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                                                                    EXHIBIT 10.4

                                                                  EXECUTION COPY

                    AMENDED AND RESTATED LABOR POOL AGREEMENT

               AMENDED AND RESTATED LABOR POOL AGREEMENT made as of this 18th
day of December, 1997 (the "Agreement"), by and between KLEINKNECHT ELECTRIC
COMPANY, INC. (NJ) ("KEC-NJ"), of 202 Rutgers Street, Maplewood, New Jersey
07040, and IPC INFORMATION SYSTEMS, INC. ("IPC") of 88 Pine Street, New York, NY
10005.

               WHEREAS, KEC-NJ and IPC heretofore were both signatories to
separate collective bargaining agreements with Local 164T IBEW, pursuant to
which agreements both corporations employed technicians who were members of said
local; and

               WHEREAS, KEC-NJ is a domestic corporation controlled by Richard
Kleinknecht and Peter Kleinknecht and their respective children; and

               WHEREAS, in October of 1991, the stock of IPC was acquired by
Knight Ventures, Inc., a corporation also controlled by Richard Kleinknecht and
Peter Kleinknecht; and

               WHEREAS, after such acquisition it was determined to be in the
best interests of both IPC and KEC-NJ to continue to employ Local 164T members
on a pooled basis, and under the terms of KEC-NJ's collective bargaining
agreement; and

               WHEREAS, Local 164T has orally agreed to the institution and
maintenance of such a pooling arrangement; and

               WHEREAS, the parties desire to memorialize their pooling
arrangement and wish to provide for its continuance for an extended period of
time.

               NOW, THEREFORE, the parties agree as follows:

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               1.   KEC-NJ and IPC acknowledge their continued intention to
employ on a pooled basis only those employees engaged by IPC and performing work
for IPC who are represented by IBEW Local 164T, ("Pooled Employees") pursuant to
all of the terms and conditions of KEC-NJ's collective bargaining agreement,
including, without limitation, the continued payment of fringe benefit
contributions provided for in such collective bargaining agreement.

               2.   It is the intention of the parties that, as to Pooled
Employees while engaged in IPC work, IPC shall have the same obligations and
duties with regard to such employees as if IPC continued to have a direct
contract with Local 164T. Accordingly, it is acknowledged by IPC that it is
familiar with, and has a copy of, KEC-NJ's collective bargaining agreement. IPC
agrees, as to its Pooled Employees, to assume and abide by all of the terms and
conditions of such collective bargaining agreement and, together with KEC-NJ, to
do all things required by such agreement, and not to take any action which would
be a breach thereof.

               3.   KEC-NJ agrees to be responsible for the preparation, on
behalf of IPC, of all payrolls, payroll tax returns and union reports and fringe
benefits and for the making of all appropriate payments to Pooled Employees,
governmental agencies, insurance carriers, if applicable, and to trustees of the
Local 164T fringe benefit funds (collectively, the "Payroll") for Pooled
Employees engaged in IPC work under KEC-NJ's collective bargaining agreement and
as to whom KEC-NJ has been notified by IPC to make such payments. The parties
shall promptly supply each other with all accurate and relevant information and
shall maintain such information for their mutual benefit in such form as shall
be required by law and/or appropriate.

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               4.   (a) KEC-NJ shall, after the preparation of each Payroll,
invoice IPC on a weekly basis for all appropriate payments for labor
compensation and benefits related to Pooled Employees employed by IPC pursuant
to this Agreement.

                    (b) Invoices evidencing appropriate payments shall be paid
by IPC by wire transfer within one business day of receipt by IPC of such
invoice, time being of the essence. IPC shall pay to KEC-NJ a total fee of
$5,000 per month during the Term (or on a pro rata basis for any partial month
during the Term based on the proportion that the number of days in such partial
month bears to a 30-day calendar month) to be paid to KEC-NJ on the first
business day of each calendar month for services rendered during each such month
during the Term for maintaining such pooling arrangement and performing its
obligations related to all Pooled Employees represented by IBEW Local 164T and
as otherwise provided herein.

               5.   IPC agrees to obtain a standby letter of credit, effective
as of the date hereof, in the aggregate amount of $1.5 million with respect to
the payments of (a) KEC-NJ, pursuant to Section 3 of this Agreement, for labor
compensation and benefits related to Pooled Employees and (b) Kleinknecht
Electric Company, Inc. (NY) ("KEC-NY"), pursuant to Section 3 of the Amended and
Restated Labor Pool Agreement, dated the date hereof, between KEC-NY and IPC
(the "KEC-NY Labor Pool Agreement") for labor compensation and benefits related
to Pooled Employees (as such term is defined in the KEC-NY Labor Pool
Agreement).

