SECOND AMENDMENT TO 1997 TERM CREDIT AGREEMENT


         THIS  SECOND  AMENDMENT  to 1997  TERM  CREDIT  AGREEMENT  (the  "First
Amendment")  is intended  to amend the terms of the 1997 Term  Credit  Agreement
(the "Agreement") dated as of February 26, 1997, among DATA TRANSMISSION NETWORK
CORPORATION; FIRST NATIONAL BANK OF OMAHA; FIRST NATIONAL BANK, WAHOO, NEBRASKA;
NBD BANK,  N.A.;  NORWEST  BANK  NEBRASKA,  N.A.;  THE SUMITOMO  BANK,  LIMITED;
MERCANTILE BANK OF ST. LOUIS, N.A.; U.S. BANK,  NATIONAL  ASSOCIATION  (formerly
First Bank, National Association);  BANK OF MONTREAL; and LASALLE NATIONAL BANK.
All terms and conditions of the Agreement  shall remain in full force and effect
except as expressly amended herein.  All capitalized terms herein shall have the
meanings prescribed in the Agreement. The Agreement shall be amended as follows:

         The parties hereby acknowledge that, effective as of the date hereof:

     1.  The following  definitions in Article I of the Agreement are amended as
         follows:

                   Banks:  FNB-O,  FNB-W, U.S. Bank,  Mercantile,  NBD, Norwest,
              Sumitomo,  Nationsbank,  LaSalle and Montreal, and such additional
              banks as may be added  hereto from time to time by mutual  written
              agreement of the parties.

         Operative

                   Documents:  This 1997 Loan Agreement, the Notes, the Security
              Agreement,  the financial  statements regarding the Collateral and
              the documents and certificates, other than the Purchase Agreement,
              delivered pursuant to Article VI.

     2.  Section 2.2 shall be amended to read as follows:

                   2.2 Notes.  The Notes shall bear  interest  on the  principal
              loan amount thereof outstanding through June 30, 1999, at the rate
              of 8.25% per annum;  thereafter  the interest rate for the balance
              of the term shall be set on June 30, 1999, at two percent  (2.00%)
              above  the  yield  on  constant   maturity   Treasury  Bonds  with
              maturities  of  three  years,  as  quoted  for  the  Business  Day
              immediately  preceding  June 30, 1999 in the  applicable  Release.
              Notwithstanding  the foregoing,  the Notes issued to the following
              Lenders  shall bear interest as follows:  (i) as to U.S.  Bank, at
              the rate of 8.36% per annum through June 30, 1999  (whereupon  the
              interest rate reset described above shall be applicable); and (ii)
              as to Mercantile, NBD, Sumitomo, Norwest, FNB-W and Montreal, at a
              variable rate per annum equal to New York Prime minus  one-half of
              one  percent  (0.5%).  After  an Event of  Default  has  occurred,
              interest  shall accrue:  (i) with respect to the fixed rate Notes,
              on the entire  outstanding  balance of principal and interest at a
              fluctuating  rate  equal to the  Revolving  Credit  Rate plus four
              percent  (4.00%);  and (ii) as to the floating rate Notes,  on the
              principal  loan amount  thereof at a rate per annum equal to three
              and one-half  percent (3.5%) above New York Prime.  Interest shall
              be  calculated  on actual days elapsed and a year of 360 days.  If
              the Borrower's most recent Quarterly Compliance  Certificate shows
              that, as of the end of the prior  quarter,  the Leverage Ratio was
              at such date more than thirty-six  (36), the current quarter shall
              be deemed a "Restricted Quarter." If, any time during a Restricted
              Quarter (including,  without limitation, during any period in such
              quarter   prior   to   delivery   of  the   Quarterly   Compliance
              Certificate),  the interest rate accruing on any Note is less than
              seven and one-half  percent  (7.50%),  a "Trigger  Event" shall be
              deemed to have  occurred.  Upon the occurrence of a Trigger Event,
              the Borrower  shall be obligated to pay the Lenders the  following
              fees: (i)  three-eighths of one percent (.375%) of the outstanding
              principal  balance  of such  Note  as of the  date  preceding  the
              Trigger  Event,  which  amount  shall  be  payable  promptly  upon
              invoicing  by FNB-O;  (ii) the same  amount as  computed in clause
              (i),  payable on the six-month  anniversary  of the Trigger Event;
              and (iii) the same amount as  computed  in clause (i),  payable on
              the twelve-month anniversary of the Trigger Event.

