STOCK PURCHASE AGREEMENT

         STOCK PURCHASE  AGREEMENT (the "Agreement") dated as of March 30, 1998,
by and among DATA  TRANSMISSION  NETWORK  CORPORATION,  a  Delaware  corporation
("Buyer"),  and the persons listed in Schedule 1 attached hereto  (collectively,
the "Sellers" and individually, a "Seller").

         WHEREAS,  each Seller is the owner,  beneficially and of record, of the
number of shares of the Common Stock of Kavouras,  Inc., a Minnesota corporation
(the "Company"),  set forth opposite his, her or its name on Schedule 1 attached
hereto,  and Sellers are the owners, in the aggregate,  of all of the issued and
outstanding capital stock of the Company; and

         WHEREAS, Buyer wishes to purchase from Sellers and Sellers wish to sell
to Buyer all of the issued and outstanding capital stock of the Company upon and
subject to the terms and conditions set forth herein.

         NOW,  THEREFORE,  in  consideration  of the  premises  and  the  mutual
representations,  warranties and agreements herein contained,  Buyer and Sellers
agree as follows:

                                    ARTICLE I
                                 SALE OF SHARES

         1.01 Sale of Shares. Subject to the terms and conditions herein stated,
each Seller agrees to sell, assign, transfer and deliver to Buyer on the Closing
Date (as defined herein),  the respective  shares of Common Stock of the Company
set forth  opposite  his,  her or its name on  Schedule 1 attached  hereto  (the
"Shares"),  and Buyer  agrees to purchase the Shares from Sellers on the Closing
Date. The certificates  representing the Shares shall be duly endorsed in blank,
or  accompanied  by stock powers duly  executed in blank,  by Sellers,  with all
signatures guaranteed by a state or national bank.

         1.02  Price.  In full  consideration  for the  purchase by Buyer of the
Shares,  Buyer  shall pay to each Seller on the  Closing  Date,  and each Seller
agrees to accept  from  Buyer as the  entire  purchase  price for such  Seller's
Shares,  the amount set forth opposite such Seller's name in Schedule 1 attached
hereto,  being an aggregate  amount of Sixteen  Million  Four  Hundred  Thousand
Dollars ($16,400,000).

         1.03 Closing.  Subject to Section 7.01 hereof,  the sale referred to in
Section 1.01 (the "Closing") shall take place at the offices of Faegre & Benson,
LLP, Minneapolis, Minnesota, on such date as the parties hereto shall by written
instrument  designate,  but no later than ten (10) days after the later to occur
of (i) the  expiration or termination  of all  applicable  waiting  periods with
respect to each of the antitrust  filings  referred to in Section 5.01(b) hereof
(including  any  extensions  thereof) or (ii) the  receipt of all FCC  approvals
referred to in Section 5.01(c). Such time and date are herein referred to as the
"Closing Date".

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                                   ARTICLE II
                    REPRESENTATIONS AND WARRANTIES OF SELLERS

         As of the date hereof (except as otherwise  specified herein and except
as set  forth in the  disclosure  schedule  accompanying  this  Agreement)  (the
"Disclosure Schedule") each Seller severally represents and warrants to Buyer as
follows  (provided,  however,  that each Seller so represents  and warrants only
with respect to that Seller and not with respect to any other Seller):

         2.01 Title to Stock.

         Each Seller (i) has good and valid title,  beneficially  and of record,
to the  respective  Shares set forth opposite his, her or its name on Schedule 1
attached hereto, free and clear of all liens, encumbrances and rights of others,
(ii) is in  rightful  possession  of duly  and  validly  authorized  and  issued
certificates evidencing his, her or its ownership of record of the Shares, (iii)
has full right,  power and  authority to sell,  transfer,  convey and deliver to
Buyer,  in accordance  with the terms of this  Agreement,  good and valid title,
beneficially  and of record,  to all of such Shares being sold by such Seller to
Buyer hereunder,  free and clear of all liens, encumbrances and rights of others
and (iv) does not own any other  shares of capital  stock of the  Company  other
than the shares set forth  opposite  his, her or its name on Schedule 1 attached
hereto and does not have the right to purchase or receive any additional  shares
of capital stock of the Company. Except for the sale to Buyer as contemplated by
this  Agreement,  there are no  outstanding  options,  warrants,  calls or other
rights to subscribe  for or purchase or acquire any capital stock of the Company
from the Sellers.