               6.   IPC shall continue to be the employer of Pooled Employees
while engaged in IPC's work and IPC shall continue to be solely responsible for
the direction of its own work and for the performance of all work undertaken by
the Pooled Employees while engaged in its

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work, and shall, at its own cost and expense, obtain and maintain customary
insurance coverage consistent with prior practice, which insurance shall name
KEC-NJ as an additional insured.

               7.   In this pooling arrangement, IPC specifically acknowledges
that it will comply with all legal requirements relating to the terms and
conditions of employment of any Pooled Employee employed pursuant to this
pooling arrangement, including, without limitation, the applicable provisions of
OSHA, the Fair Labor Standards Act, the Fair Employment Practices law and the
Equal Pay Act. In addition, IPC agrees not to discriminate against any employee
or applicant for employment because of race, creed, color, sex, affectional
preference, or national origin. IPC shall take affirmative action to afford
equal employment opportunities without such discrimination. Such action shall be
taken with reference to recruitment, employment, job assignment, promotion,
demotion, transfer, layoff, termination, rates of pay and other forms of
compensation and selection for training, including apprenticeship and on-the-job
training.

               8.   To the maximum extent permitted by law, IPC hereby assumes
and agrees to indemnify and hold KEC-NJ harmless against the entire
responsibility and liability for fines, penalties, and any and all damage
(direct and consequential) and injury (including death) of any kind or nature
whatsoever, to all persons, whether or not employees of KEC-NJ or IPC, and all
property, tangible and intangible, and damage thereto, caused by, resulting from
or arising out of, or in connection with

                    (a)  the information supplied hereunder by IPC;

                    (b)  the work performed by its employees, including any
                         Pooled Employees for IPC as provided hereunder;

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                    (c)  any occurrence which happens in or about the area where
                         the IPC work is performed and related to the
                         performance of work for IPC by the Pooled Employees as
                         provided hereunder; and

                    (d)  any breach of the obligations of IPC under this
                         Agreement by IPC.

Excluded from IPC's responsibility and liability shall be such fines, penalties
and other damage caused by KEC-NJ's negligence or breach hereof, or any claim
related to the work performed by KEC-NJ with its employees, including, without
limitation, any Pooled Employee to the extent that any such Pooled Employee is
performing services for KEC-NJ.

               9.   To the maximum extent permitted by law, KEC-NJ hereby
                    assumes and agrees to indemnify and hold IPC harmless
                    against the entire responsibility and liability for fines,
                    penalties, and any and all damage (direct and consequential)
                    and injury (including death) of any kind or nature
                    whatsoever, to all persons, whether or not employees of IPC
                    or KEC-NJ, and all property, tangible and intangible, and
                    damage thereto, caused by or resulting from or arising out
                    of, or in connection with the following:

                    (a)  the information supplied hereunder by KEC-NJ;

                    (b)  the work performed by the employees of KEC-NJ,
                         including, without limitation, any Pooled Employee to
                         the extent that any such Pooled Employee is performing
                         services for KEC-NJ;

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                    (c)  any occurrences which happen in or about the area where
                         KEC-NJ work is performed and related to the performance
                         of work for KEC-NJ by its employees;

                    (d)  any breach of the obligations of KEC-NJ under this
                         Agreement by KEC-NJ.

Excluded from KEC-NJ's responsibility and liability shall be such fines,
penalties and other damage caused by IPC's negligence or breach hereof or any
claim related to the work performed for IPC by Pooled Employees employed
hereunder.

            10. (a) IPC shall indemnify, defend and hold harmless, to the
fullest extent permitted under applicable law, the individual shareholders of
KEC-NJ (for purposes of this Agreement, collectively referred to as the "KEC-NJ
Indemnitees") from and against each Loss that arises from a reduction in the
value of the capital stock of such KEC-NJ Indemnitees because of a final
determination that the KEC-NJ Indemnitees are subject to multiemployer pension
plan withdrawal liability under Title IV of the Employee Retirement Income
Security Act of 1974, as amended (and the rules and regulations promulgated
thereunder) ("ERISA"), due solely to actions taken by IPC, including, without
limitation, IPC's failure, in whole or in part, to employ members of Local 164T,
or the termination or breach by IPC of this Agreement (it being understood that
such reduction in the value of such capital stock shall be deemed not to have
occurred if and to the extent that any such withdrawal liability shall have been
satisfied by IPC); provided, however, that the maximum amount of Losses for
which IPC shall have an obligation to indemnify under this Agreement and the
KEC-NY Labor Pool Agreement shall not exceed $5 million in the aggregate (the
"Cap"). All Losses arising from this Agreement that exceed the

