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                                                                    EXHIBIT 10.5


[KBRO LETTERHEAD]


                                     January 24, 2000


PRIVATE AND CONFIDENTIAL


FastComm Communications Corporation
45472 Holiday Drive
Dulles, VA 20166


Attention: Mr. Peter C. Madsen
           Chairman & Chief Executive Officer


Dear Mr. Madsen:

       This letter confirms that Kaufman Bros., L.P. ("Kaufman") has been
retained by FastComm Communications Corporation (the "Company") to act as the
Company's financial advisor and investment banker in connection with a variety
of future services including any financing, joint venture, merger, acquisition,
exchange offer, purchase or sale of capital stock or assets outside the ordinary
course of business or other similar transaction (a "Transaction").

A. Performance of Services

       Kaufman will provide the Company with a variety of services as part of an
on-going investment banking relationship. Among the services will include access
to the investment banking team for consultation and advice on corporate finance
issues as required by the Company.


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                                             FastComm Communications Corporation
                                                                January 24, 2000
                                                                          Page 2


B. Compensation for Services

       Advisory Fee

       As compensation for its investment banking services, the Company agrees
to pay Kaufman a nonrefundable retainer fee of $5,000 upon the signing of this
letter, and four subsequent monthly installments of $5,000 each. In addition,
the Company will pay Kaufman upon signing of this letter, 200,000 warrants to
purchase common stock of the Company (the "Warrants") at an exercise price of
$7.50 and shall have a term of three years from the date of issue and other
usual and customary terms including anti-dilution provisions as is in Kaufman's
standard warrant agreement.

       Placement Fee

       If a Transaction is completed with any investor identified by Kaufman
prior to the termination or expiration of this agreement (a "Target Investor"),
or any future private financing within two years thereafter by such Target
Investor, the Company will pay Kaufman a placement fee equal to 5% of the gross
proceeds raised from the sale of securities to such Target Investor (the
"Placement Fee"); plus Warrants (as described above) equal to 5% of the shares
sold to such parties in the financing, at an exercise price equal to 120% of the
price per share of the common stock (or common stock equivalent) purchased in
the Transaction.

       The Placement Fee and Warrants will NOT be owed on any investment made by
any current investor in the Company or any party pursuant to an underwritten
public offering.

       Merger Fee

       If during the term of this agreement or within one year thereafter the
Company enters into a merger, consolidation, reorganization, recapitalization,
restructuring, tender or exchange offer, negotiated purchase, leveraged buyout,
partnership or collaborative venture whereby the Company's then existing
shareholders own less than 50% of the equity of the surviving entity, the
Company will pay Kaufman a fee equal to 2% of the Aggregate Consideration of the
completed transaction (the "Transaction Fee").

       Aggregate Consideration

       Aggregate Consideration is defined and computed as the total proceeds and
all other consideration received or receivable upon the consummation of a
transaction (including payments to be made in installments), including cash,
securities, notes, consulting agreements and agreements not to compete. If a
portion of such consideration includes escrowed or



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                                             FastComm Communications Corporation
                                                                January 24, 2000
                                                                          Page 3


contingent payments (whether or not related to future earnings of operations),
Aggregate Consideration will include such payments only when the conditions for
the payment of such amounts have been satisfied, at which time the Transaction
Fee based thereon shall be paid to Kaufman.

       Out-of-Pocket Expenses

       The Company will reimburse Kaufman for all reasonable out-of-pocket
expenses incurred in performance of this agreement without regard to whether a
Transaction is consummated. Individual expenditures may not exceed $1,500
without the prior consent of the Company.

C. Rights of First Refusal

       The Company shall grant to Kaufman for a period of 18 months from the
date hereof, a first right of refusal to (i) co-manage any public offering of
the Company with any other underwriters of the Company's choosing provided that
Kaufman shall be entitled to at least 35% of the total compensation paid to the
underwriters in such a public offering; (ii) act as placement agent on any
future private financing of the Company; and (iii) to act as financial advisor
on other transactions including merger & acquisition assignments. The terms of
engagement of any future transaction, including customary investment banking
fees, will be covered under a letter of engagement separate from this letter.

