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                      [LETTERHEAD OF LE FROIS DEVELOPMENT]

THIS AGREEMENT OF LEASE, dated as of the 12th day of March, 1998, between
RICHARD R. LEFROIS, having an office and place of business located at 1020
Lehigh Station Road, Henrietta, New York, hereinafter described as "Landlord"
and Fibernet Telecom, Inc. a Corporation organized under the laws of the State
of Delaware, with an address of 121 Erie Canal Drive, Rochester, New York 14626,
hereinafter described as "Tenant".

                                   WITNESETH:

1. DESCRIPTION

Landlord hereby leases to Tenant and Tenant hereby rents from Landlord the
premises described on "Exhibit A" attached hereto, consisting of approximately
15,000 square feet of floor area located at 100 Town Centre Drive, Rochester,
New York 14623 (the "Premises").

2. TERM

(A). The term of this Lease (The "Lease Term") shall be seven (7) years, to
commence on July 1, 1998 and to end at midnight, June 30, 2005. In the event
Tenant shall elect to construct its own office space during the term of this
lease, or any extension, and shall use the services of Landlord as construction
contractor, Landlord agrees that the term of this lease shall end (and the
respective duties of the parties hereto shall terminate) when Tenant takes
beneficial occupancy of the new Premises construction by Landlord.

(B). The term "Lease Year" as used herein is defined to be a period of twelve
consecutive calendar months beginning July 1, 1998 of each year of the Lease
Term.

3. RENT

The rent during the term of this Lease shall be $110,000.00 annually, to be paid
in equal consecutive monthly installments of $9,166.67 in advance on the first
(1st) day of each month


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during the term hereof, without deduction, setoff or prior demand which rent
Tenant agrees to pay in lawful money of the United States, which shall be
legal tender in payment of all debts and dues, public and private, to the
Landlord, Mr. Richard R. LeFrois, P. 0. Box 92878, Department No. 102,
Rochester, New York 14692, or such other place as the Landlord may designate.

This Lease is granted and accepted upon the foregoing and upon the following
covenants and conditions and subject to the following restrictions, to all and
every one of which the parties consent; and each of the parties hereby expressly
covenants and agrees to keep, perform and observe all the terms, covenants and
conditions herein contained on its part to be kept, performed and observed.

4. USE

The Premises may be used and occupied exclusively by Tenant as a network center,
an office and warehouse. Tenant will not at anytime use or occupy the Premises
in violation of its approved use. No part of the Premises shall be occupied or
used by any persons for any purpose or in any manner so as to increase the
insurance risk or rates or prevent the obtaining of insurance; nor so that, in
accordance with any requirement or law or any public authority, the Landlord
shall be obligated, on account of the purpose or manner of said use or
occupation, to make any addition or alteration to or in the building. If, by
reason of Tenant's failure to comply with this provision, the fire insurance
rate at any time shall be higher than it otherwise would have been then Tenant
shall reimburse Landlord, as additional rent, for that part of all fire
insurance premiums thereafter paid by Landlord by reason or such violation by
Tenant.

5. LANDLORD'S REPAIRS

      Landlord Shall Maintain and Repair:

            1.    All Structural Elements of the Premises.

            2.    Exterior walls.

            3.    Roofs.

            4.    Major Repairs to the Pipes, Fixtures.

      Tenant is responsible for the maintenance of the appliances and equipment
      which includes the HVAC units. As long as damages have not been caused by
      tenant's failure to


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      maintain appliances and equipment properly, Landlord shall be responsible
      for major repairs or replacement to the appliances and equipment,
      including the HVAC equipment.

      As used herein, the term "major repairs" shall mean repairs costing more
      than Five Hundred Dollars, ($500.00) individually or aggregating more than
      One Thousand Dollars, ($1,000.00) in any lease year in respect of any one
      such system.

6. UTILITIES

      (A) Tenant shall pay, as additional rent, all charges for light, heat,
power, electric, gas, water, sewerage charges, pollution charges, Pure Water
charges, fuel charges and such other similar services furnished or used by
Tenant in connection with the Premises during the Lease Term.

      (B) Landlord agrees to install separate utility meters for the Premises.

7. REMEDIES OF TENANT REGARDING PROVISION OF SERVICES AND UTILITIES

No diminution or abatement of rent or other compensation shall be claimed or
allowed for inconvenience or discomfort arising from the making of ordinary
repairs or improvements to the building or to its appliances except in the event
that such repairs are necessitated (i) by any failure by Landlord to carry out
its duties to repair and maintain the Premises hereunder, or (ii) by the
negligent, reckless or intentional act of Landlord, it's assigns, agents,
employees or guests. However, to the extent that any part of the Premises is
unavailable to Tenant as a result of the necessity to comply with any law,
ordinance or order of a governmental authority, the rent shall be apportioned
ratably. In respect to the various "services", if any, herein expressly or
impliedly agreed to, be furnished by the Landlord to the Tenant, it is agreed
that there shall be no diminution or abatement of the rent, or any other
compensation, for interruption or curtailment of such "services" when such
interruption or curtailment shall be due to accident, alterations or repairs
reasonably or necessary to be made or to some other cause, not gross negligence
on the part of the Landlord. No such interruption or curtailment of any such
"services" shall be deemed a constructive eviction. Any required repairs,
alterations, etc., shall be done with reasonable dispatch.


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8. PREPARATION OF PREMISES

      Landlord's Improvements:

      (A).  Space to be divided into:

            Approximately 10,000 square feet of finished office space.

            Approximately 5,000 square feet of unfinished warehouse space.

      (B).  The finished office space to incorporate:

            1.    Office space to be open "bull pen".

            2.    The office area will have dropped ceilings with 2' x 4'
                  lay-ins and recessed lighting fixtures of sufficient candle
                  power to eliminate need of desk lighting

            3.    The office area will have nine (9) feet of drywall painted

            4.    Each office door will be equipped with different individual
                  locks and keys, but all locks "master Keyed" for the Branch
                  Manager only (including the door opening into the warehouse
                  area).

