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                                [COMDISCO LOGO]

                         A TECHNOLOGY SERVICES COMPANY
                                                               
MASTER LEASE AGREEMENT dated          July 27, 1998               by and between
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COMDISCO, INC. ('Lessor') and    FiberNet Telecom Group, Inc.        ('Lessee').
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IN CONSIDERATION of the mutual agreements described below, the parties agree as
follows (all capitalized terms are defined in Section 14.13):

 1.  PROPERTY LEASED.

     Lessor leases to Lessee all of the Equipment described on each Schedule. In
the event of a conflict, the terms of a Schedule prevail over this Master Lease.

 2.  TERM.

     On the Commencement Date Lessee will be deemed to accept the Equipment,
will be bound to its rental obligations for each item of Equipment and the term
of a Schedule will begin and continue through the Initial Term and thereafter
until terminated by either party upon prior written notice received during the
Notice Period. No termination may be effective prior to the expiration of the
Initial Term.

 3.  RENT AND PAYMENT.

     Rent is due and payable in advance, in immediately available funds, on the
first day of each Rent. Interval to the payee and at the location specified in
Lessor's invoice. Interim Rent is due and payable when invoiced, if any payment
is not made when due, Lessee will pay interest at the Overdue Rate.

 4.  Selection and Warranty and Disclaimer of Warranties.

     4.1  Selection. Lessee acknowledges that it has selected the Equipment and
disclaims any refinance upon statements made by the Lessor.

     4.2  Warranty and Disclaimer of Warranties. Lessor warrants to Lessee that,
so long as Lessee is not in default, Lessor will not disturb Lessee's quiet and
peaceful possession, and unrestricted use of the Equipment. To the extent
permitted by the manufacturer, Lessor assigns to Lessee during the term of the
Schedule any manufacturer's warranties for the Equipment LESSOR MAKES NO OTHER
WARRANTY. EXPRESS OR IMPLIED AS TO ANY MATTER WHATSOEVER, INCLUDING, WITHOUT
LIMITATION, THE MERCHANTABILITY OF THE EQUIPMENT OR ITS FITNESS FOR A PARTICULAR
PURPOSE. Lessor is not responsible for any liability, claim, loss, damage or
expense of any kind (including strict liability in part) caused by the Equipment
except for any loss or damage caused by the negligent acts of Lessor. In no
event is Lessor responsible for special, incidental or consequential damages.  
 
 5.  TITLE AND ASSIGNMENT.

     5.1  Title. Lessee holds the Equipment subject and subordinate to the
rights of the Owner, Lessor, any Assignee and any Secured Party. Lessee
authorizes Lessor, as Lessee's agent, to prepare, execute and file in Lessee's
name precautionary Uniform Commercial Code financing statement showing the
interest of the Owner, Lessor, and any Assignee or Secured Party in the
Equipment and to insert serial numbers in Schedules as appropriate. Except as
provided in Sections 5.2 and 7.2, Lessee will, at its expense, keep the
Equipment free and clear from any liens or encumbrances of any kind (except any
caused by Lessor) and will indemnify and hold Lessor, Owner, any Assignee and
Secured Party harmless from and against any loss caused by Lessee's failure to
do so.

     5.2  Relocation or Sublease. Upon prior written notice. Lessee may relocate
Equipment to any location within the continued United States provided (i) the
Equipment will not be used by an entity exempt from federal income tax and (ii)
all additional costs (including any administrative fees, additional taxes and
insurance coverage) are reconciled and promptly paid by Lessee.