       It is understood that execution of this engagement letter does not assure
that any transaction contemplated in "Rights of First Refusal" will take place.

D. Disclosure

       Any financial or other advice, descriptive memoranda or other
documentation rendered by Kaufman pursuant to this agreement may not be
disclosed publicly or to any third party in any manner without the prior written
approval of Kaufman which approval shall not be unreasonably withheld. All
non-public information given to Kaufman by the Company will be considered as
confidential information and shall be maintained as such by Kaufman until the
same becomes known to third parties or the public without release thereof by
Kaufman.

       The Company shall provide to Kaufman full, complete and accurate
information regarding the Company's business, prospects, financial condition and
any other material items. It is acknowledged and agreed that all information
provided to Kaufman is the property of the Company. The Company shall be solely
responsible for the accuracy and completeness of all disclosures regarding the
Company and shall promptly advise Kaufman of any material changes in any
information previously provided to Kaufman.


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                                             FastComm Communications Corporation
                                                                January 24, 2000
                                                                          Page 4


E. Indemnification

       The Company shall indemnify Kaufman in accordance with Exhibit I attached
hereto.

F. Engagement Period

       This engagement shall continue in effect until August 31, 2001 and shall
be automatically renewed for successive monthly periods until terminated in
writing by either the Company or Kaufman. Notwithstanding the foregoing, either
the Company or Kaufman can terminate this agreement on 90 days written notice.
The provisions of the paragraphs regarding compensation, disclosure and
indemnification shall survive the term of this Agreement.

       The Company acknowledges that Kaufman is and has been engaged as a
broker, dealer, underwriter, placement agent, finder, advisor, and deal maker,
by and for other companies in the industry in which the Company is involved.
Accordingly, the Company agrees that Kaufman shall not be required to act
exclusively for the Company and may now and, from time to time in the future, be
engaged by other companies that compete with the Company. Kaufman may, but shall
not be required to bring opportunities to the Company.

G. Miscellaneous

       This agreement sets forth the entire understanding of the parties
relating to the subject matter hereof. This agreement may not be modified or
changed, nor can any of its provisions be waived, except by written agreement
signed by all parties hereto. This agreement shall be governed by and construed
in accordance with the laws of the State of New York. The parties hereto shall
deliver notices to each other by personal delivery or by registered mail (return
receipt requested). The Company and Kaufman expressly waives all right to trial
by jury in any action or proceeding arising out of this letter agreement.

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                                             FastComm Communications Corporation
                                                                January 24, 2000
                                                                          Page 5


       Please confirm that the foregoing accurately reflects your understanding
of the agreement between us by signing on behalf of the Company and returning to
Kaufman a duplicate of this letter attached hereto, whereupon it shall become a
binding agreement between the Company and Kaufman.


                                     Very truly yours,

                                     KAUFMAN BROS., L.P.




                                     By: /s/ CRAIG KAUFMAN
                                        ----------------------------------------
                                        Craig Kaufman
                                        Chairman & Chief Executive Officer



ACCEPTED AND AGREED TO:
FASTCOMM COMMUNICATIONS CORPORATION



By: /s/ PETER C. MADSEN
   -----------------------------------
   Peter C. Madsen
   Chairman & Chief Executive Officer


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                                             FastComm Communications Corporation
                                                                January 24, 2000
                                                                          Page 6