            5.    If Tenant desires window treatments, Tenant shall provide any
                  and all window treatments. Any interior window treatment shall
                  be per Tenants design, any exterior window treatment shall be
                  verticals to maintain a similar exterior appearance.

9. MAINTENANCE AND REPAIRS

Tenant (a) except as specifically set forth in section 5, shall, at the Tenant's
own expense, take good care of the Premises, and the pipes, fixtures,
appliances, equipment and appurtenances belonging thereto, and keep the same in
good order and repairs (if any) shall of comparable quality to the original
work; on default of Tenant to do such work, the Landlord may do it for Tenant's
account, and Tenant shall reimburse Landlord for the reasonable cost of such
repairs; (b) shall not cut or drill or otherwise deface or injure the building;
(c) shall not use or permit the use of the roof except as shall be expressly
permitted in writing by Landlord, including, without limitation, for the
installation thereon of any antenna, airlines, masts, or other radio or
television equipment; (d) shall not, without the Landlord's prior written
consent first obtained in each instance, permit any matter or thing to be
extended or projected from the window sash, window sill, cornice or fire escape
of the Premises; (e) shall, within thirty (30) days after the Landlord's demand
and submission to Tenant appropriate documentation thereof, pay to Landlord as


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additional rent hereunder, an amount equal to any increase, if any, in the
amount of the fire insurance premium applicable to the building for and during
the Demised term resulting from the Tenant's use and occupancy of the Premises
in violation of the use permitted in this Lease, or from the Tenant's failure to
comply with any requirements of law or the commercially reasonable
recommendation of Landlord's insurance carrier; (f) shall not, without the
Landlord's prior written consent first obtained in each instance which shall not
be unreasonably withheld, make alteration or addition to the electric wiring,
equipment, or appliances, including, without limitation, any heating, air
conditioning system, water systems, or gas pipe systems, or tap any mains or
pipes to supply water for refrigeration or air conditioning apparatus; (g) shall
not, without Landlord's prior written consent first obtained in each instance
which shall not be unreasonably withheld, make any alterations, decorations or
improvements in or to the Premises, provided however, Landlord's consent to
non-structural interior alterations or decorations shall not be unreasonably
withheld; (h) shall comply with all reasonable and uniform regulations and
orders of Landlord designated to promote the safety or good order of the
building; and (i) shall promptly discharge by filing the necessary bond, or
otherwise, any mechanic's lien or other lien filed against the Premises because
of any work or material done or furnished to the Tenant. All alterations,
additions or improvements made to the Premises by either party, including
railings, galleries, decorations, paneling and similar items, unless Landlord
shall otherwise elect in writing, shall become the property of Landlord and be
surrendered as part of the Premises at the expiration or earlier termination of
this Lease.

10. COVENANT AGAINST ASSIGNMENT AND SUBLETTING

      (A) Without the previous written consent of the Landlord, neither the
Tenant, nor the Tenant's legal representatives or successors in interest by
operation of law or otherwise, shall assign or mortgage this Lease, or sublet
the whole or any part of the Premises or any part thereof to be used by others.
Any consent by Landlord to any act of assignment or subletting shall be held to
apply only to the specific transaction thereby authorized. Such consent shall
not be construed as a waiver of the duty of Tenant, or the legal representatives
or assigns of Tenant, to obtain from the legal representatives or assigns of
Tenant, to obtain from Landlord consent to any other or subsequent assignment or
subletting, or as modifying or limiting the rights of Landlord under the
foregoing covenant by Tenant not to assign or sublet without such consent. Any
material violation of any provision of this Lease, whether by act or omission,
by any assignee, subtenant, or undertenant, or occupant shall be deemed a
violation of such provision by Tenant, it being the intention and meaning of the
parties hereto that Tenant shall assume and be liable to Landlord for any and
all acts and omissions of any and all assignees, sub-tenants and under-tenants
and occupants. If this Lease be assigned, the Landlord may, and is hereby
empowered to collect rent from the assignee if the Premises or any part thereof
be underlet or


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occupied by any person or Corporation other than Tenant. Landlord, in the event
of Tenant's default may, and is hereby empowered to, collect rent from the
undertenant or occupant; in either of such events, Landlord may apply the net
amount received by it to the rent herein reserved, and no such collection shall
be deemed a waiver of the covenant herein against assignment and underletting,
or the acceptance of the assignee, undertenant, or a release of the Tenant from
the further performance of the covenants herein contained on the part of the
Tenant.

      (B) Notwithstanding the provision of paragraph 10(A) hereof, the Tenant
may, without the Landlord's consent, assign this Lease to any parent, affiliated
or subsidiary corporation, provided such assignment does not relieve the
original Tenant of any liability hereunder.

11. RIGHT OF ENTRY

Tenant, during the term hereof, shall permit inspection upon reasonable prior
notice before entry of the demised Premises during reasonable business hours by
Landlord's agents or representatives, and by or on behalf of prospective
purchasers; and shall permit access by the Landlord, or Landlord's agents or
representatives during reasonable hours for the purpose of making repairs,
renovations or decorations.

