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                                                                   EXHIBIT 10.20

                              EMPLOYMENT AGREEMENT

      THIS EMPLOYMENT AGREEMENT (this "Agreement"), dated as of July 15, 2004
(the "Effective Date"), by and between IPC Information Systems, LLC, a Delaware
limited liability company (the "Employer"), and Timothy Whelan (the "Employee").

      WHEREAS, the Employee possesses skills, experience and knowledge that are
of value to the Employer; and

      WHEREAS, the Employer desires to enlist the services and employment of the
Employee on behalf of the Employer as its Chief Financial Officer, and the
Employee is willing to render such services on the terms and conditions set
forth herein.

      NOW, THEREFORE, in consideration of the mutual covenants contained herein,
the sufficiency of which is hereby acknowledged, the parties hereto agree as
follows:

      1. Employment Term. Subject to the terms and conditions of this Agreement,
the Employer hereby agrees to employ the Employee hereunder, and the Employee
hereby agrees to be employed by the Employer hereunder, for the period
commencing on the Effective Date and ending on the second anniversary of the
Effective Date, unless terminated sooner as hereinafter provided (such period,
the "Employment Term").

      2. Duties.

            (a) During the Employment Term, the Employee shall serve as the
Chief Financial Officer of the Employer, and in such capacity shall use his best
energies and abilities in the performance of such duties, services and
responsibilities customarily associated with such position as determined from
time to time by the Chief Executive Officer of the Employer (the "CEO Board") or
the Board of Directors of the Employer (the "CEO Board") and such other duties
as reasonably requested by the CEO or Board. In performing such duties, services
and responsibilities, the Employee will report directly to the CEO.

            (b) During the Employment Term, the Employee shall devote his full
business time, attention and best efforts to the performance of his duties
hereunder and shall not, without the consent of the CEO and the Board provide
services as an

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employee, director or consultant or other independent contractor to or in
respect of any business or entity other than the Employer.

      3. Compensation. In full consideration of the performance by the Employee
of the Employee's obligations during the Employment Term (including any service
as a member of the Board and in any position with any affiliate of the Employer
or otherwise on behalf of the Employer), the Employee shall be compensated as
follows:

            (a) Base Salary. During the Employment Term, the Employee shall
receive a base salary (the "Base Salary") at an annual rate of $234,000, payable
in accordance with the normal payroll practices of the Employer in effect from
time to time. During the Employment Term, the Base Salary shall be subject to
annual increase (but not decrease) as determined in the sole discretion of the
Board.

            (b) Annual Target Bonus. For each fiscal year of the Employer in
effect during the Employment Term, the Employee shall be eligible to receive a
cash bonus of up to 50% of his Base Salary (the "Target Bonus") upon the
attainment of performance goals set in advance by the CEO and Board. All such
bonuses shall be paid after the completion of the Employer's financial
statements for the applicable fiscal year as and when bonuses are paid to
members of senior management generally.

            (c) The Employee shall be solely responsible for federal, state and
local taxes imposed on the Employee by reason of any compensation and benefits
provided under this Agreement, and all such compensation and benefits shall be
subject to all applicable withholding taxes.

      4. Benefits.

            a) During the Employment Term, the Employee shall be entitled to
participate in the employee benefit plans, policies, programs and arrangements,
as may be amended from time to time, that are provided generally to senior
executives of the Employer to the extent the Employee meets the eligibility
requirements for any such plan, policy, program or arrangement.

            b) Upon the presentation of proper documentation, the Employer shall
reimburse the Employee for all reasonable attorneys' fees incurred in connection
with the negotiation of this Agreement, up to a maximum of$1,500.

      5. Vacations. During the Employment Term, the Employee shall be entitled
to four weeks of paid vacation per each full calendar year. Such vacation time
shall be provided in accordance with the Employer's policies with respect to
carry-over of vacation days.