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Cap shall be the sole responsibility of the KEC-NJ Indemnitees. For purposes of
this Section, "Losses" means any actual losses, damages, liabilities, costs or
expenses (including reasonable attorneys' fees and disbursements), judgments,
fines, penalties, and amounts paid in settlement; it being expressly understood
that Losses shall not include any fines, penalties, interest payments,
attorney's fees and disbursements, court costs or liquidated damages assessed as
a result of any failure of KEC-NJ to comply with the requirements of ERISA or
cooperate with IPC in compromising or defending such Loss in a timely and
reasonable manner (unless such fines, penalties, interest payments, attorney's
fees and disbursements, court costs or liquidated damages are due to IPC's
failure to make payments under this Section 10(a) in a timely manner).
Notwithstanding anything to the contrary contained in this Agreement, the
obligations of IPC to indemnify the KEC-NJ Indemnitees under this Section 10
shall terminate on the date on which the statute of limitations under applicable
law expires with respect to any applicable claim for a Loss hereunder. KEC-NJ
hereby represents and warrants to IPC that, other than Richard Kleinknecht,
Peter Kleinknecht and their respective children and Joe Iadanza and Joe
Lombardi, there are no owners of capital stock of KEC-NJ.

                        (b) Promptly after receipt by the KEC-NJ Indemnitees of
notice of any demand, claim or circumstance received by the KEC-NJ Indemnitees
on or after the date on which this Agreement became effective that, with or
without the lapse of time, the KEC-NJ Indemnitees have reason to believe may
result in any such Losses described in Section 10(a), the KEC-NJ Indemnitees
shall give notice thereof to IPC, which notice shall describe such demand, claim
or circumstance in reasonable detail and shall indicate the amount (estimated,
if necessary) of the Losses that have been or may be suffered by the KEC-NJ
Indemnitees. To the extent any

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such demand, claim or circumstance relates to Losses within the Cap, IPC shall
have the exclusive right to compromise or defend, by its own counsel, any such
demand, claim or circumstance and all fees and expenses related thereto shall be
borne by IPC. The KEC-NJ Indemnitees shall cooperate in the compromise of, or
defense against, such demand, claim or circumstance and shall make available to
IPC and its counsel any books, records or other documents within its control
that are necessary or appropriate for such compromise or defense.

                  11. The term of this Agreement (the "Term") shall be for a
period of twenty years from the date hereof, except that this Agreement may be
terminated as provided below:

                           (a)      IPC may terminate this Agreement at any
                                    time, with or without cause, upon ninety
                                    days' prior notice to KEC-NJ.

                           (b)      Either party may terminate this Agreement
                                    upon thirty (30) days' notice upon the
                                    happening of any of the following
                                    conditions:

                                    (i)      In the event of IPC's failure to
                                             reimburse KEC-NJ for Payroll and
                                             such failure continues for 3
                                             business days after IPC's actual
                                             receipt of KEC-NJ's written notice
                                             of such failure to pay;

                                    (ii)     In the event of a material default
                                             by the other party in the
                                             performance of its obligations
                                             hereunder, which default is not
                                             cured within ten days after the
                                             giving of written notice thereof;

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                                    (iii)    In the event the other party files
                                             a voluntary petition under the
                                             Bankruptcy Code, or for other
                                             debtor or insolvency relief;

                                    (iv)     In the event Local 164T IBEW
                                             withdraws its consent to or objects
                                             to the continuation of the pooling
                                             arrangement.

                  The termination or expiration of this Agreement under this
Section or under Section 14 shall not affect the rights and obligations
previously accrued.

                  The foregoing notwithstanding, this Agreement may be
terminated by either party on 90 days' prior notice without cost or penalty in
the event KEC-NJ shall determine to cease those operations which require that it
maintain a collective bargaining agreement.