12. COVENANT TO SURRENDER; REMOVAL OF PERSONAL PROPERTY

On the last day of the Lease Term or on the sooner termination thereof, Tenant
shall peaceably and quietly leave, surrender and yield up unto the Landlord all
and singular the Premises broom-clean and in good order and repair, ordinary
wear and tear and damage by fire, condemnation or other casualty as is insurable
under present or future standard forms of fire and extended coverage insurance
policies, excepted, together with all alterations, additions and improvements
which may have been made upon the Premises with Landlord's permission except
movable furniture or movable trade fixtures put in at the expenses of Tenant. If
the last day of the Lease Term falls on Sunday, this Lease shall expire on the
business day immediately preceding it. Tenant, on or before said date, shall
remove all its property from the Premises, and all property not so removed shall
be deemed abandoned by Tenant. If said Premises be not surrendered at the end of
the term, Tenant shall make good to Landlord all reasonable costs which Landlord
shall actually incure by reason thereof

13. FIRE OR CASUALTY DAMAGE

In case of damage to the Premises or the building of which the Premises are a
part by fire, or other casualty as is insurable under present or future standard
forms of fire and extended coverage insurance policies, Landlord, unless it
shall otherwise elect as hereinafter provided,


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shall repair the same with reasonable dispatch after written notice of damage.
If the Premises, or any part thereof, are damaged by fire, enemy action, or
other casualty to such an extent as to be rendered untenantable, but are,
nevertheless, repaired by Landlord, then the rent shall be abated to an extent
corresponding with the time during which and the extent to which said Premises
may have been untenantable. If such repairs, however, are delayed because of
Tenant's failure to adjust Tenant's own insurance claim, no reduction shall be
made beyond a reasonable time allowed for such adjustment. If the Landlord in
its exclusive discretion, shall decide, within a reasonable time after the
occurrence of any such fire, enemy action, or other casualty, to demolish,
rebuild or reconstruct the building, then, upon at least sixty (60) days written
notice given by Landlord to Tenant, this lease shall terminate on a date to be
specified in such notice as if that date had been originally fixed as the
expiration date of the Lease Term, and the rent shall be adjusted as of the time
of the occurrence of any such fire, enemy action, or other casualty. Tenant
shall give immediate notice to Landlord in case of fire or other casualty or in
the event of accidents to or defect in any fixtures or equipment of the
building. Landlord, for itself and its insurers, hereby releases Tenant with
respect to any liability (including that deriving from the fault or neglect of
Tenant, assignees, sub-tenants, its agents, employees or other persons under its
or their direction or control) which Tenant might otherwise have for any damage
to the building or the Premises by fire, explosion, or any other perils covered
by Landlord's insurance, occurring during the Lease Term. Whenever Landlord
elects to insure the Premises or the building against fire or other casualty
with an insurance company selected by Landlord, Landlord shall cause all
policies evidencing such insurance to include a provision permitting such
release of liability if such a provision is obtainable from such insurer at no
additional expense to Landlord. If such insurer will not include such a
provision in said policy, or if the inclusion of such provision in such policy
would involve an additional expense for Landlord, Landlord shall so advise
Tenant within a reasonable time. Where such a provision is obtainable from such
insurer and Tenant notifies Landlord in writing within a reasonable time
thereafter the Tenant desires Landlord to cause such a provision to be included
in such policy at the expense of Tenant, Landlord shall cause such a provision
to be included, and Tenant agrees to pay promptly all reasonable expenses
incurred by Landlord as a result of such inclusion.

In case Landlord shall fail to complete such repairs within ninety (90) days
from the date of such damage, the Tenant may at any time after such ninety (90)
day period give Landlord thirty (30) days notice in writing of termination of
this lease, then at the expiration of such thirty day period, this lease shall
terminate as completely as if that were the date fixed for expiration of the
term of this lease unless, Landlord shall have completed such repairs prior to
the expiration of such thirty day period.


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14. CONDEMNATION

If the whole or a substantial part of the Premises shall be taken for any public
or quasi-public use, under any statute or by right of eminent domain or private
purchase in lieu thereof by a public body vested with the power of eminent
domain, then, when possession shall be taken thereunder of the Premises, or any
part thereof, the term herein demised and all rights of Tenant hereunder shall
immediately cease and terminate, and the rent shall be adjusted as of the time
of such termination.

15. RELEASE FROM LIABILITY IF UNABLE TO PERFORM

In case Landlord is prevented from making any repairs, decorations or installing
any fixtures or articles of equipment, or performing any other covenant or duty,
whether expressed herein or implied, to be performed on Landlord's part, due to
the Landlord's inability to obtain, or difficulty in obtaining, labor or
materials necessary thereof, or due to any governmental rules or regulations
relating to the priority of national defense requirements or due to any other
cause beyond Landlord's control, Landlord shall not be liable to Tenant for
damages resulting therefrom; nor shall the same give rise to a claim in the
Tenant's favor that such failure constitutes actual or constructive, total or
partial eviction from the Premises.

16. INSURANCE

      (A) Tenant covenants and agrees, at its sole cost and expense, throughout
the duration of this Lease, to obtain, keep and maintain in full force and
effect for the mutual benefit of Landlord and Tenant, comprehensive liability
insurance claims for damage to persons or property arising out of the use and
occupancy of the Premises or any part or parts in limits not less than One
Million Dollars, ($l,000,000.00) for a combined single limit bodily injury,
property damage policy. Such public liability policy or policies shall name
Landlord as an additional insured. Tenant will supply Landlord with certificates
of insurance evidencing the term of this Lease prior to taking occupancy.

      (B) All insurance provided for in this paragraph 16 may be in the form of
a general coverage, floater policy or so called blanket policies which may be
furnished by Tenant, or the parent corporation of Tenant or any related entity.

      (C) Landlord shall keep the building containing the Premises insured
against loss or damage by fire with extended coverage endorsement in an amount
not less than 80% of the full insurable value thereof. Tenant agrees to pay its
proportionate share of the cost of said insurance during the term hereof. Said
proportionate share shall be determined by multiplying the cost of said
insurance by a fraction, the numerator of which shall be the square foot area of
the Premises and the denominator the total rentable square foot area of the
building of which the Premises are


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a part. A statement of the cost of said insurance shall be rendered to Tenant
and shall be payable on or before the end of the month in which said statement
is rendered.