 
                                        1
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<PAGE>

     3.  Section 5.4 (a) shall be amended to read as follows:  

                   (a) The  Borrower  shall not at any time permit the  Leverage
              Ratio to exceed forty-eight (48).

     4.  Section 5.19 shall be amended to read as follows:

                   5.19 Capital  Expenditures.  The Borrower  shall not incur in
              any fiscal year, commencing with the fiscal year beginning January
              1, 1998,  capital  expenditures,  determined  in  accordance  with
              generally accepted accounting principles, of more than $2,000,000;
              provided,  however, that capital expenditures for (a) equipment to
              be used by subscribers of the Borrower, and (b) telecommunications
              equipment,  computer  equipment,  software and software consulting
              shall not be counted for purposes of this annual limitation.

     5.  Section 5.20 is hereby amended to read as follows:

                   5.20  Acquisitions.  The Borrower shall not acquire any stock
              or any equity interest in, or warrants therefor or securities into
              the same,  or a  substantial  portion of the  assets  of,  another
              entity without the prior written consent of the Lenders; provided,
              however,  that  the  Borrower  shall  be  permitted  to  make on a
              cumulative basis from and after July 1, 1998 such  acquisitions in
              an amount not to exceed Twenty Million  Dollars  ($20,000,000)  in
              the aggregate without the consent of the Lenders if:

                   (a) such acquisitions are in or from entities which:

                       (i) are in the business of  electronically  communicating
                           time-sensitive information to subscribers;

                       (ii)have their  principal place of business in the United
                           States or Canada; and

                       (iii) have a positive operating cash flow,  calculated in
                           the  same  method  as  is  used  to   calculate   the
                           Borrower's  Operating  Cash Flow for purposes of this
                           Agreement; and

                   (b) the Borrower or any  Subsidiary  is not, and  immediately
              after the making of such acquisition, will not be in default under
              any other  covenant or  provision  of this  Agreement  (including,
              without  limitation,  the covenants and  provisions  pertaining to
              minimum net worth and limitations on indebtedness); and

                   (c) no one  acquisition  shall  exceed  Ten  Million  Dollars
              ($10,000,000).
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<PAGE>

     6.  Exhibit  B is  hereby  amended  to read as shown on  Exhibit  B to this
         Second Amendment.

     7.  This Second  Amendment  shall not affect and there  remain  outstanding
         from the Borrower to the Banks, the existing Notes and the Related Bank
         Debt.

     8.  This Second Amendment may be executed in several  counterparts and such
         counterparts together shall constitute one and the same instrument.

     Except as expressly agreed herein,  all terms of the Agreement shall remain
in full force and effect.

     IN WITNESS WHEREOF,  the undersigned have executed this SECOND AMENDMENT TO
1997 TERM CREDIT AGREEMENT dated as of May 15, 1998.

                                       DATA TRANSMISSION NETWORK CORPORATION

                                       By /s/ Brian L. Larson
                                         Title:VP, CFO and Secretary





                                       FIRST NATIONAL BANK OF OMAHA



                                       By /s/ James P. Bonham
                                         Title:Vice President






NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:


                                      Borrower


                                       3
                                    - 518 -
<PAGE>





                                      THE SUMITOMO BANK, LIMITED


                                      By________________________________
                                        Title:


                                      By________________________________
                                        Title:







NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:


                                      Borrower


                                       4
                                    - 519 -
<PAGE>





                                      FIRST NATIONAL BANK, WAHOO,
                                      NEBRASKA



                                      By________________________________
                                        Title:








NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:


                                      Borrower


                                       5
                                    - 520 -
<PAGE>





                                      NBD BANK


                                      By________________________________
                                        Title:





NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:


                                      Borrower


                                       6
                                    - 521 -
<PAGE>




                                      NORWEST BANK NEBRASKA, N.A.




                                      By________________________________
                                        Title:





NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:


                                      Borrower


                                       7
                                    - 522 -
<PAGE>


                                      LASALLE NATIONAL BANK, a national
                                      banking association




                                      By________________________________
                                        Title:





NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:
                                      
                                      Borrower


                                       8
                                    - 523 -
<PAGE>






                                      MERCANTILE BANK OF ST. LOUIS, N.A.