     Lessee may sublease the Equipment upon the reasonable consent of the Lessor
and the Secured Party. Such consent to sublease will be granted if: (i) Lessee
meets the relocation requirements set out above, (ii) the sublease is expressly
subject and subordinate to the terms of the Schedule, (iii) Lessee assigns its
rights in the sublease to Lessor and the Secured Party as additional collateral
and security, (iv) Lessee's obligation to maintain and insure the Equipment is
not altered, (v) all financing statements required to continue the Secured
Party's prior perfected security interest are filed, and (vi) the sublease is
not to a leasing entity affirmed with the manufacturer of the Equipment
described on the Schedule. Lessor acknowledges Lessee's right to sublease for a
term which extends beyond the expiration of the initial Term. If Lessee
subleases the Equipment for a term extending beyond the expiration of such
initial Term of the applicable Schedule. Lessee shall remain obligated upon the
expiration of the Initial Term to return such Equipment, or, at Lessor's sole
discretion to (i) return Like Equipment or (ii) negotiate a mutually acceptable
lease extension or purchase. If the parties cannot mutually agree upon the terms
of an extension or purchase, the term of the Schedule will extend upon the
original terms and conditions until terminated pursuant to Section 2.

     No relocation or sublease will relieve Lessee from any of its obligations
under this Master Lease and the applicable Schedule.

     5.3  Assignment by Lessee. The terms and conditions of each Schedule have
been fixed by Lessor. In order to permit Lessor to sell another assign of
transfer its 
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interest or grant a security interest in each Schedule and/or the Equipment to 
a Secured Party or Assignee. In that event the term Lessor will mean the 
Assignee and any Secured Party. However, any assignment, sale, or other 
transfer by Lessor will not relieve Lessor of its obligations to Lessee and will
not materially change Lessee's duties or materially increase the burdens or 
risks imposed on Lessee. The Lessee consents to and will acknowledge such 
assignments in a written notice given to Lessee. Lessee also agrees that:

     (a)  The Secured Party will be entitled to exercise all of Lessor's rights,
          but will not be obligated to perform any of the obligations of Lessor.
          The Secured Party will not disturb Lessee's quiet and peaceful
          possession and unrestricted use of the Equipment so long as Lessee is
          not in default and the Secured Party continues to receive all Rent
          payable under the Schedule;

     (b)  Lessee will pay all Rent and all other amounts payable to the Secured
          Party, despite any defense or claim which it has against Lessor.
          Lessee reserves its right to have recourse directly against Lessor for
          any defense or claim; and

     (c)  Subject to and without impairment of Lessee's leasehold rights in the
          Equipment, Lessee holds the Equipment for the Secured Party to the
          extent of the Secured Party's rights in that Equipment.

 6.  NET LEASE AND TAXES AND FEES.

     6.1  Net Lease. Each Schedule constitutes a net lease. Lessee's obligation
to pay Rent and all other amounts is absolute and unconditional and is not
subject to any abatement, reduction, set-off, defense, counterclaim,
interruption, deferment of recoupment for any reason whatsoever.

     6.2  Taxes and Fees. Lessee will pay when due or reimburse Lessor for all
taxes, fees or any other charges (together with any related interest or
penalties not arising from the negligence of Lessor) accrued for or arising
during the term of each Schedule against Lessor, Lessee or the Equipment by any
governmental authority (except only Federal, state and local taxes on the
capital or the net income of Lessor). Lessor will file all personal property tax
returns for the Equipment and pay all property taxes due. Lessee will reimburse
Lessor for property taxes within thirty (30) days of receipt of an invoice.

 7.  CARE, USE AND MAINTENANCE, ATTACHMENTS AND RECONFIGURATIONS AND INSPECTION 
     BY LESSOR.

     7.1  Care, Use and Maintenance. Lessee will maintain the Equipment in good
operating order and appearance, protect the Equipment from deterioration, other
than normal wear and tear, and will not use the Equipment for any purpose other
than that for which it was designed. If commercially available, Lessee will
maintain in force a standard maintenance contract with the manufacturer of the
Equipment, or another party acceptable to Lessor, and upon request will provide
Lessor with a complete copy of that contract. If Lessee has the Equipment
maintained by a party other than the manufacturer, Lessee agrees to pay any
costs necessary for the manufacturer to bring the Equipment to then current
release, revision and engineering change levels, and to re-certify the Equipment
as eligible for manufacturer's maintenance at the expiration of the lease term.
The lease term will continue upon the same terms and conditions until
recertification has been obtained.

