Exhibit 10.1

                                  AMENDMENT TO
                       PREFERRED STOCK PURCHASE AGREEMENT


         This Amendment to the Preferred Stock Purchase Agreement dated May 12,
2000 (the "Purchase Agreement"), by and between TeraComm Research, Inc.
("TeraComm") and Atlantic Technology Ventures, Inc. ("Atlantic") is dated as of
July 18, 2000 (the "Amendment").

         WHEREAS, Atlantic has since the date of the Purchase Agreement made
Subsequent Payments to TeraComm in the amount of $750,000; and

         WHEREAS, the parties wish to modify their rights and obligations with
respect to Subsequent Payments under the Purchase Agreement.

         NOW, THEREFORE, the parties agree as follows:

         1. Schedule 1.2 of the Purchase Agreement is hereby amended to provide
that the remaining $4 million of Subsequent Payments (including the $1 million
payments due on August 12, 2000 and November 12, 2000) are not be due and
payable until the Technology Milestone attached hereto as Attachment A has been
achieved. Within ten (10) days of TeraComm's achieving the Technology Milestone,
Atlantic shall make the $1 million Subsequent Payment currently due on August
12, 2000 (the "Second Subsequent Payment") and shall thereafter make the
remaining three $1 million Subsequent Payments on the next three-month
anniversary dates of the date of such first $1 million Subsequent Payment. The
other provisions of Section 1.2 shall remain in effect, including subparagraph
(b) with respect to failure to make timely Subsequent Payments.

         2. TeraComm shall keep the representatives of Atlantic on the TeraComm
Board of Directors informed as to progress toward achieving the Technology
Milestone. If TeraComm believes it has achieved the Technology Milestone, it
will notify Atlantic in writing thereof. If Atlantic disagrees that TeraComm has
achieved the Technology Milestone, it shall so state in writing within five (5)
business days of the notice from TeraComm. If the matter cannot be resolved
within the following ten (10) business days by discussions between the parties,
the matter shall be deemed submitted to arbitration administered by the American
Arbitration Association in accordance with its commercial arbitration rules. The
place of arbitration shall be Boston, Massachusetts. With respect to the
arbitration, the parties will attempt to agree on an arbitrator with sufficient
background in fiberoptic communications development to determine the dispute. If
the parties cannot agree on such person within thirty (30) days of submission of
the matter to arbitration, each party shall pick an arbitrator with relevant
experience and those two parties shall pick a third arbitrator, and all three
will hear the arbitration.

         3. Failure of Atlantic to make the Second Subsequent Payment by
midnight at the end of December 30, 2000 (whether or not TeraComm has reached
the Technology Milestone), will at the election of TeraComm be deemed to
constitute failure by Atlantic to timely make a Subsequent Payment. That
election must be voted on by the Board of Directors of TeraComm, with all
members entitled to participate in the decision (regardless of conflict of
interest).

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         4. All terms used as defined terms herein and not otherwise defined
herein shall have the meaning given them in the Purchase Agreement.

         5. This Amendment amends the Purchase Agreement only to the extent
stated herein. All other provisions of the Purchase Agreement shall remain in
full force and effect.

         IN WITNESS WHEREOF, the parties have executed this Amendment as of the
date first above written.

                                      TERACOMM RESEARCH, INC.


                                      By: /s/ Kenneth Puzey
                                         --------------------
                                      Its: President


                                      ATLANTIC TECHNOLOGY VENTURES, INC.


                                      By: /s/ Frederic P. Zotos
                                         -------------------------------
                                      Its: President


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