17. INDEMNITY

Except as otherwise provided in Section 13 hereof, Tenant shall indemnify
Landlord against any reasonable expense, loss or liability paid, suffered or
incurred as the result of any material breach by Tenant, Tenant's agents,
servants, employees, contractors, invitees or licensees, of any covenant or
condition of this Lease, or the carelessness, negligence or improper conduct of
Tenant, Tenant's agents, servants, employees, contractors or invitees. Tenant's
liability under this Lease extends to the acts and omissions of any sub-tenant,
and any agent, servant, employee, invitee or licensee of any such sub-tenant.

18. WAIVER OF SUBROGATION

Tenant hereby releases Landlord from any and all liability for any loss or
damage caused by fire, or other casualty to the property of Tenant on the
Premises or the contents of the Premises even if such fire or other causality
shall be brought about by the fault or negligence of Landlord or its agents, to
the extent that such liabilities and/or damages are actually reimbursed by
Landlord's insurance.

19. MECHANIC'S LIEN

Tenant shall not do or suffer anything to be done whereby the Premises may be
encumbered by any mechanic's lien and shall, whenever and as often as any
mechanic's lien is filed against the Premises for labor or material furnished or
to be furnished to Tenant, discharge the same of record within ten (10) days
after the date of filing. Notice is hereby given that Landlord shall not be
liable for any labor or materials furnished or to be furnished to Tenant upon
credit, and that no mechanic's or other lien for any such labor or materials
shall attach to or affect the reversionary or other estate or interest of
Landlord in and to the Premises herein demised.

20. DEFAULT CLAUSE

Each of the following shall be deemed a default by Tenant and a breach of this
Lease:

      (A) Tenant's failure to make payment for the rent herein reserved or any
part thereof, for a period of ten (10) days after written notice delivered to
the Tenant.

      (B) Failure by Tenant to perform any other material covenant or condition
of this Lease on the part of Tenant to be performed for a period of thirty (30)
days after service of notice thereof by Landlord on Tenant, provided however,
that if the nature of Tenant's default is such that it cannot be cured solely by
payment of money and that more than thirty (30) days may be


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reasonably required for such cure, then Tenant shall not be deemed to be in
default if Tenant shall commence such cure within such thirty (30) day period
and shall thereafter diligently prosecute such cure to completion.

21. REMEDIES IN EVENT OF DEFAULT; NOTICE OF TERMINATION

In the event of any such default of Tenant, and at any time thereafter, Landlord
may serve a written notice upon Tenant that Landlord elects to terminate this
Lease upon a specified date not less than thirty (30) days after the date of the
serving of such notice, and this Lease shall then expire on the date so
specified as if that date had been originally fixed as the expiration date of
the term herein granted. No defaults shall be deemed waived unless in writing
and signed by Landlord.

22. RE-ENTRY

In the event this Lease shall be terminated as hereinbefore provided, or by
summary proceedings or otherwise, or in the event that the Premises shall be
abandoned by Tenant, during the Lease Term, Landlord, or its agents, servants or
employees, may, immediately or any time thereafter, re-enter and resume
possession of said Premises or such part thereof, and remove all persons and
property therefrom, either by summary dispossess proceedings or by a suitable
action or proceedings at law.

23. RELETTING

In the event this Lease shall be terminated as provided in Article 21 hereof, by
summary proceedings or otherwise, or if the Premises shall be abandoned by
Tenant, or shall become vacant during the Term hereof, Landlord may, in its own
name, but as agent for Tenant if the Lease be not terminated, or if the Lease is
terminated, in its own behalf, relet the whole or any portion of said Premises,
for any period equal to or greater or less than the remainder of the original
Lease Term, for any sum which it may deem reasonable, to any tenant which it may
deem suitable and satisfactory, and for any use and purpose which it may deem
appropriate. In no event, however, shall Landlord be under any obligation to
relet the Premises for any purpose, other than that specified in this Lease
which the Landlord may regard as injurious to the Premises or to any tenant
which Landlord, in the exercise of reasonable discretion, shall deem to be
objectionable.

24. MEASURE OF DAMAGES IN EVENT OF DEFAULT

In the event that this Lease be terminated by summary proceeding, or otherwise,
or if the Premises are abandoned, and whether or not the Premises be relet,
Landlord shall be entitled to recover from Tenant and Tenant shall pay to
Landlord, the following:


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      (A) An amount equal to all reasonable expenses, if any, including
reasonable counsel fees incurred by the Landlord in recovering possession of the
Premises, and all reasonable costs and charges for the care of said Premises
while vacant, not otherwise the obligation of Landlord, which damages shall be
due and payable by Tenant to Landlord at such time or times as such expenses are
actually incurred by Landlord; and

      (B) An amount equal to the amount of all rent and additional rent reserved
under this Lease, less the net rent, if any, collected by Landlord on reletting
the Premises, which shall be immediately due and payable by Tenant to Landlord
and Landlord shall be entitled thereupon to recover same from Tenant on the
several days on which the rent and additional rent reserved in this Lease would
have become due and payable; that is to say, upon each of such days Tenant shall
pay to Landlord the amount of deficiency then existing. Such net rent collected
on reletting by Landlord shall be computed by deducting from the gross rents
collected all reasonable expenses incurred by the Landlord in connection with
the reletting, but shall not include the cost of performing any covenant
contained in paragraph 24.

Without any previous notice or demand, separate actions may be maintained by
Landlord against Tenant from time to time to recover any damages, which, at the
commencement of any such action, have then or theretofore become due and payable
to Landlord under paragraph 24, without waiting until the end of the original
Lease Term.

25. COVENANTS INDEPENDENT

Each and every covenant contained in this Lease shall be deemed separate and
independent, and not dependent on other provisions of this Lease or the use and
occupation of the Premises by Tenant, and the performance of any such covenant
shall not be considered to be rent or other payment for the use of said
Premises.