                                      By________________________________
                                        Title:







NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:


                                      Borrower



                                       9
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<PAGE>





                                      U.S. BANK, NATIONAL ASSOCIATION


                                      By________________________________
                                        Title:





NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:


                                      Borrower



                                       10
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<PAGE>




                                      BANK OF MONTREAL,
                                      Chicago Branch




                                      By_______________________________
                                        Title:




NOTICE: A credit  agreement must be in writing to be enforceable  under Nebraska
law. To protect you and us from any  misunderstandings  or disappointments,  any
contract,  promise,  undertaking,  or offer to forebear repayment of money or to
make any other financial  accommodation in connection with this loan of money or
grant or extension of credit,  or any amendment of,  cancellation of, waiver of,
or  substitution  for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.

                                      INITIALED:


                                      Borrower




                                       11
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<PAGE>


                                    EXHIBIT B



                          TO 1997 TERM CREDIT AGREEMENT
                                      among
                           DATA TRANSMISSION NETWORK,
                          FIRST NATIONAL BANK OF OMAHA,
                      FIRST NATIONAL BANK, WAHOO, NEBRASKA,
                                    NBD BANK,
                          NORWEST BANK NEBRASKA, N.A.,
                           THE SUMITOMO BANK, LIMITED,
                       MERCANTILE BANK OF ST. LOUIS, N.A.,
                        U.S. BANK, NATIONAL ASSOCIATION,
                                BANK OF MONTREAL
                                       AND
                              LASALLE NATIONAL BANK



                              OFFICER'S CERTIFICATE



                                       12
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<PAGE>

                             COMPLIANCE CERTIFICATE
                      DATA TRANSMISSION NETWORK CORPORATION


First National Bank of Omaha                                Date

Attn:  James Bonham
16th & Dodge Streets
Omaha, Nebraska 68102

I certify that Data Transmission  Network  Corporation is in compliance with the
requirements set forth in the 1997 Term Credit Agreement (the "Agreement") dated
as of February 26, 1997,  between First  National Bank of Omaha,  First National
Bank, Wahoo, Nebraska,  NBD Bank, Norwest Bank Nebraska,  N.A., LaSalle National
Bank,The  Sumitomo Bank,  Ltd.,  Mercantile Bank of St. Louis,  N.A., U.S. Bank,
National Association, and Data Transmission Network Corporation.

The following  calculations  are as of  (statement  date) as required by Section
5.1(d) of said Agreement: 

Evaluations:

Total Indebtedness (TI):

Operating Cash Flow:      most recent month                 previous month
                          ending                            ending

    Net Income (loss)     ------------                      ------------
    Interest Expense      ------------                      ------------
    Depreciation          ------------                      ------------
    Amortization          ------------                      ------------
    Deferred Income   
     Taxes                ------------                      ------------
    Non-Ordinary
     Non-Cash
     Charges (Credits)    ------------                      ------------

    Total                 a)                                b)
                            ----------                        ----------

    Operating Cash Flow = OCF = (a+b)/2 =
                                          ------------
Leverage Ratio (TI/OCF):

Section 2.2
                                       13
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<PAGE>

     Trigger Fee:  If the  Leverage  Ratio is more than 36, then a one time
                   fee is due,  paid in three  installments  of 3/8% of the then
                   outstanding  principal  balances,  on any of the Notes  which
                   have an interest rate less than 7.5% per annum.  

                   Position:  A Trigger Event has/has not occurred.
Section 5.3

     Net Worth:    A  minimum  Net Worth  (exclusive  of  subordinated  debt) of
                   $23,500,000  plus fifty  percent (50%) of the net income (but
                   not losses) of the Borrower for each fiscal year,  commencing
                   with the fiscal  year  beginning  January 1, 1997;  provided,
                   however,  solely for purposes of determining  compliance with
                   the  provisions  of this Section  5.3,  "Net Worth" shall not
                   include any subordinated debt.


                   Minimum  Net  Worth  (exclusive  of  subordinated   debt)=  $
                   23,500,000.

                   Net Income              Year ending            Addition (50%)

                   $____________             12/31/97             $___________
Total Minimum Net
   Worth                                                          $

Position:

Total Net Worth (exclusive of subordinated debt) = $_____________

The Borrower [is/is not] in compliance with Section 5.3.