     7.2  Attachments and Reconfigurations. Upon prior written notice to Lessor,
Lessee may reconfigure and install Attachments on the Equipment. In the event of
such a Reconfiguration or Attachment, Lessee shall, upon return of the
Equipment, at it expense, restore the Equipment to the original configuration
specified on the Schedule in accordance with the manufacturer's specifications
and in the same operating order, repair and appearance as when installed (normal
wear and tear excluded). If any parts are removed from the Equipment during the
Reconfiguration or Attachment, the restoration will include, at Lessee's option,
the installation of either the original removed parts or Like Parts.
Alternatively, with Lessor's prior written consent which will not be
unreasonably withheld, Lessee may return the Equipment with any Attachment or
upgrade. If any parts of the Equipment are removed during a Reconfiguration or
Attachment, Lessor may require Lessee to provide additional security,
satisfactory to the Lessor. In order to ensure performance of Lessee's
obligations set forth in this subsection. Neither Attachments nor parts
installed on Equipment in the course of Reconfiguration shall be accessions to
the Equipment.

     However, if the Reconfiguration or Attachment (i) adversely affects
Lessor's tax benefits relating to the Equipment; (ii) is not capable of being
removed without causing material damage to the Equipment; or (iii) if at the
time of the Reconfiguration or Attachment the manufacturer does not offer on a
commercial basis a means for the removal of the additional items; then such
Reconfiguration or

     Attachment is subject to the prior written consent of Lessor.

     7.3  Inspection by Lessor. Upon request, Lessee, during reasonable business
hours and subject to Lessee's security requirements, will make the Equipment and
its related log and maintenance records available to Lessor for inspection. 
                                       
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 8.  REPRESENTATIONS AND WARRANTIES OF LESSEE.

     Lessee represents and warrants that for the Master Lease and each Schedule:

         (a) The execution, delivery and performance of the Lessee have been
             duly authorized by all necessary corporate action;

         (b) The individual executing was duly authorized to do so;

         (c) The Master Lease and each Schedule constitute legal, valid and
             binding agreements of the Leases enforceable in accordance with
             their terms, and

         (d) The Equipment is personal property and when subjected to use by the
             Lessee will not be or become fixtures under applicable law.

 9.  DELIVERY AND RETURN OF EQUIPMENT.
     
     Lessee assumes the full expense of transportation and in-transit insurance
to Lessee's premises and for installation of the Equipment. Upon expiration or
termination of each Schedule, Lessee will, at Lessor's instructions and at
Lessee's expense (including transportation and in-transit insurance), have the
Equipment reinstalled, audited by the manufacturer, packed and shipped in
accordance with the manufacturer's specifications and returned to Lessor in the
same operating order, repair and appearance as when installed (ordinary wear and
tear excluded), to a location within the continental United States as directed
by Lessor. All items returned to Lessor in addition to the Equipment become
property of Lessor.

10.  LABELLING.

     Upon request, Lessee will mark the Equipment indicating Lessor's interest.
Lessee will keep all Equipment free from any other marketing or labeling which
might be interpreted as a claim of ownership.

11.  INDEMNITY.

     Lessee will indemnify and hold Lessor, any Assignee and any Secured Party
harmless from and against any and all claims, costs, expenses, damages and
liabilities, including reasonable attorney's fees, arising out of the ownership
(for strict liability in tort only), selection, possession, leasing, operation,
control, use, maintenance, delivery, return or other disposition of the
Equipment. However, Lessee is not responsible to a party indemnified hereunder
for any claims, costs, expenses, damages and liabilities occasioned by the
negligent acts of such indemnified party. Lessee agrees to carry bodily injury
and property damage liability insurance during the term of the Master Lease in
amounts and against risks customarily insured against by the Lessee on equipment
owned by it. Any amounts received by Lessor under that insurance will be
credited against Lessee's obligations under this Section.