26. LANDLORD MAY CURE DEFAULTS

In the event of any material breach hereunder by Tenant, Landlord shall have the
right to cure such breach for the account and at the expense of Tenant. However,
Landlord shall give Tenant prior written notice of its intention to exercise its
said right hereunder and a reasonable opportunity for Tenant to cure any such
breach. If Landlord at any time, by reason of such breach, is compelled to pay,
any sum of money or do any act which will require the payment of any sum of
money, or is compelled to incur any expense, including reasonable attorney's
fees, in instituting, prosecuting and/or defending any action or proceeding to
enforce Landlord's rights hereunder, the sum or sums so paid by Landlord, with
all interest, and costs, shall be deemed to be additional rent hereunder and
shall be due from Tenant to Landlord on the first day of the month following the
incurring of such respective expenses.


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27. REAL ESTATE TAXES AND ASSESSMENTS

      (A) Tenant shall in all instances, pay as additional rent a portion of all
real estate taxes including extraordinary and/or special assessments (and all
costs and fees incurred by Landlord in contesting the fees) which may be levied
or assessed by apparent lawful taxing authority against the land, building and
all other improvements of which the Premises are a part. Such portion shall be
determined as follows: the Tenant shall pay that portion of such taxes as shall
be equal to the product obtained by multiplying said taxes by a fraction, the
numerator of which shall be the square foot area of the Premises and the
denominator the total rentable square feet of the building of which the Premises
are a part. Statement of such additional rent, including all taxes levied or
assessed in each calendar year, shall be rendered to Tenant and shall be paid on
or before the end of the month in which the statement is rendered, but in no
event shall such payment be due fewer then ten (10) days from the date such
statement is received. A tax bill submitted to Tenant shall be conclusive
evidence of the amount of taxes assessed or levied. Such additional rent
attributable to the year in which the term of this lease terminates shall be
apportioned from the date of the commencement of the term of this lease to the
end of the calendar year in which the lease commences or from the beginning of
the calendar year in which this lease terminates to the date of the termination
of the term of this Lease as the case may be and shall be paid within ten (10)
days after demand therefore. Each tax or assessment levied during the calendar
years in which this lease commences and terminates shall be included in the
computation of Tenant's portion regardless of the date of the commencement or
termination of the term of this lease.

      (B) Tenant shall pay before delinquency any and all taxes, assessments,
license fees and public charges levied, assessed or imposed and which become
payable during the lease term upon leasehold improvements, fixtures, furniture,
appliances and personal property installed or located in or on the Premises. If
any such taxes, assessments, license fees, or public charges are not levied,
assessed or imposed separately upon such property, a fair and equitable
allocation of such taxes, assessments, license fees or public charges shall be
made between such property included in the same tax assessment or other bill.

28. LATE CHARGES

A charge equivalent to five percent (5%) of the payment amount will be due for
any rent received after the 7th day of the month. Notwithstanding the above
charges, this Lease shall be considered in default if payment is not received
within ten (10) days of receipt of notice from Landlord that such payment is
due.


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29. COMMON AREAS

      (A) Common areas and facilities furnished by Landlord shall include
parking area, access driveways, and such other areas, facilities, and exterior
utilities as may be furnished by Landlord and designated for the benefit of the
Tenants, all of which areas and facilities shall be subject to exclusive control
and management by Landlord. Landlord shall have the right from time to time to
establish, modify and enforce all reasonable rules and regulations in respect to
such areas, facilities and exterior utilities and use thereof

      (B) Tenant shall pay to Landlord as additional rent a portion (as
determined pursuant to Paragraph (C) hereof) of each year's cost of the snow
plowing for the parking areas and sidewalks, landscaping, lawn maintenance,
driveway maintenance and exterior utilities.

      (C) At the termination of each maintenance year for snow plowing,
landscaping, lawn maintenance, driveway maintenance and exterior utilities, the
Landlord shall submit to Tenant a statement of the operating cost for such
services. Tenant shall pay as Tenant's portion of annual operation cost of the
common area an amount equal to the product obtained by multiplying the estimate
by a fraction, the numerator of which is the square foot area of the Premises
demised by this Lease and the denominator of which is the square foot area of
the total leasable area of the building of which the Premises are a part.

30. HOLDING OVER

Any holding over after the expiration of the term hereof, with the consent of
the Landlord, shall be construed to be a tenancy from month to month at the
rents herein specified (pro-rated on a monthly basis) and shall otherwise be on
the terms and conditions herein specified so far as applicable.

31. BANKRUPTCY

In order to more effectively secure to the Landlord the rent and other terms
herein provided, it is agreed as a further condition of this Lease that the
filing of any petition in bankruptcy, or assignment for the benefit of creditors
by or against the Tenant or any guarantor of Tenant's obligations hereunder
shall be deemed to constitute a breach of this Lease, and thereupon ipso
facto and without entry or any other action by the Landlord this Lease shall
become and be terminated and notwithstanding any other provision of this Lease
the damages for such breach in an amount equal to the amount of the rent
reserved in this Lease for the residue to the term hereof, less the fair rental
value of the Premises for the residue of said term plus all costs of rerenting.


                                       13
<PAGE>   14

32. SIGNS

Tenant shall not place, erect or install any signs on the outside or the inside
or upon the roof of the building or allow printed displays or show window
lettering in such manner as to be seen from the exterior of building without
prior written approval by Landlord. Any such sign permitted shall comply with
sign regulations which shall be established by Landlord. All such signs shall be
maintained in good and safe condition and appearance by the Tenant at its own
expense. Tenant shall repair damage to the Premises, either inside or outside,
resulting from the erection, maintenance or removal of said signs. Landlord
shall allow Tenant to place a building mounted sign similar to the sign for
Erdman Anthony Engineers on the building located at 2165 Brighton Henrietta
Townline Road. Landlord to approve sign plans prior to installation.

33. VENDING MACHINES

Tenant may, if Tenant so elects, install on the Premises and operate vending
machines to dispense hot and cold beverages, ice cream, candy and cigarettes.
Such machines shall be maintained in a neat and sanitary condition and shall
comply with all applicable laws and ordinances. Any contract entered into by
Tenant with third parties or the installation and/or maintenance of such vending
machines shall provide that Landlord shall have no liability in connection
therewith.