         2.02  Authority  Relative  to the  Transactions  Contemplated  by  this
Agreement.   Each  Seller  has  all  necessary  power,  capacity  and  authority
(corporate or otherwise) to execute and deliver this Agreement and to consummate
the  transactions  contemplated  hereby.  The  execution  and  delivery  of this
Agreement and the consummation of the transactions contemplated hereby have been
duly and validly authorized on behalf of all Sellers and no other proceedings on
behalf of Sellers are  necessary  to approve and  authorize  the  execution  and
delivery of this Agreement and the consummation of the transactions contemplated
hereby.  This  Agreement  has been duly and validly  executed  and  delivered by
Sellers,  and  (assuming the valid  execution and delivery of this  Agreement by
Buyer) constitutes a valid and binding agreement of Sellers, enforceable against
Sellers  in  accordance  with its  terms,  subject  to  bankruptcy,  insolvency,
reorganization,  moratorium and other laws of general applicability  relating to
or affecting creditors' rights and to general principles of equity.

         2.03  Consents and Approval;  No  Violation.  Neither the execution and
delivery of this Agreement by Sellers,  nor the  consummation  by Sellers of the
transactions  contemplated  hereby,  nor  compliance  by  any  Seller  with  the
provisions  hereof,  will (i) conflict  with or breach any trust  agreement  (or
other  similar  governing  documents)  of any Seller;  (ii)  violate or breach a
provision of, or  constitute a default (or an event which,  with notice or lapse
of time or both would constitute a default) under, any of the terms,  covenants,
conditions or provisions of any note, bond, mortgage,  indenture, deed of trust,
license,  franchise,  permit,  lease,  contract,  agreement or other instrument,
commitment or obligation to which any Seller is a party,  or by which any Seller

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or any of their  respective  properties or assets may be bound,  except for such
breaches  or  defaults  which when  considered  together  do not have a material
adverse  effect on the  transactions  contemplated  by this  Agreement or on the
assets,  liabilities,  business or financial  condition of the Company; or (iii)
assuming   compliance  with  all  antitrust  laws,   violate  any  order,  writ,
injunction,   decree,  judgment,   statute,  law  or  ruling  of  any  court  or
governmental authority applicable to any Seller or any of their material assets,
except for violations  which, when considered  together,  do not have a material
adverse  effect on the  transactions  contemplated  by this  Agreement or on the
assets, liabilities,  business or financial condition of the Company, taken as a
whole.

         2.04 Brokers and  Finders.  No Seller has employed any broker or finder
and no broker or  finder is  entitled  to any  brokerage  fees,  commissions  or
finder's fees arising from any act,  representation or promise of any of them in
connection with the transactions contemplated hereby.


                                   ARTICLE III
                     REPRESENTATIONS AND WARRANTIES OF BUYER

         As of the date hereof,  Buyer  represents and warrants to Principal and
Sellers as follows:

         3.01  Organization.  Buyer is a  corporation  duly  organized,  validly
existing and in good standing under the laws of the State of Delaware.