12.  RISK OF LOSS.

     12.1  Lessee's Risk of Loss. If the Schedule indicates that the Lessee has
responsibility for the risk of loss of the Equipment, then the following terms
will apply:

     Effective upon delivery and until the Equipment is returned, Lessee
relieves Lessor of responsibility for all risks of physical damage to or loss or
destruction of the Equipment. Lessee will carry casualty insurance for each item
of Equipment in an amount not less than the Casualty Value. All policies for
such insurance will name the Lessor and any Secured Party as additional insured
and as loss payee, and will provide for at least thirty (30) days prior written
notice to the Lessor of cancellation or expiration. The Lessee will furnish
appropriate evidence of such insurance.

     Lessee shall promptly repair any damaged item of Equipment unless such
Equipment has suffered a Casualty Loss. Within fifteen (15) days of a Casualty
Loss, Lessee will provide written notice of that loss to Lessor and Lessee will,
at Lessor's option, either (a) replace the item of Equipment with Like Equipment
and marketable title to the Like Equipment will automatically vest in Lessor or
(b) pay the Casualty Value and after that payment and the payment of all other
amounts due and owing, Lessee's obligation to pay further Rent for the item of
Equipment will cease. 

     12.2  Lessor's Risk of Loss. If the Schedule indicates that the Lessor has
responsibility for the risk of loss of the Equipment, then the following terms
will apply:
  
     Effective upon delivery and throughout the Initial Term of a Schedule and
any extension, Lessor agrees to insure the Equipment against physical damage to
or loss or destruction due to external cause as specified by the terms of
Lessor's then current insurance policy. Lessor relieves Lessee of responsibility
for physical damage to or loss or destruction of Equipment reimbursed by that
insurance. Lessee will give Lessor prompt notice of any damage, loss or
destruction to any item of Equipment and Lessor will determine within fifteen
(15) days of his receipt of that notice whether the item has suffered a Casualty
Loss.

     If any item of Equipment suffers damage or a Casualty Loss which is
reimbursable under Lessor's insurance, upon payment by Lessee of Lessor's
deductible, Lessor will: (i) (for damaged Equipment) arrange and pay for the
    
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repair of any damaged Item of Equipment or (ii) (for any Casualty Loss) at
Lessor's option either replace the Item of Equipment with Like Equipment or upon
payment of all other amounts due by Lessee terminate the relevant Schedule as it
relates to that Item of Equipment.

     If any Item Equipment settles damage or a Casualty Loss which is not
reimbursable under Lessor's insurance, then Lessee will comply with the
provisions of the last paragraph of Section 12.1 regarding repair, replacement
or payment of Casualty Value.

     If Lessor fails to maintain insurance coverage as required by this
subsection 12.2 Lessee will assume such risk of loss and, at the request of any
Assignee or Secured Party, will promptly provide insurance coverage. This
paragraph does not relieve lessor of its obligations to maintain coverage of the
Equipment.

13.  DEFAULT, REMEDIES AND MITIGATION.

     13.1  Default. The occurrence of any one or more of the following Events of
Default constitutes a default under a Schedule:

     (a)  Lessee's failure to pay Rent or other amounts payable by Lessee when
          due if that failure continues for ten (10) days after written notice;
          or

     (b)  Lessee's failure to perform any other item or condition of the
          Schedule or the material inaccuracy of any representation or warranty
          made by the Lessee in the Schedule or in any document or certificate
          furnished to the Lessor hereunder if that failure or inaccuracy
          continues for fifteen (15) days after written notice; or

     (c)  An assignment by Lessee for the benefit of its creditors, the failure
          by Lessee to pay its debts when due, the insolvency of Lessee, the
          filing by Lessee or the filing against Lessee of any petition under
          any bankruptcy or insolvency law or for the appointment of a trustee
          or other officer with similar powers, the adjudication of Lessee as
          insolvent, the liquidation of Lessee, or the taking of any action for
          the purpose of the foregoing; or

     (d)  The occurrence of an Event of Default under any Schedule or other
          agreement between Lessee and Lessor or its Assignee or Secured Party.