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      6. Termination of the Employment Term. The Employment Term shall terminate
upon the earliest of:

            (a) The second anniversary of the Effective Date;

            (b) The death of the Employee;

            (c) The Disability of the Employee; and

            (d) The termination of the Employee's employment by the Employer
for Cause or without Cause.

      For purposes of this Agreement, the terms "Cause" and "Disability" are
each as defined in the Employer's Amended and Restated 2002 Stock Option Plan.

      7. Termination Payments.

            (a) Subject only to Section 7(b), upon termination of the Employee's
employment during the Employment Term, the sole obligation of the Employer to
make any cash payment to the Employee shall be to pay the Employee (i) any
portion of the Base Salary and bonus which has been earned but unpaid as of the
date of the Employee's termination of employment with the Employer (the
"Termination Date") and (ii) reimbursement of reasonable and necessary business
expenses incurred by the Employee in connection with the Employee's employment
on behalf of the Employer on or prior to the Termination Date but not previously
paid to the Employee (collectively, the "Accrued Compensation").

            (b) If the employment of the Employee is terminated during the
Employment Term by the Employer pursuant to Section 6(d) other than for Cause,
the sole obligation of the Employer to make any cash payment to the Employee
other than the payment of the Accrued Compensation shall be to pay the Employee
an amount of severance pay equal to the sum of 75% of the Base Salary and 75% of
the Target Bonus, each as in effect as of the Termination Date. Such severance
pay shall be paid in twelve substantially equal monthly installments commencing
within 30 days of the Termination Date; provided, however, that in the event the
Employee breaches any of the covenants set forth in Section 8 hereof following
the Termination Date, all severance payments shall cease and the Employer shall
have no further obligations under this Section 7(b). The Company will also, for
the period during which it is making such severance payments to the Employee,
provide the Employee and his dependents, at the Company's cost, continued group
medical insurance coverage, so long as such continuation is available pursuant
to a valid election for continuation of coverage. The obligation of the Employer
to pay the severance pay pursuant to this Section 7(b) shall be conditioned on
the Employee's execution of a general release in form satisfactory to the
Employer.

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      8. Employee Covenants.

      (a) Unauthorized Disclosure. The Employee agrees and understands that in
the Employee's position with the Employer, the Employee has been and will be
exposed to and has and will receive information relating to the confidential
affairs of the Employer and its affiliates, including, without limitation,
technical information, intellectual property, business and marketing plans,
strategies, customer information, software, other information concerning the
products, promotions, development, financing, expansion plans, business policies
and practices of the Employer and its affiliates and other forms of information
considered by the Employer and its affiliates to be confidential and in the
nature of trade secrets (including, without limitation, ideas, research and
development, know-how, formulas, technical data, designs, drawings,
specifications, customer and supplier lists, pricing and cost information and
business and marketing plans and proposals) (collectively, the "Confidential
Information"). The Employee agrees that at all times during the Employee's
employment with the Employer and thereafter, the Employee shall not disclose
such Confidential Information, either directly or indirectly, to any third
person or entity without the prior written consent of the Employer. This
confidentiality covenant has no temporal, geographical or territorial
restriction. Upon termination of the Employee's employment with the Employer,
the Employee shall promptly supply to the Employer all property, keys, notes,
memoranda, writings, lists, files, reports, customer lists, correspondence,
tapes, disks, cards, surveys, maps, logs, machines, technical data and any other
tangible product or document which has been produced by, received by or
otherwise submitted to the Employee during or prior to the Employee's employment
with the Employer, and any copies thereof in his (or capable of being reduced to
his) possession.