34. RULES

In the event that Landlord receives written notification that the Premises do
not conform to applicable requirements of law, requirements of duly constituted
authority, or any Board of Underwriters, Landlord shall cause the Premises to be
brought into compliance with said laws or regulations. In the event that Tenant
receives written notice that it is not in full compliance with all applicable
statutes, ordinances, rules and regulations pertaining to Tenant's use of the
Premises, or to any Tenant's alterations or additions to the Premises, then
Tenant shall fully comply with all such applicable statutes or rules.

35. REMEDIES CUMULATIVE

The rights given to Landlord herein are in addition to any rights that may be
given to Landlord by any statute or otherwise.

36. WAIVER OF RIGHT OF REDEMPTION

Tenant, for itself and for all persons claiming through or under it, hereby
expressly waives any and all rights which are or may be conferred upon Tenant by
a present or future law to redeem


                                       14
<PAGE>   15

said Premises, or to any new trial in any action of ejectment under any
provision of law, after reentry thereupon by Landlord. If Landlord shall acquire
possession of said Premises by summary proceedings, or in any other lawful
manner without judicial proceedings, it shall be deemed a reentry within the
meaning of that word as used in this Lease.

37. SECURITY DEPOSIT

Tenant has deposited with Landlord the sum of $9,116.67 as security for the
faithful performance and observance by Tenant of the terms, provisions and
conditions of this Lease; it is agreed that in the event Tenant defaults in
respect of any of the terms, provisions and conditions of this Lease, including,
but not limited to, the payment of rent and additional rent, Landlord may at its
option use, apply or retain the whole or any part of the security so deposited
to the extent required for the payment of any rent and additional rent or any
sum as to which Tenant is in default or for any sum which Landlord may expend or
may be required to expend by reason of Tenant's default in respect of any of the
terms, covenants and conditions of this Lease, including but not limited to, any
damages or deficiency in the reletting of the Premises whether such damages or
deficiency accrued before or after summary proceedings or other re-entry by
Landlord. In the event that Tenant shall fully and faithfully comply with all of
the terms, provisions, covenants and conditions of this Lease, the security
shall be returned, with interest as required under New York Law, to Tenant after
the date fixed as the end of the Lease and within a reasonable time after
delivery of entire possession of the demised Premises to Landlord. In the event
of a sale of the land and building or leasing of the buildings, of which the
demised Premises form a part, Landlord shall have the right to transfer the
security to the vendee or lessee, and Landlord shall thereupon be released by
Tenant from all liability for the return of such security; and Tenant agrees to
look to the new Landlord solely for the return of said security; and it is
agreed that the provisions hereof shall apply to every transfer or assignment
made of the security to a new Landlord. Tenant further covenants that it will
not assign or encumber or attempt to assign or encumber the monies deposited
herein as security and that neither Landlord nor its successors or assigns shall
be bound by any such assignment, encumbrance, attempted assignment or attempted
encumbrance.

38. SUBORDINATION TO MORTGAGES

This lease is and shall be subject and subordinate to any mortgage or mortgages
and to any extensions or modifications thereof now in force or which shall at
any time be placed upon the Premises or any part thereof or the building of
which the Premises is a part of. The Tenant agrees that it will, upon demand,
execute and deliver such instruments as necessary to effect more fully such
subordination of this lease to the lien of any such mortgage or mortgages as
shall be desired by any mortgagee or proposed mortgagee and in the event of the
failure of the lessee


                                       15
<PAGE>   16

to execute such instrument, the Lessee hereby nominates and appoints the Lessor
attorney-in-fact for the purpose of executing any such instrument of
subordination.

39. COVENANT OF QUIET ENJOYMENT

If and so long as Tenant pays the rent and additional rent reserved by this
Lease, and performs and observes all the covenants and provisions hereof, Tenant
shall quietly enjoy the Premises, subject, however, to the terms of this Lease.

40. ENTIRE AGREEMENT

This instrument contains all the agreements and conditions made between the
parties hereto and supersedes all prior or other leases, agreements and
representations in connection with the Premises and may not be modified orally
or in any other manner than by an agreement in writing, signed by all the
parties hereto or their respective successors in interest. The receipt of rent
by Landlord, with knowledge of any breach of this Lease by Tenant or of any
default on the part of Tenant in this observance or performance of any of the
conditions or covenants of this Lease shall not be deemed to be a waiver of any
provision of this Lease. If the Tenant makes any payment of any amount less than
that due hereunder, Landlord, without notice, may accept the same as a payment
on account; Landlord shall not be bound by any notation on any check involving
such payment or any statement in any accompanying letter. No failure on the part
of Landlord to enforce any covenant herein contained nor any waiver of any right
thereunder by Landlord, unless in writing, shall discharge or invalidate such
covenant or provision or affect that right of Landlord to enforce the same in
the event of any subsequent breach or default. The receipt by Landlord of rent
or any other sum of money or any other consideration hereunder paid by Tenant
after the termination, in any matter of the term herein demised shall not
reinstate, continue, or extend the term herein demised, or destroy, or in any
manner impair the efficiency of any such notice of termination as may have been
give hereunder by Landlord or Tenant prior to the receipt of any such sum of
money or other consideration, unless so agreed to in writing and signed by
Landlord. Neither acceptance of the keys nor any other act or thing done by
Landlord or any agent or employee during the term herein demised shall be deemed
to be an acceptance of a surrender of said Premises, excepting only an agreement
in writing signed by Landlord accepting or agreeing to accept such a surrender.