     13.2  Remedies. Upon the occurrence of any of the above Events of Default,
Lessor, at the option, may:

     (a)  enforce Lessee's performance of the provisions of the applicable
          Schedule by appropriate court action in law or in equity:
   
     (b)  recover from Lessee any damages and or expenses, including Default
          Costs;

     (c)  with notice and demand, recover all sums due and accelerate and
          recover the present value of the remaining payment stream of all Rent
          due under the defaulted Schedule (discounted at the same rate of
          interest at which such defaulted Schedule was discounted with a
          Secured Party plus any prepayment fees charged to Lessor by the
          Secured Party or, if there is no Secured Party, then discounted at 8%)
          together with all Rent and other amounts currently due as liquidated
          damages and not as a penalty;

     (d)  with notice and process of law and in compliance with Lessee's
          security requirements. Lessor may enter Lessee's premises to remove
          and repossess the Equipment without being liable to Lessee for damages
          due to the repossession, except those resulting from Lessor's, its
          assignees', agents' or representatives' negligence; and

     (e)  pursue any other remedy permitted by law or equity.

     The above remedies, in Lessor's discretion and to the extent permitted by
law, are cumulative and may be exercised successively or concurrently.

     13.3  Mitigation. Upon return of the Equipment pursuant to the terms of
Section 13.2, Lessor will use its best efforts in accordance with its normal
business procedures (and without obligation to give any priority to such
Equipment) to mitigate Lessor's damages as described below. EXCEPT AS SET FORTH
IN THIS SECTION, LESSEE HEREBY WAIVES ANY RIGHTS NOW OR HEREAFTER CONFERRED BY
STATUTE OR OTHERWISE WHICH MAY REQUIRE LESSOR TO MITIGATE ITS DAMAGES OR MODIFY
ANY OF LESSOR'S RIGHTS OR REMEDIES STATED HEREIN. Lessor may sell, lease or
otherwise dispose of all or any part of the Equipment at a public or private
sale for cash or credit with the privilege of purchasing the Equipment. The
proceeds from any sale, lease or other disposition of the Equipment are defined
as either:

     (a)  if sold or otherwise disposed of, the cash proceeds less the Fair
          Market Value of the Equipment at the expiration of the initial Term
          less the Default Costs; or

     (b)  if leased, the present value (discounted at three points over the
          prime rate as referenced in the Wall Street Journal at the time of the
          mitigation) of the rentals for a term not to exceed the initial Term,
          less the Default Costs.

     Any proceeds will be applied against liquidated damages and any other sums
due to Lessor from Lessee. However, Lessee is liable to Lessor for, and Lessor
may recover, the amount by which the proceeds are less than the liquidated
damages and other sums due to Lessor from Lessee.
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14.  ADDITIONAL PROVISIONS.

     14.1  Entire Agreement. This Master Lease and associated Schedules
supersede all other oral or written agreements or understandings between the
parties concerning the Equipment including, for example, purchase orders. ANY
AMENDMENT OF THIS MASTER LEASE OR A SCHEDULE, MAY ONLY BE ACCOMPLISHED BY A
WRITING SIGNED BY THE PARTY AGAINST WHOM THE AMENDMENT IS SOUGHT TO BE ENFORCED.

     14.2  No Waiver. No action taken by Lessor or Lessee shall be deemed to
constitute a waiver of compliance with any representation, warranty or covenant
contained in this Master Lease or a Schedule. The waiver by Lessor or Lessee of
a breach of any provision of this Master Lease or a Schedule will not operate or
be construed as a waiver of any subsequent breach.

     14.3  Binding Nature. Each Schedule is binding upon, and inures to the
benefit of Lessor and its assigns. LESSEE MAY NOT ASSIGN ITS RIGHTS OR
OBLIGATIONS.