      (b) Non-competition. By and in consideration of the Employer's entering
into this Agreement and the payments to be made and benefits to be provided by
the Employer hereunder, and further in consideration of the Employee's exposure
to the proprietary information of the Employer and its affiliates, the Employee
agrees that the Employee shall not, during the Employee's employment with the
Employer and thereafter during the one-year period following the Termination
Date (the "Non-competition Term"), directly or indirectly, own, manage, operate,
join, control, be employed by, or participate in the ownership, management,
operation or control of, or be connected in any manner with, including, without
limitation, holding any position as a shareholder, director, officer,
consultant, independent contractor, employee, partner, or investor in, any
Restricted Enterprise; provided, that in no event shall ownership of 1% or less
of the outstanding equity securities of any issuer whose securities are
registered under the Securities Exchange Act of 1934, as amended, standing
alone, be prohibited by this Section 8(b). For purposes of this paragraph,
"Restricted Enterprise" shall mean any person, corporation, partnership or other
entity that is engaged, directly or indirectly, in (a) the design, manufacture,
installation, servicing, consultation and other professional

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services and applications of Turret Systems (as defined below); (b) the design
and implementation of the in-building cabling and infrastructure necessary for
customers; (c) the design, provisioning, installation or servicing of
telecommunication services for trading floors; or (d) managed services in
connection with trading organizations as provided by the Employer during the
Employee's employment with the Employer, in each case in the United States or in
any other geographic location where the Employer or any of its affiliates do
business. For purposes of this Agreement, the term "Turret Systems" shall mean
telecommunications equipment and software to enable communications (including
voice, video and data) primarily among traders, counterparties and associated
support personnel. During the one-year period following the Termination Date,
upon request of the Employer, the Employee shall notify the Employer of the
Employee's then current employment status.

      (c) Non-solicitation. During the Non-competition Term, the Employee shall
not (1) contact, induce or solicit (or assist any person to contact, induce or
solicit) any person which has a business relationship with the Employer or of
any of its affiliates to terminate, curtail or otherwise limit such business
relationship, or (2) contact, induce or solicit (or assist any person to
contact, induce or solicit) for employment any person who is, or within six
months prior to the date of such action was, an employee of the Employer or any
of its affiliates. Notwithstanding the foregoing, the non-solicitation
provisions herein shall not apply to any person who served as the Employee's
secretary/administrative assistant, during the Employee's employment with the
Company.

      (d) Remedies. The Employee agrees that any breach of the terms of this
Section 8 would result in irreparable injury and damage to the Employer for
which the Employer would have no adequate remedy at law; the Employee therefore
also agrees that in the event of said breach or any threat of breach, the
Employer shall be entitled to an immediate injunction and restraining order to
prevent such breach and/or threatened breach and/or continued breach by the
Employee and/or any and all persons and/or entities acting for and/or with the
Employee, without having to prove damages, in addition to any other remedies to
which the Employer may be entitled at law or in equity. The terms of this
paragraph shall not prevent the Employer from pursuing any other available
remedies for any breach or threatened breach hereof, including, without
limitation, the recovery of damages from the Employee. The Employee and the
Employer further agree that the provisions of the covenants contained in this
Section 8 are reasonable and necessary to protect the businesses of the Employer
and its affiliates because of the Employee's access to Confidential Information
and his material participation in the operation of such businesses. Should a
court or arbitrator determine, however, that any provision of the covenants
contained in this Section 8 is not reasonable or valid, either in period of
time, geographical area, or otherwise, the parties hereto agree that such
provision should be interpreted and enforced to the maximum extent which such
court or arbitrator deems reasonable or valid.

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      The existence of any claim or cause of action by the Employee against the
Employer or any of its affiliates, whether predicated on this Agreement or
otherwise, shall not constitute a defense to the enforcement by the Employer of
the covenants contained in this Section 8.

      9. Proprietary Rights. The Employee shall disclose promptly to the
Employer any and all inventions, discoveries, improvements and patentable or
copyrightable works initiated, conceived or made by him, either alone or in
conjunction with others, during the Employee's employment with the Employer and
related to the business or activities of the Employer and its affiliates, and he
assigns all of his interest therein to the Employer or its nominee. Whenever
requested to do so by the Employer, the Employee shall execute any and all
applications, assignments or other instruments which the Employer shall deem
necessary to apply for and obtain trademarks, patents or copyrights of the
United States or any foreign country or otherwise protect the interests of the
Employer and its affiliates therein. These obligations shall continue beyond the
end of the Employee's employment with the Employer with respect to inventions,
discoveries, improvements or copyrightable works initiated, conceived or made by
the Employee while employed by the Employer and shall be binding upon the
Employee's employers, assigns, executors, administrators and other legal
representatives.