41. EFFECT OF CONVEYANCE

The term "Landlord" as used in this Lease, means only the present Owner of the
Premises so that, in the event of any sale of the Premises or in the event of a
lease by Landlord of the Premises subject to this Lease or assignment by
Landlord of this Lease, Landlord shall be and hereby is entirely freed and
relieved of all covenants and obligations of the Landlord hereunder


                                       16
<PAGE>   17

arising subsequent to any such transfer and provided any such transferee assumes
in writing the obligations of Landlord hereunder and a copy of such assumption
is delivered to Tenant, and it shall be deemed and construed without further
agreement between the parties or between the parties and the purchaser at any
such sale or the new lessee of the Premises or assignee of this Lease that such
purchaser or said new lessee, or said assignee has assumed and agreed to carry
out any and all covenants and obligations of Landlord hereunder. If any landlord
named herein be acting in a fiduciary or representative capacity, the
termination, in whole or in part, of such capacity shall be deemed a transfer
within the meaning of this paragraph.

42. TOWN REGULATIONS AND OBLIGATIONS

Tenant shall have full responsibility of complying with all Town regulations
including but not limited to, use as described by zoning ordinances.

43. CONSTRUCTION OF LEASE

Words of any gender used in the Lease shall be held to include any other gender,
and words in the singular number shall be held to include the plural, when the
sense requires. Consents required of Landlord hereunder shall not be
unreasonably withheld or delayed.

44. RIGHTS OF SUCCESSORS AND ASSIGNS

The covenants and agreements contained in the within Lease shall apply to, inure
to the benefit of, and be binding upon the parties hereto and upon their
respective successors in interest and legal representatives, except as expressly
otherwise hereinabove provided.

45. LEASE RENEWAL

Lease may be extended for an additional term of five (5) years upon the same
terms, covenants and conditions herein except this clause relating to renewal
and to rental (the "renewal term"). Lease rent shall be adjusted from year I
using CPI Index or a 15% increase, whichever is less. This adjustment shall be
for years 8 through 12. Notification of the Lease extension shall be 180 days
prior to Lease termination date, by written notice from Tenant to Landlord and
provided Tenant at the time of such notice shall not be in default in the terms
hereof.

46. ENVIRONMENTAL LAWS

      (A). Tenant covenants and agrees as follows:

      (1). Tenant shall keep the Premises free of all Hazardous Substances and
shall not knowingly cause or permit the Premises or any part thereof to be used
for the treatment, generation, transportation,


                                       17
<PAGE>   18

processing, production, disposal, storage or handling of any hazardous
substances, and shall promptly remove from the Premises and shall dispose of all
Hazardous Substances by-products, arising from Tenant's use of the Premises, in
compliance with all applicable Environmental Laws.

      (2). Tenant shall comply with all applicable Environmental Laws and shall
obtain and comply with all Environmental Permits relating to Tenant's use of the
demised premises.

      (3). Tenant shall not cause or permit any change to be made in the present
or intended use of the demised premises which would (1) involve the storage,
treatment, generation, transportation, processing, handling, production or
disposal of any Hazardous Substance or the use of the demised premises as a
landfill or other waste disposal site or for military, manufacturing or
industrial purposes or for the storage of petroleum or petroleum based products,
(2) violate any applicable Environmental Law, (3) constitute non-compliance with
any Environmental Permit.

      (4). Each party hereto agrees to provide the other with a copy of all
notifications which it gives or receives with respect to any past or present
release or the threat of a release of any Hazardous Substance on, at or from the
demised premises given by or on behalf of Tenant to any federal, state or local
governmental agencies or authorities or received by or on behalf of Tenant from
any source whatsoever.

      (5). Tenant shall at all times allow Landlord and its officers, employees,
agents, representatives, contractors and subcontractors reasonable access to the
demised premises for the purpose of ascertaining site conditions, including, but
not limited to, subsurface conditions.

      (6). If at any time Tenant obtains any evidence or information which
suggests that potential environmental problems may exist at the demised premises
arising directly from Tenant's use of the demised premises, Landlord may require
that a full or supplemental environmental inspection and audit report with
respect to the demised premises of a scope and level of detail satisfactory to
Landlord be prepared by an environmental engineer or other qualified person
acceptable to Landlord, at Tenant's sole cost and expense. If said audit report
indicates the presence of any Hazardous Substance or a release or the threat of
a release on, at or from the demised premises arising from Tenant's use of the
demised premises, Tenant shall promptly undertake and diligently pursue to
completion all necessary, appropriate and legally authorized investigative,
containment, removal, clean up and other remedial action, using methods
recommended by the environmental engineer or other person who prepared said
audit report and acceptable to the appropriate federal, state and local
regulatory authorities.

      (B). (1). Tenant covenants and agrees, at its sole cost and expense, to
indemnify, protect, defend and save harmless Landlord from and against any and
all damages, losses, liabilities, obligations, penalties, claims, litigation,
demands, defenses, judgments, suits, actions,


                                       18
<PAGE>   19

proceedings, costs, disbursements and/or expenses (including, without
limitation, attorneys' and experts' fees, expenses and disbursements) of any
kind or nature whatsoever which may at any time be imposed upon, incurred by or
asserted or awarded against Landlord and Tenant relating to, resulting from or
arising out of(i) Tenant's use of the demised premises for the storage,
treatment, generation, transportation, processing, handling, production or
disposal of any Hazardous Substance or as a landfill or other waste disposal
site or for military, manufacturing or industrial purposes or for the storage of
petroleum or petroleum based products, (ii) the presence of any Hazardous
Substance or a Release or the threat of a release on, at or from the demised
premises arising directly from Tenant's use of the demised premises, (iii) the
failure to promptly undertake and diligently pursue to completion all necessary,
appropriate and legally authorized investigative, containment, removal, clean up
and other remedial actions with respect to a Release or the threat of a Release
on, at or from the demised premises arising from Tenant's use of the demised
premises, (iv) human exposure to any Hazardous Substance, noises, vibrations or
nuisances of whatever kind to the extent the same arise from the use and
operation of the demised premises, (v) a violation by Tenant of any applicable
Environmental Law, (vi) noncompliance by Tenant with any Environmental Permit or
(vii) a material misrepresentation or inaccuracy in any representation or
warranty or a material breach of or failure to perform any covenant made by
Tenant in this Paragraph 46.