     14.4  Survival of Obligations. All agreements, obligations including, but
not limited to those arising under Section 6.2, representations and warranties
contained in this Master Lease, any Schedule or in any document delivered in
connection with those agreements are for the benefit of Lessor and any Assignee
or Secured Party and survive the execution, delivery, expiration or termination
of this Master Lease.

     14.5  Notices. Any notice, request or other communication to either party
by the other will be given in writing and deemed received upon the earlier of
actual receipt or three days after mailing if mailed postage prepaid by regular
or airmail to Lessor (to the attention of ""Lease Administrator'') or Lessee, at
the address set out in the Schedule or, one day after it is sent by courier or
facsimile transmission if receipt is verified by the receiving party.

     14.6  Applicable Law. THIS MASTER LEASE HAS BEEN, AND EACH SCHEDULE WILL
HAVE BEEN MADE, EXECUTED AND DELIVERED IN THE STATE OF ILLINOIS AND WILL BE
GOVERNED AND CONSTRUED FOR ALL PURPOSES IN ACCORDANCE WITH THE LAWS OF THE STATE
OF ILLINOIS WITHOUT GIVING EFFECT TO CONFLICT OF LAW PROVISIONS. NO RIGHTS OR
REMEDIES REFERRED TO IN ARTICLE 2A OF THE UNIFORM COMMERCIAL CODE WILL BE
CONFERRED ON LESSEE UNLESS EXPRESSLY GRANTED IN THIS MASTER LEASE OR A SCHEDULE.

     14.7  Severability. If any one or more of the provisions of this Master
Lease or any Schedule is for any reason held invalid, illegal or unenforceable,
the remaining provisions of this Master Lease and any such Schedule will be
unimpaired, and the invalid, illegal or unenforceable provision replaced by a
mutually acceptable valid, legal and enforceable provision that is closest to
the original intention of the parties.

     14.8  Counterparts. This Master Lease and any Schedule may be executed in
any number of counterparts, each of which will be deemed an original, but all
such counterparts together constitute one and the same instrument. If Lessor
grants a security interest in all or any part of a Schedule, the Equipment or
sums payable thereunder, only that counterpart Schedule marked ""Secured Party's
Original'' can transfer Lessor's rights and all other counterparts will be
marked ""Duplicate''.

     14.9  Nonspecified Features and Licensed Products. If the Equipment is
supplied from Lessor's inventory and contains any features not specified in the
Schedule, Lessee grants Lessor the right to remove any such features. Any
removal will be performed by the manufacturer or another party acceptable to
Lessee, upon the request of Lessor, at a time convenient to Lessee, provided
that Lessee will not unreasonably delay the removal of such features.

     Lessee shall obtain no title to Licensed Products which will at all times
remain the property of the owner of the Licensed Products. A license from the
owner may be required and it is Lessee's responsibility to obtain any required
license before the use of the Licensed Products. Lessee agrees to treat the
Licensed Products as confidential information of the owner, to observe all
copyright restrictions, and not to reproduce or sell the Licensed Products.

     14.10  Additional Documents. Lessee will, upon execution of this Master
Lease and as may be requested thereafter, provide Lessor with a secretary's
certificate of incumbency and authority and any other documents reasonably
requested by Lessor. Upon the execution of each Schedule with an aggregate Rent
in excess of $2,000,000, Lessee will provide Lessor with an opinion from
Lessee's counsel regarding the representations and warranties in Section 8.
Lessee will furnish, upon request, audited financial statements for the most
recent period.

     14.11  Electronic Communications. Each of the parties may communicate with
the other by electronic means under mutually agreeable terms.  
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     14.12  Lessor's Right to Match. Lessee's rights under Section 5.2 and 7.1
are subject to Lessor's right to match any sublease or upgrade proposed by a
third party. Lessee will provide Lessor with the terms of the third party offer
and Lessor will have three (3) business days to match the offer. Lessee shall
obtain such upgrade from or sublease the Equipment to Lessor if Lessor has
timely matched the third party offer.

