TENTH AMENDMENT TO LEASE




         THIS TENTH  AMENDMENT  TO LEASE (the  "Amendment")  is made and entered
into this ______ day of December,  1997, by and between LAFP-SF, Inc., successor
in interest to The Prudential Insurance Company Of America ("Landlord"),  having
an office c/o Lowe Enterprises Colorado,  Inc., 1475 Lawrence Street, Suite 210,
Denver,  Colorado 80202, and Data Transmission  Network Corporation  ("Tenant"),
having an office at 9110 West Dodge Road, Suite 200, Omaha, Nebraska 68114.


                                    RECITALS

A.       The  Prudential  Insurance  Company  of America  and Data  Transmission
         Network  Corporation entered into that certain Lease dated as of May 2,
         1995, for Suites #175A, #110, #200, #300, #301, #310, #320, #325, #340,
         #360,  #362, and #100  containing  75,931 rentable square feet (RSF) in
         the Building known as Embassy  Plaza,  located at 9110 West Dodge Road,
         Omaha, Nebraska ("the Premises").

B.       Subsequently,  The  Prudential  Insurance  Company Of America  and Data
         Transmission  Network  Corporation  executed a First Amendment To Lease
         dated September 29, 1995, a Second  Amendment To Lease dated January 5,
         1996, a Third  Amendment To Lease dated  January 5, 1996,  and a Fourth
         Amendment To Lease between LAFP-SF,  Inc. and Tenant dated December 23,
         1996, a Fifth  Amendment To Lease dated July 7, 1997, a Sixth Amendment
         To Lease  dated  July 7,  1997,  a  Seventh  Amendment  To Lease  dated
         September  19, 1997, an Eighth  Amendment To Lease dated  September 19,
         1997,  and a Ninth  Amendment To Lease dated  September  19, 1997.  The
         combined terms of the Lease and subsequent  Amendments  shall herein be
         referred to as the "Lease".
         Under the Lease the Premises consists of a total of 107,576 RSF.

C.       All capitalized terms not defined herein shall have the meanings
         ascribed to them in the Lease.



         NOW,  THEREFORE,  in consideration of the foregoing  promises and other
good and  valuable  considerations,  the  receipt and  sufficiency  of which are
hereby acknowledged, the parties hereto covenant and agree as follows:

1.       Parking.  Landlord and Tenant  recognize that the  construction  of the
         additional  parking  spaces  required  under  paragraph  1 of the Fifth
         Amendment To Lease, as referenced above, is substantially  underway and
         has been delayed from time to time due to weather conditions beyond the
         control of the Landlord.  In  consideration  of  Landlord's  reasonable
         efforts to complete  said parking as weather  permits  (estimated to be
         prior to May 1, 1998) and other  provisions of this  Amendment,  Tenant
         agrees,  effective  December  1,  1997,  to  commence  payment  of  the
         additional  Base Rent called for in paragraph 2 of said Fifth Amendment
         To Lease.


2.       Tenant  Improvements.  As a part  of  this  Amendment,  paragraph  1 of
         Article  II,  of  Exhibit  B to  the  Fourth  Amendment  To  Lease,  as
         referenced  above,  shall be modified to provide Tenant an extension of
         the time frame for  submittal  of invoices  relative to Tenant's use of
         the tenant finish  allowance  provided  under this Fourth  Amendment To
         Lease.  Such  extension  shall be for a period of up to four (4) months
         through April 30, 1998.


3.       Effect of  Agreement.  Except as  herein  specifically  provided,  the
         terms and  conditions  of the Lease shall continue in full force and
         effect.


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4.       This  Amendment  shall be binding upon and inure to the benefit of the
         parties  hereto,  their  successors and assigns.



5.       The parties hereto hereby reaffirm and ratify all covenants, represen-
         tations  and warranties in the Lease as amended by this Amendment.



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


Tenant:                                     Landlord:

Data Transmission Network Corporation,          LAFP-SF, Inc.
a Delaware corporation

                                                By:  Lowe Enterprises Investment
                                                     Management, Inc.
By:                                             Its:  Authorized Agent
  -----------------------------------


Its:                                            By:
    ---------------------------------

                                                Its:
                                                    ----------------------------

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