      10. Employee Representations. The Employee represents and warrants that
(i) he is not subject to any contract, arrangement, policy or understanding, or
to any statute, governmental rule or regulation, that in any way limits his
ability to enter into and fully perform his obligations under this Agreement and
(ii) he is not otherwise unable to enter into and fully perform his obligations
under this Agreement.

      11. Indemnification. During the Employee's employment and thereafter, the
Employer agrees to indemnify, including, without limitation, advancement of all
costs and fees, the Employee from and against any liability and expenses arising
by reason of the Employee's acting as an officer or director of the Employer or
any of its subsidiaries, in accordance with and to the fullest extent permitted
by law. During the Employment Term, the Employer shall maintain commercially
reasonable Directors and Officers liability insurance, under which the Employee
will be a covered person. Such liability insurance shall have such terms and
policy limits of coverage as are determined appropriate by the Board.

      12. Non-Waiver of Rights; Disputes.

      (a) The failure to enforce at any time the provisions of this Agreement or
to require at any time performance by any other party of any of the provisions
hereof shall in no way be construed to be a waiver of such provisions or to
affect either the validity of this Agreement or any part hereof, or the right of
any party to enforce each and every provision in accordance with its terms.

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      (b) No dispute relating to or arising under this Agreement shall be
subject to mediation or arbitration, and, if such dispute is subject to a trial,
such trial shall be a jury trial.

      13. Notices. Every notice relating to this Agreement shall be in writing
and shall be given by personal delivery or by registered or certified mail,
postage prepaid, return receipt requested.

      14. Binding Effect/Assignment. This Agreement shall inure to the benefit
of and be binding upon the parties hereto and their respective heirs, executors,
personal representatives, estates, successors (including, without limitation, by
way of merger) and assigns. Notwithstanding the provisions of the immediately
preceding sentence, the Employee shall not assign all or any portion of this
Agreement without the prior written consent of the Employer.

      15. Entire Agreement; Modification. This Agreement sets forth the entire
understanding of the parties hereto with respect to the subject matter hereof
and supersedes and replaces all prior agreements, negotiations and/or
representations, written or oral, between the Parties to the extent they relate
in any way to the employment, termination of employment, compensation and
employee benefits of the Employee, other than the Non-Qualified Stock Option
Agreements entered into between the Parties, dated as of April 5, 2002, April
25, 2003, July 9, 2003, and October 20, 2003, respectively and the Key Employee
Stock Purchase Agreement between the Parties, dated as of July 25, 2002 and
related Secured Promissory Note and Security Agreement. This Agreement may not
be amended, nor may any provision hereof be modified or waived, except by an
instrument in writing duly signed by the parties.

      16. Severability. If any provision of this Agreement, or any application
thereof to any circumstances, is invalid, in whole or in part, such provision or
application shall to that extent be severable and shall not affect other
provisions or applications of this Agreement.

      17. Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of New York, without reference to the
principles of conflict of laws.

      18. Headings. The headings contained herein are solely for the purposes of
reference, are not part of this Agreement and shall not in any way affect the
meaning or interpretation of this Agreement.

      19. Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed to be an original but all of which
together shall constitute one and the same instrument.

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      IN WITNESS WHEREOF, the Employer has caused this Agreement to be executed
by authority of the Board, and the Employee has hereunto set his hand, effective
as of the Effective Date.

                                                IPC Information Systems, LLC.

                                                By: /s/ Lance Boxer
                                                    ---------------------------

                                                Name:___________________________

                                                Its: ___________________________


                                                       /s/ Timothy Whelan
                                                --------------------------------
                                                        Timothy Whelan