     14.13  Definitions.
ASSIGNEE -- means an entity to whom Lessor has sold or assigned
its rights as owner and Lessor of Equipment.

ATTACHMENT -- means any accessory, equipment or device and the Installation
thereof that does not impair the original function or use of the Equipment and
is capable of being removed without causing material damage to the Equipment and
is not an accession to the Equipment.

CASUALTY LOSS -- means the irreparable loss or destruction of Equipment.

CASUALTY VALUE -- means the greater of the aggregate Rent remaining to be paid
for the balance of the lease term or the Fair Market Value of the Equipment
immediately prior to the Casualty Loss. However, if a Casualty Value Table is
attached to the relevant Schedule its terms will control.

COMMENCEMENT CERTIFICATE -- means the Lessor provided certificate which must be
signed by Lessee within ten days of the Commencement Date as requested by
Lessor.

COMMENCEMENT DATE -- is defined in each Schedule.

DEFAULT COSTS -- means reasonable attorney's fees and remarketing costs
resulting from a Lessee default or Lessor's enforcement of its remedies.

EQUIPMENT -- means the property described on a Schedule and any replacement for
that property required or permitted by this Master Lease or a Schedule but not
including any Attachment.

EVENT OF DEFAULT -- means the events described in Subsection 13.1.

FAIR MARKET VALUE -- means the aggregate amount which would be obtainable in an
arms-length transaction between an informed and willing buyer/user and an
informed and willing seller under no compulsion to sell.

INITIAL TERM -- means the period of time beginning on the first day of the first
full Rent Interval following the Commencement Date for all items of Equipment
and continuing for the number of Rent Intervals indicated on a Schedule.

INSTALLATION DATE -- means the day on which Equipment is installed and qualified
for a commercially available manufacturer's standard maintenance contract or
warranty coverage, if available.

INTERIM RENT -- means the pro-rate portion of Rent due for the period from the
Commencement Date through but not including the first day of the First full Rent
Interval included in the Initial Term.

LICENSED PRODUCTS -- means any software or other licensed products attached to
the Equipment.

LIKE EQUIPMENT -- means replacement Equipment which is lien free and of the same
model, type, configuration and manufacture as Equipment.

LIKE PART -- means a substituted part which is lien free and of the same
manufacturer and part number as the removed part, and which when installed on
the Equipment will be eligible for maintenance coverage with the manufacturer of
the Equipment.

NOTICE PERIOD -- means the time period described in a Schedule during which
Lessee may give Lessor notice of the termination of the term of that Schedule.

OVERDUE RATE -- means the lesser of 18% per year or the maximum rate permitted
by the law of the state where the Equipment is located.

OWNER -- means the owner of Equipment.

RECONFIGURATION -- means any change to Equipment that would upgrade or downgrade
the performance capabilities of the Equipment in any way.

RENT -- means the rent, including Interim Rent, Lessee will pay for each item of
Equipment expressed in a Schedule either as a specific amount or an amount equal
to the amount which Lessor pays for an Item of Equipment multiplied by a lease
rate factor plus all other amounts due to Lessor under this Master Lease or a
Schedule.

RENT INTERVAL -- means a full calendar month or quarter as indicated on a
Schedule.

SCHEDULE -- means an Equipment Schedule which incorporates all of the terms and
conditions of this Master Lease and, for purposes of Section 14.B its associated
Commencement Certificate(s).

SECURED PARTY -- means an entity to whom Lessor has granted a security interest
in a Schedule and reused Equipment for the purpose of securing a loan.
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IN WITNESS WHEREOF, the parties hereto have executed this Master Lease on or as 
of the day and year first above written.


FIBERNET TELECOM GROUP, INC.               COMDISCO, INC.,
as Lessee                                  as Lessor


By: [Name]                                 By: [Name]
    ------------------------------------       ---------------------------------


Title: Sr. VP Financial & Administration   Title: 
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