                  12. Any notice required under this Agreement shall be in
writing and shall be served by certified mail, return receipt requested,
directed to the parties, as follows:

                  IF TO KEC-NJ:

                          Kleinknecht Electric Company, Inc. (NJ)
                          202 Rutgers Street
                          Maplewood, NJ 07040
                          Attention: Chairman or President

                  IF TO IPC:

                          IPC Information Systems, Inc.
                          88 Pine Street
                          New York, NY 10005
                          Attention: Chairman and General Counsel

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Notices otherwise validly given shall be effective two days after the mailing
notwithstanding the date of actual receipt, or the failure or refusal of a party
to sign the return receipt. The address of either party may be changed by such
party giving notice to the other.

                  13. This is an agreement which is intended to be applicable
solely to the sharing of a common pool of skilled labor. By virtue of this
pooling agreement, the parties hereto do not intend to create any partnership or
joint venture and neither party shall have any interest in the other party's
work, business or opportunities. It is further agreed that by virtue of this
pooling agreement KEC-NJ is not to be deemed or held out to be a subcontractor
of IPC with regard to IPC's work unless otherwise agreed to in writing by the
parties.

                  14. IPC agrees during the term of this Agreement to be bound
by industry-wide modifications and extensions of the KEC-NJ collective
bargaining agreement, provided that no such modification or extension limits the
continued use or benefit of this Agreement. Any modifications of the KEC-NJ
collective bargaining agreement which are individually bargained with Local 164T
shall be first subject to prior consultation with IPC to the extent that such
modifications affect IPC and its Pooled Employees and/or the continued use or
benefit of this Agreement. IPC shall have the right to terminate this Agreement
in the event that any modifications of the collective bargaining agreement
between KEC-NJ and Local 164T adversely affect IPC's continued use of the rights
under this Agreement or the substantive and/or economic benefits provided
therein. Such right to terminate by IPC shall be exercised by written notice to
KEC-NJ within 30 days after the later to occur of (a) receipt of written notice
by IPC of such modifications, (b) the applicable parties have agreed to such
modifications or (c) such modifications have become effective.

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                  15. In the event that an arbitration or legal proceeding is
initiated between KEC-NJ and Local 164T, then, to the extent that such
proceeding affects the IPC employees or IPC's rights or obligations hereunder,
IPC shall be given notice of the filing of such grievance or legal proceeding in
accordance with the notice provisions hereof and shall be given the opportunity
to participate in and defend its interests. If such notice and opportunity are
provided, IPC shall be bound by the determination made in such proceeding as if
IPC were a party.

                  16. Except with regard to Local 164T IBEW and the Trustees of
the affiliate Local 164T Fringe Benefit Funds, this Agreement is not intended to
create any rights in any person, firm or corporation not a party to this
Agreement.

                  17. The rights and obligations of this Agreement are not
assignable. In the event of any merger or consolidation of either party, or upon
the appointment of a receiver for the property of either of the parties hereto,
this Agreement shall, at the option of the other party, immediately terminate.

                  18. The failure to insist upon strict compliance with any of
the terms, covenants or conditions hereof shall not be deemed a waiver of such
term, covenant or condition. A waiver of any provision must be made in writing
and signed by the party against whom its enforcement is sought. A waiver at any
one or more times shall not be deemed a waiver at any other time or times.

                  19. A determination that any provision of this Agreement is
invalid shall not affect the validity or enforceability of any other provision.

                  20. This Agreement contains the entire understanding of the
parties relating to the subject matter hereof and supersedes all prior
agreements relating to the subject matter

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hereof. No modifications of this Agreement shall be valid unless made in writing
and signed by the parties.

                  21. This Agreement shall be governed by and construed pursuant
to the laws of the State of New York as an agreement made and performed in the
State of New York, without regard to any principle of conflicts of law that
would cause the application of the laws of any jurisdiction other than the State
of New York.

                  22. It is a condition precedent to the effectiveness of this
Agreement that the "Merger" under and as defined in the Agreement and Plan of
Merger, dated the date hereof, by and between Arizona Acquisition Corp. and IPC,
shall have been consummated.

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                  IN WITNESS WHEREOF, the parties hereto have caused this
Agreement to be signed by their duly authorized officers the day and year first
above written.

                                   KLEINKNECHT ELECTRIC COMPANY, INC. (NJ)

                                   By: /s/ Richard P. Kleinknecht
                                      ------------------------------
                                        Richard P. Kleinknecht, President

                                   IPC INFORMATION SYSTEMS, INC.

                                   By: /s/ S.T. Clontz
                                      ------------------------------
                                        S.T. Clontz, President

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