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                                                                     Exhibit 3.2
                                  AMENDMENT TO
                            LIMITED LIABILITY COMPANY
                               OPERATING AGREEMENT
                                       OF
                               LOCAL FIBER, L.L.C.



         THIS AMENDMENT TO LIMITED LIABILITY COMPANY OPERATING AGREEMENT (this
"Amendment") of Local Fiber, L.L.C., a New York limited liability company (the
"Company"), is entered into and shall be effective as of November 13, 1997, by
and among the Company and the members executing this Amendment. Capitalized
terms used without definitions herein have the respective meaning set forth in
the Operating Agreement (as defined below).

                                    RECITALS

         WHEREAS, the Management Board desires to amend the Limited Liability
Company Operating Agreement of Local Fiber, L.L.C., dated as of March 22, 1996,
by and among the Company and the persons referenced therein (the "Operating
Agreement"), to add FiberNet Telecom, Inc., a Delaware corporation ("FiberNet")
as a party thereto and to acknowledge that SMFS, Inc., LTJ Group, Inc. and LPS
Consultants, Inc. (collectively, the "Members") are no longer members of the
Company and have no further rights or obligations under the Operating Agreement;

         WHEREAS, the Members desire that Schedule A to the Operating Agreement
be amended to reflect the change in ownership of the Company; and

         NOW, THEREFORE, in consideration of the premises and the agreements,
provisions and covenants herein contained and for other good and valuable
consideration, the sufficiency and receipt of which are hereby acknowledged, it
is mutually agreed as follows:

                                    ARTICLE I

         SECTION 1.1. ADDITION OF FIBERNET AS A PARTY. FiberNet by execution of
this Amendment hereby agrees to be bound by the terms and conditions of the
Operating Agreement as a member and agrees to be subject to the provisions of
the Operating
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Agreement applicable to members as though originally a signatory and party to
the Operating Agreement.

         SECTION 1.2. CONSENT TO TRANSFER OF MEMBERS' INTERESTS. Pursuant to the
Contribution Agreement dated as of November 13, 1997 by and among the
signatories listed thereto, the Members hereby consent to the transfer of all of
their respective membership interests in the Company to FiberNet Telecom, Inc.

         SECTION 1.3. AMENDMENT TO SCHEDULE A. Schedule A to the Operating
Agreement is hereby amended and restated as of the effective date of this
Amendment to read in its entirety as Schedule A attached hereto.

                                   ARTICLE II

         SECTION 2.1. RELATION TO THE OPERATING AGREEMENT. The provisions of
this Amendment shall be deemed to be effective as of November 13, 1997 or
immediately upon the execution and delivery hereof. This Amendment and all the
terms and provisions herein contained shall form a part of the Operating
Agreement as fully and with the same effect as if all such terms and provisions
had been set forth in the Operating Agreement. The Operating Agreement shall
remain and continue in full force and effect in accordance with the terms and
provisions thereof, as amended by this Amendment, and the Operating Agreement
and this Amendment shall be read, taken and construed together as one
instrument.


                           [Intentionally Left Blank]
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         IN WITNESS WHEREOF, the persons signing this Amendment below
conclusively evidence their agreement to the terms and conditions of the
Operating Agreement by so signing here.

CLASS A MEMBERS

FIBERNET TELECOM, INC.


By:/s/John J. Marchaesi
  --------------------------------
Name: John J. Marchaesi
Title: VP Finance

SMFS, INC.

By:/s/ Santo Petrocelli
  --------------------------------
Name: Santo Petrocelli
Title: President

LTJ GROUP, INC.

By:/s/ J. A. Tortoretti
  --------------------------------
Name: J.A. Tortoretti
Title: President

LPS CONSULTANTS, INC.

By:/s/ Lawrence S. Polan
  --------------------------------
Name: Lawrence S. Polan
Title:   President

CLASS B MEMBER

NATIONAL FIBER NETWORK, INC.

By:
  --------------------------------
Name:
Title:
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                                   SCHEDULE A

                                 CLASS A MEMBERS

         NAME AND ADDRESS                              PERCENTAGE INTEREST

         FiberNet Telecom, Inc.                                 90%
         121 Erie Canal Drive, Suite A
         Rochester, New York 14626


                                 CLASS B MEMBERS


         NAME AND ADDRESS                              PERCENTAGE INTEREST

         NFN, Inc.                                             10%
         60 Hudson Street
         New York, New York 10013