         3.02  Authority  Relative to this  Agreement.  Buyer has all  necessary
power,  capacity and  authority  (corporate or otherwise) to execute and deliver
this  Agreement and to consummate  the  transactions  contemplated  hereby.  The
execution  and  delivery  of  this  Agreement  and  the   consummation   of  the
transactions  contemplated  hereby have been duly and validly  authorized by the
Board of Directors of Buyer and no other proceedings on the part of Buyer or its
stockholders  are  necessary to approve and authorize the execution and delivery
of this Agreement or the consummation of the transactions  contemplated  hereby.
This  Agreement  has been duly and validly  executed and  delivered by Buyer and
(assuming  the valid  execution  and  delivery of the  Agreement  by Sellers and
Principal)  constitutes  a valid and  binding  agreement  of Buyer,  enforceable
against Buyer in accordance with its terms,  subject to bankruptcy,  insolvency,
reorganization,  moratorium and other laws of general applicability  relating to
or affecting creditors' rights and to general principles of equity.

         3.03 Consents and  Approvals;  No Violation.  Neither the execution and
delivery  of this  Agreement  by  Buyer  nor the  consummation  by  Buyer of the
transactions  contemplated  hereby,  nor  compliance  by  Buyer  with any of the
provisions  hereof,  will (i) require Buyer to file or register with, notify, or
obtain any permit,  authorization,  consent, or approval of, any governmental or
regulatory  authority  except (A) for filings with the Federal Trade  Commission
("FTC") and with the  Antitrust  Division  of the United  States  Department  of
Justice (the "Antitrust Division") pursuant to the  Hart-Scott-Rodino  Antitrust
Improvements  Act of  1976  as  amended  (the  "HSR  Act")  and  the  rules  and
regulations  thereunder or (B) for those requirements which become applicable to
Buyer as a result  of the  specific  regulatory  status of the  Company  or as a

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result of any other facts that specifically relate to the business activities in
which the Company is or proposes to be engaged; (ii) conflict with or breach any
provision of the Certificate of Incorporation or by-laws of Buyer; (iii) violate
or breach any  provision  of, or  constitute a default (or an event which,  with
notice or lapse of time or both,  would  constitute a default) under, any of the
terms, covenants conditions or provisions of any note, bond mortgage,  indenture
deed of trust, license, franchise,  permit, lease, contract,  agreement or other
instrument,  commitment  or  obligation  to which Buyer is a party,  or by which
Buyer or any of its properties or assets may be bound, except for such breach or
default  which  would not have a  material  adverse  effect on the  transactions
contemplated  by this Agreement  taken as a whole;  or (iv) assuming  compliance
with all  antitrust  laws  (including  the HSR Act)  violate  any  order,  writ,
injunction,   decree,  judgment,   statute,  law  or  ruling  of  any  court  or
governmental  authority applicable to Buyer or any of its material assets, which
violation would have a material adverse effect on the transactions  contemplated
by this Agreement taken as a whole.

         3.04  Litigation;  Compliance  with  Law.  Buyer  is not a party to any
action or proceeding which seeks, or is subject to, any outstanding order, writ,
injunction  or  decree,   which   restrains  or  enjoins   consummation  of  the
transactions  contemplated hereby or which otherwise challenges the transactions
contemplated hereby and (ii) there is no litigation, administrative, arbitral or
other  proceeding,  or  petition or  complaint  or, to the  knowledge  of Buyer,
investigation  before any court or governmental or regulating  authority or body
pending or, to the knowledge of Buyer,  threatened  against or relating to Buyer
that  would   materially   adversely  affect  Buyer's  ability  to  perform  its
obligations pursuant to this Agreement.

         3.05 Brokers and  Finders.  Buyer has not employed any broker or finder
and no broker or  finder is  entitled  to any  brokerage  fees,  commissions  or
finder's  fees arising  from any act,  representations  or promise of Buyer,  in
connection with the transactions contemplated hereby.

         3.06 Purchase for Investment. Buyer will acquire all of the outstanding
stock of the Company to be  purchased  by it  hereunder  for its own account for
investment and not with a view toward any resale or distribution thereof.  Buyer
understands that the Shares have not been registered under the Securities Act of
1933, as amended,  or the securities  laws of any states and,  accordingly,  the
Shares  may not be  resold  by Buyer  unless  registered  under the 1933 Act and
applicable state securities laws, or sold in transactions  which are exempt from
registration thereunder.