          (2). Landlord covenants and agrees, at its sole cost and expense, to
indemnify and hold Tenant harmless from and against any and all damages, losses,
liabilities, obligations, penalties, claims, litigation, demands, defenses,
judgment, suits, actions, proceedings, costs, disbursements and/or expenses
(including, without limitation, attorneys' and experts' fees, expenses and
disbursements) of any kind or nature whatsoever which may at any time be imposed
upon, incurred by or asserted or award against Landlord and Tenant arising out
of (I) the presence or release of any Hazardous Substance on or about the
Premises as of the date hereof; or (ii) the presence of any Hazardous Substance
on or about the Premises as result of any act or omission by Landlord or any
third party.

      (C). All capitalized terms used in this Section and not heretofore defined
shall have the meanings set forth below.

      "Environmental Laws" means all federal, state and laws, statutes,
ordinances and codes governing the use, storage, treatment, generation,
transportation, processing, handling, production or disposal of hazardous
substances and the rules, regulations, policies, guidelines, interpretations,
decisions, orders and directives of federal, state and local governmental
agencies and authorities promulgated with respect thereto.

      "Environmental Permits" means all permit, licenses, approvals,
authorizations, consents or registrations required by any applicable
Environmental Law in connection with the ownership, use and/or operation of the
demised premises for the storage, treatment, generation,


                                       19
<PAGE>   20

transportation, processing, handling, production or disposal of hazardous
substances or the sale, transfer or conveyance of the demised premises.

      "Hazardous Substance" means, without limitation, any flammable explosive,
radon, radioactive materials, asbestos, urea formaldehyde foam insulation,
polychlorinated biphenyl's, petroleum and petroleum products, methane, hazardous
materials, hazardous wastes, hazardous or toxic substances or related materials,
as defined in the Comprehensive Environmental Response, Compensation and
Liability Act of 1980, as amended (42 U.S.C. Section 9601, et seq.), the
Hazardous Materials Transportation Act, as amended (49 U.S.C. Section 1801, et
seq.), the Resource Conservation and Recovery Act, as amended (42 U.S.C. Section
6901, et seq.), the Toxic Substances Control Act, as amended (15 U.S.C. Section
2601, et seq.), Articles 15 and 27 of the New York State Environmental
Conservation Law or any other applicable Environmental Law and the regulations
promulgated thereunder.

      "Release" has the same meaning as given to that term in the Comprehensive
Environmental Response, Compensation and Liability Act of 1980, as amended (42
U.S.C. Section 9601, et seq.), and the regulations promulgated thereunder.

47. RIGHT OF FIRST OFFER

Tenant shall have a right of first offer to lease the adjacent space to the
south of their existing space, should this space become available during the
term of the lease

      (a). Exercise of Right to Lease REQ Premises. Landlord shall give Tenant
written notice ("Landlord's Notice") at the time that Landlord intends to offer
the REQ Premises for lease. Landlord's Notice shall set forth the rent
applicable to such RFO Premises, the improvements to the REQ Premises which
Landlord intends to make, the commencement date for the RFO Premises and the
expiration date for the REQ Premises. Tenant shall have the right, exercisable
upon written notice given to Landlord within ten (10) days after the giving of
Landlord's Notice, to lease the REQ Premises. If Tenant fails to give such
notice in the time period set forth herein, Tenant shall have no further right
to lease the REQ premises pursuant to this Section 47.

      (b) Lease Provisions Applying to REQ Premises. The leasing to Tenant of
the REQ Premises shall be upon all of the terms and conditions of this Lease
unless stated otherwise in Landlord's Notice and except that the REQ Premises
shall be delivered by Landlord and accepted by Tenant in accordance with the
terms set forth in Landlord's Notice.

      (c) Execution of Lease Amendments. Notwithstanding the fact that Tenant's
exercise of the above-described right of first offer to lease REQ Premises shall
be self-executing, the parties hereby agree promptly to execute a lease
amendment reflecting the addition of the REQ Premises, the adjustments in rent
as well as any modifications of the provisions of the Lease as


                                       20
<PAGE>   21

shall be necessary to properly include the RFO Premises within the terms and
conditions of this Lease.

48. NOTICES

All notices shall be sent by registered mail, return receipt requested, to the
following address:

                                    LANDLORD
                             Mr. Richard R. LeFrois
                            1020 Lehigh Station Road
                                  P.O. Box 230
                           Henrietta, New York 14467

                                     TENANT
                             Fibernet Telecom, Inc.
                              121 Erie Canal Drive
                           Rochester, New York 14626

Any notice shall be considered to have been given, in the case of letter, at
5:00 p.m. local time on the date set forth on the post mark appearing on the
envelope.

49. PAYMENTS

All payments shall be sent by to the following address:

MR. RICHARD R. LEFROIS, P.O. Box 92878, Department No. 102, Rochester, New
York 14692


                                       21
<PAGE>   22

IN WITNESS WHEREOF, Landlord and Tenant have duly executed this Lease as of the
day and year first above written.

                                 RICHARD R. LEFROIS


LANDLORD                         By: /s/ Richard R. LeFrois
                                     ---------------------------------
                                     Mr. Richard R. LeFrois, Landlord
                                 
                                     3-19-98
                                     ---------------------------------
                                     Date


WITNESS                          By: /s/ [ILLEGIBLE]
                                     ---------------------------------

                                     3-18-98
                                     ---------------------------------
                                     Date

                                 FIBERNET TELECOM, INC.
                                 

TENANT                           By: /s/ [ILLEGIBLE]
                                     ---------------------------------

                                     3-17-98
                                     ---------------------------------
                                     Date
                                 

WITNESS                          By: /s/ [ILLEGIBLE]
                                     ---------------------------------

                                     3-17-98
                                     ---------------------------------
                                     Date


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