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                                                                   Exhibit 10.29

                               As of March 2, 1999




Mr. Marc H. Bell
c/o Globix Corporation
295 Lafayette St.
New York, N.Y. 10012

Dear Mr. Bell:

                  This is to confirm our agreement that, effective as of March
2, 1999 (the "Effective Date"), the Employment Agreement between us dated as of
April 10, 1998 (hereinafter referred to as the "Agreement") is amended as
follows:

                   1.      Section 3.03(c) of the Agreement is hereby deleted in
                  its entirety and the following substituted therefor:

                           Executive shall be granted an option to purchase that
                  number of shares of Common Stock as shall equal 25% of the
                  difference between the number of shares of Common Stock issued
                  and outstanding on the date of closing of the currently
                  proposed public offering (after giving effect to the issuance
                  of the offering shares) and the number issued and outstanding
                  as of October 1, 1998, provided, however, that (i) for
                  purposes of this calculation, treasury shares shall not be
                  deemed to be issued and outstanding and (ii) any increase
                  which is the result of stock splits or stock dividends, shall
                  not be taken into account. Such stock option shall be
                  non-qualified stock options for purposes of the Internal
                  Revenue Code of 1986, as amended. The exercise price of such
                  stock options shall be the offering price of the Company's
                  common stock to the public in the currently proposed offering.
                  Such stock option shall be exercisable in whole or in part
                  after the date of grant, which shall be concurrent with the
                  closing of the public offering, and shall terminate on the
                  tenth anniversary of the date of grant. Such stock option
                  shall be evidenced by an agreement containing such other terms
                  and conditions as the Company and Executive shall agree. The
                  Company shall take all such steps as shall be necessary to
                  effectuate the foregoing including, without limitation,
                  proposing this amendment for approval by the Company's
                  stockholders and reserving a sufficient number of authorized
                  but unissued shares to permit the purchase of the shares
                  pursuant to the stock options granted hereunder.

                   2. This amendment is conditioned upon the closing of the
                  currently proposed public offering on or before April 30,
                  1999.

                   3. In all other respects, the Agreement shall continue in
                  full force and effect in accordance with its original terms,
                  as amended.
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                  If the foregoing sets forth a correct statement of our
agreement, please sign the duplicate hereof in the place indicated and return it
to us.


                                            Very truly yours,

                                            GLOBIX CORPORATION



                                            By /s/ Robert B. Bell           
                                            ---------------------           
                                            Robert B. Bell
                                            Executive Vice President



ACCEPTED AND AGREED:



/s/ Marc H. Bell             
----------------             
 Marc H. Bell