Partners L.P.
Colony Investors IV L.P.
Attn: Rick Ekelbery
c/o Texas Pacific Group
201 Main Street
Suite 2420
Fort Worth TX 76102


          Re: Assignment of Rights, Assumption of Obligations and Termination of
Rights of Enron North America Corp. (formerly Enron Capital & Trade Resources
Corp.) (together with all its affiliates, "ENA"), Nina I, L.L.C., ECT Merchant
Investments Corp. and Sundance Assets, L.P. (together with ENA, the "Enron
Entities") with respect to the Amended and Restated Investor Rights Agreement
(the "Agreement"), dated as of April 13, 1998, as amended, among the Enron
Entities, FirstWorld Communications, Inc. (formerly SpectraNet International)
("FirstWorld"), Colorado Spectra 1, L.L.C., Colorado Spectra 2, L.L.C., Colorado
Spectra 3, L.L.C., Colorado Spectra 4, LLC (collectively, the "Sturm Entities"),
and the other individuals and entities signatory thereto

Gentlemen:

          This letter will evidence the agreement of the parties, in accordance
with Section 5.5 of the Agreement, to (1) the assignment of certain rights by
the Enron Entities and the substitution of TPG Partners III L.P., T3 Partners
L.P. and Colony Investors IV, L.P., each a Delaware limited
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partnership, (collectively, the "Purchasers") for the Enron Entities with
respect to certain rights and obligations set forth in the Agreement; (2) the
adoption of the Agreement by the Purchasers; and (3) the termination of certain
rights of the Enron Entities under the Agreement.


          1.  Assignment.  Effective upon the closing of the sale of  FirstWorld
              ----------
securities held by ENA to the Purchasers pursuant to the Stock Purchase
Agreement dated as of February 10, 2000 by and between ENA and ECT Merchant
Investment Corp. and the Purchasers (the "Closing Date"), the Enron Entities
hereby assign to the Purchasers the following rights under the Investor Rights
Agreement:  (a) their rights to register "Registrable Securities," as defined in
the Agreement, pursuant to Section 2 of the Agreement with respect to the
FirstWorld securities transferred to each of the Purchasers by the Enron
Entities upon the Closing; (the Enron Entities will retain their registration
rights with respect to the FirstWorld securities retained by the Enron Entities
after the Closing (the "Retained Securities"), (b) their rights of first refusal
under Section 4 of the Agreement, and (c) rights to FirstWorld information under
Section 3 of the Agreement; (the Enron Entities will retain such rights with
respect to the Retained Securities).  FirstWorld acknowledges and agrees that
the requirements of clause (A) of the proviso to Section 2.10 have been
satisfied.  The Sturm Entities and FirstWorld hereby acknowledge and agree that
all requirements of the Agreement for the assignment of the rights described
herein have been met and that this letter agreement is effective to assign such
rights.

          The parties hereto further consent to the amendment of the Agreement
pursuant to Section 5.5(a), effective upon the Closing, by replacing each
reference to "Enron" with a reference to "TPG III Partners, L.P." in Sections
2.11, 2.12, 5.5(a) and 5.5(b).

          2.  Adoption.  Pursuant to Section 2.1(a)(ii)(A) and clause (B) of the
              --------
proviso to Section 2.10 of the Agreement, each of the Purchasers hereby agrees
to be bound by the terms of, and subject to all of the restrictions set forth
in, the Agreement.  FirstWorld and the Sturm Entities hereby acknowledge
satisfaction of the requirements of Section 2.1(a)(ii)(B) with respect to ENA's
sale to the Purchasers.

          3.  Termination of Rights.  All remaining rights and obligations of
              ---------------------
the Enron Entities under the Agreement, including the registration rights under
Section 2 with respect to the Retained Securities, will terminate upon the later
to occur of: (i) the Closing and (ii) the consummation of an offering of the
FirstWorld Series B Common Stock registered pursuant to the Securities Act of
1933, as amended, and the listing of the Series B Common Stock for trading on
the New York Stock Exchange or quotation on the Nasdaq National Market.
Notwithstanding the foregoing, the rights of the Enron Entities under Section 4
of the Agreement shall terminate upon the Closing.

          4.  Assignees.  If any of the Purchasers assigns any of its rights to
              ---------
purchase FirstWorld securities from any of the Enron Entities, the Purchaser
shall require the assignee to become a party to the Agreement and this letter
agreement by agreeing in writing to be bound by all the terms of both
agreements. Notwithstanding anything contained in the Agreement to the contrary,


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FirstWorld and the Sturm Entities agree that so long as the assignee is an
affiliate of one of the Purchasers no notice or information disclosure is
required to permit the assignee to become a party to the agreements.

          5.  Consent.  The Purchasers and the Enron Entities acknowledge and
              -------
agree that the Enron Entities have previously consented under Section 5.5 of the
Agreement to an amendment to the Agreement which provides Lucent Technologies,
SAIC Venture Capital Corp. and Microsoft Corporation with S-3, demand and
piggyback registration rights.  In addition, the Purchasers and the Enron
Entities hereby consent to an amendment to the Agreement to provide TPG
FirstWorld I, LLC with identical demand, S-3 and piggyback rights with respect
to the shares of  Series B common  stock of  FirstWorld purchased by TPG
FirstWorld I, LLC in a private placement which will close concurrently with
FirstWorld's IPO.

          6.  Notice for the Purchasers.  Pursuant to Section 2.10 of the
              -------------------------
Agreement, the address for each of the Purchasers is as provided on the first
page hereto.

                          (Signature pages to follow)



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          Please evidence your agreement with the foregoing by signing this
letter and the enclosed duplicate counterparts in the space provided below and
returning one copy to ENA, attention: Anne Koehler at the address provided
above.


                                    Very truly yours,

                                    ENRON NORTH AMERICA CORP.


                                    By:_______________________________________
                                    Name:_____________________________________
                                    Title:____________________________________

                                    SUNDANCE PARTNERS, L.P.

                                    By:_______________________________________
                                    Name:_____________________________________
                                    Title:____________________________________

                                    NINA I, LLC

                                    By:_______________________________________
                                    Name:_____________________________________
                                    Title:____________________________________

                                    ECT MERCHANT INVESTMENTS CORP.

                                    By:_______________________________________
                                    Name:_____________________________________
                                    Title:____________________________________



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AGREED TO AND ACCEPTED
this 10th day of February, 2000.


FIRSTWORLD COMMUNICATIONS, INC.               COLORADO SPECTRA 4, L.L.C.


By:______________________________             By:______________________________
Name:_________________                        Name:_________________
Title:___________________________             Title:___________________________


COLORADO SPECTRA 1, L.L.C.                    TPG PARTNERS III L.P.


By:______________________________             By:______________________________
Name:_________________                        Name:_________________
Title:___________________________             Title:___________________________


COLORADO SPECTRA 2, L.L.C.                    T3 PARTNERS L.P.


By:______________________________             By:______________________________
Name:_________________                        Name:_________________
Title:___________________________             Title:___________________________


COLORADO SPECTRA 3, L.L.C.                    COLONY INVESTORS IV L.P.


By:______________________________             By:______________________________
Name:_________________                        Name:_________________
Title:___________________________             Title:___________________________



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