                          EXHIBIT I -- INDEMNIFICATION

       The Company agrees that it will indemnify and hold harmless Kaufman, its
affiliates, control persons, officers, directors, employees and agents and each
person who controls Kaufman within the meaning of Section 15 of the Securities
Act of 1933 or Section 20 of the Securities Exchange Act (Kaufman and each such
entity and person being hereinafter called an "Indemnified Party") from and
against any and all losses, claims, damages, liabilities, costs or expenses
(including reasonable attorneys' and accountants' fees), as incurred, to which
such Indemnified Party may become subject which are (a) related to or arise out
of (i) actions taken or omitted to be taken (including any untrue statements
made or any statements omitted to be made) by the Company or (ii) actions taken
or omitted to be taken (including any untrue statements made or any statements
omitted to be made) by an Indemnified Party with the Company's consent or in
conformity with the instructions of, or actions taken or omitted to be taken by
the Company or (b) otherwise related to or arising out of Kaufman's acting
pursuant to this agreement. The Company also agrees to reimburse each
Indemnified Party within 30 days of submission of an invoice with respect
thereto for all expenses incurred (including fees and disbursements of counsel)
in connection with the investigation of or the preparation for or defense of any
pending or threatened formal or informal claim, action, investigation or other
proceeding caused by or arising out of or in connection with Kaufman's acting
pursuant to this agreement, whether or not Kaufman is a named party thereto and
whether or not any liability results therefrom. The Company will not be
responsible, however, for any loss, claim damage or liability for which
indemnification is sought solely pursuant to the first sentence of this
paragraph which a court of competent jurisdiction shall have determined by a
final judgment to have resulted primarily from willful misconduct or gross
negligence on the part of the Indemnified Party seeking indemnification
hereunder.

       Promptly after receipt by any Indemnified Party of notice of any
complaint or the commencement of any action or proceeding in connection with any
matter related to Kaufman's activities pursuant to the letter agreement, Kaufman
will notify the Company in writing of such complaint or of the commencement of
such action or proceeding and if the Company so elects or is requested by
Kaufman, the Company will assume the defense of such action or proceeding,
including the employment of counsel reasonably satisfactory to Kaufman and the
payment of the fees and disbursements of such counsel, in which event the
Company shall not be obligated to pay the fees and disbursements of separate
counsel for Kaufman in such action. However, failure by Kaufman to so notify the
Company of such claim or such commencement shall not relieve the Company from
any obligation hereunder except to the extent that such failure shall result in
prejudice to the Company. In the event, however, that Kaufman's legal counsel
shall determine that defenses may be available to an Indemnified Party that are
different from or in addition to


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                                             FastComm Communications Corporation
                                                                January 24, 2000
                                                                          Page 7


those available to the Company or that there is or could reasonably be expected
to be a conflict of interest by reason of the Company and an Indemnified Party
having common counsel in any action or proceeding, or if the Company has not
assumed the defense of any action or proceeding, then Kaufman may employ
separate counsel to represent or defend it or any Indemnified Party in any such
action or proceeding in which it or such Indemnified Party may become involved
or is named as defendant and the Company shall pay the fees and disbursements,
as Incurred by such separate counsel; provided that the Company shall not be
obligated to pay the fees and disbursements of more than one such separate
counsel for any one such action or proceeding in any one jurisdiction.

       If for any reason the foregoing indemnification is unavailable to
Kaufman, or insufficient to hold it harmless, then the Company shall contribute
to the amount paid or payable by Kaufman as a result of such loss, claim, damage
or liability in such proportion as is appropriate to reflect the relative
benefits received by the Company and its stockholders on the one hand and
Kaufman on the other; provided that in no event will the aggregate contribution
by Kaufman hereunder exceed the amount of fees actually received by Kaufman
pursuant to this agreement. It is agreed that the relative benefit of the
Company on the one hand and of Kaufman on the other hand with respect to any
financing shall be deemed to be in the same proportion as (x) the Aggregate
Consideration paid or proposed to be paid in such financing (whether or not such
financing is consummated) bears (y) to the fee payable to Kaufman with respect
to such financing pursuant to this agreement.

       The reimbursement, indemnity and contribution obligations of the Company
under this paragraph shall be in addition to any liability which the Company may
otherwise have and shall be binding upon and inure to the benefit of any
successors, assigns, heirs and personal representatives of the Company, Kaufman
and any such person. The provisions of this Exhibit I shall survive the
termination and expiration of this agreement.