Section 5.4

             Indebtedness:    At no time will the Leverage Ratio  exceed 48

                              Position:            Leverage Ratio =      
                                                                   ---------


    Total
    Indebtedness
    plus
    subordinated
    debt plus
    guaranty
    contingencies
    (Adjusted
    Total
    Indebtedness or
    ATI)1:                    At no time will Adjusted Total Indebtedness
                              exceed 60 x OCF

    Position:                 Adjusted Total Indebtedness = $
                              (60 x OCF) - (ATI) = $

The Borrower [is/is not] in compliance with Section 5.4.

                                       14
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<PAGE>

Section 5.7

    Distributions: Neither the Borrower  nor any  Subsidiary  shall  declare any
                   dividends  (other  than  dividends  payable  in  stock of the
                   Borrower or dividends or distributions  from any consolidated
                   Subsidiary) or make any cash  distribution  in respect of any
                   shares of its capital stock or warrants of its capital stock,
                   without the prior  written  consent of the Lenders;  provided
                   that the Borrower  need not obtain the Lenders'  consent with
                   respect  to  dividends  in any one (1) year  which are in the
                   aggregate  less  than  25% of the  Borrower's  Net  Operating
                   Profit  After Taxes in the  previous  four (4)  quarters,  as
                   reported to the Lenders pursuant to Section 5.1.


                       Position:                Net Operating Profit
                              After Taxes for
                              last four (4) quarters          =  ______________

                                                                         x  .25

                              Available for dividends
                              or distributions in the most
                              recent quarter plus the
                              prior three (3) quarters        =  ______________

                              Dividends and distributions
                              (excluding dividends payable
                              solely in stock of the Borrower
                              and distributions from consolidated
                              Subsidiaries) declared or paid 
                              in the most recent quarter plus
                              the prior three (3) quarters    = _______________

The Borrower [is/is not] in compliance with Section 5.7.

                                       15
                                    - 530 -


<PAGE>

Section 5.15

    Interest                  The ratio of OCF to Interest Expense ("IE")
     Coverage:                at the end of each  quarter  will not be less than
                              2.25 to 1.0 (225%).

    Position:                 OCF = $
                              IE = $
                              OCF/IE =        %

The Borrower [is/is not] in compliance with section 5.1.5.

Section 5.19

Capital Expenditures: 
                   The Borrower shall not make capital  expenditures (other than
                   permitted  earning  assets  specified in Section 5.19) in any
                   fiscal  year,  commencing  with  the  fiscal  year  beginning
                   January 1, 1998, in excess of $2,000,000.

                   Position:  Capital Expenditures (other than permitted earning
                              assets specified in Section 5.19) this fiscal year
                              = $_____________

The Borrower [is/is not] in compliance with Section 5.19.


Section 5.20

     Acquisitions: The  Borrower  shall  not  make  acquisitions  which  in  the
                   aggregate  exceed  $20,000,000 and in any one instance exceed
                   $10,000,000 except certain permitted unlimited acquisitions.

                   Position:  Acquisitions   (other  than  permitted   unlimited
                              acquisitions)  in the aggregate  since the date of
                              the Agreement = _________.

               Date                 Amount                      Acquired Company
               ---------------------------                      ----------------

Permitted Unlimited Acquisition:

Date         Amount            Acquired         Principal            Line
----         ------            Company          Place of              Of
                               --------         Business            Business
                                                ---------           --------

The Borrower [is/is not] in compliance with Section 5.20.

                                       16
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<PAGE>

Additional Representations:

     There  have/have  not  been any  sale(s)  of  assets  which  would  require
     prepayment of the Notes under Section 5.2.

     There has/has not been:

         (i)       a  Change  of  Control  or  a  material   adverse  change  in
                   management  personnel  as  defined  in  Section  5.14  of the
                   Agreement;

         (ii)      a default under Section  7.1(j) or 7.1(l)  regarding a change
                   in ownership or control of the Company; or.

         (iii)     an  indemnity  claim  by  Broadcast  Partners  under  Section
                   7.1(m).

Name of Borrower:     Data Transmission Network Corporation

                      Signature: /s/ Brian L. Larson

                      Title:VP, CFO and Secretary








--------
1This section need not be completed  unless  Borrower has  subordinated  debt or
guaranty contingencies.
                                       17
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