                                   ARTICLE IV
                            COVENANTS OF THE PARTIES

         4.01 Expenses.  Whether or not the transactions contemplated hereby are
consummated,  all costs and expenses  incurred in connection with this Agreement
and the  transactions  contemplated  hereby will be paid by the respective party
that incurred such cost or expense.

         4.02  Reasonable  Best Efforts.  Subject to the terms and conditions of
this  Agreement  and except as  otherwise  provided  herein,  all of the parties
hereto will use their reasonable best efforts to take, or cause to be taken, all

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action,  and to do,  or  cause to be  done,  all  things  necessary,  proper  or
advisable under applicable laws and regulations to consummate and make effective
the transactions  contemplated by this Agreement.  In case at any time after the
Closing any further  action is  necessary or desirable to carry out the purposes
of this  Agreement  or to put Buyer in  possession  of all of the  Shares of the
Company or the Company in  possession  of all of its assets,  each party to this
Agreement  will,  or will cause its  affiliates  as the case may be, to take all
such necessary action including,  without limitation, the execution and delivery
of such further  instruments and documents as may reasonably be requested by the
parties  hereto for such  purposes  or  otherwise  to  complete  or perfect  the
transactions contemplated hereby.

         4.03 Consents.  Each of the parties hereto will use its reasonable best
efforts  to  obtain  the  written  consents  of  all  persons  and  governmental
authorities  required  to be obtained  by each such party and  necessary  to the
consummation of the transactions contemplated by this Agreement.

         4.04  Disclosure  Supplements.  From time to time prior to the Closing,
Sellers  will  promptly  supplement  or  amend  ("Disclosure  Supplements")  any
Schedule  referred to in this  Agreement  with  respect to any matter  hereafter
arising  which,  if  existing  or  occurring  at or  prior  to the  date of this
Agreement,  such party  determines  would have been  required to be set forth or
described in a Schedule or which is necessary  to correct any  information  in a
Schedule  or in any  representation  or  warranty  of any Seller  which has been
rendered inaccurate thereby. The representations and warranties of Sellers shall
be amended by the  Disclosure  Supplements  in all respects and for all purposes
other than for the purposes of  determining  satisfaction  of the  conditions to
Closing set forth in Article V.

         4.05 Public  Announcements.  Between the date of this Agreement and the
earlier of the Closing Date or the  termination  of this  Agreement  pursuant to
Section 7.01 hereof, Trusts and Buyer will consult with each other before any of
them  issues  any  press  releases  or  otherwise  makes any  public  statements
(including  statements  made to employees  of the Company)  with respect to this
Agreement and the transactions contemplated hereby.

         4.06 Transfer Taxes.  All transfer taxes  (including all stock transfer
taxes, if any) incurred in connection  with this Agreement and the  transactions
contemplated  hereby will be borne by the respective  Sellers,  and such Sellers
will,  at  their  own  expense,   file  all  necessary  tax  returns  and  other
documentation  with  respect to all such  transfer  taxes,  and,  if required by
applicable  law, the other  parties  hereto will (and will cause the Company to)
join in the execution of any such tax returns or other documentation.

         4.07 No  Solicitation.  Between  the  date of  this  Agreement  and the
earlier of the Closing Date or the  termination  of this  Agreement  pursuant to
Section  7.01  hereof,  Sellers  shall  not  initiate,  solicit,  encourage,  or
participate  in, any  discussions  with,  or  provide  any  information  to, any
corporation,  partnership,  person,  entity or group,  other  than Buyer and its
employees and agents,  concerning any merger,  consolidation,  sale of assets or
similar  transaction  involving  the  Company,  or any sale of Shares or capital
stock of the Company,  including securities convertible into or exchangeable for
such securities, by the issuer (any such transaction being referred to herein as

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an "Acquisition  Proposal").  Sellers will suspend any pre-existing  discussions
involving  any  Acquisition  Proposal and will  immediately  advise Buyer if any
Seller  receives any  Acquisition  Proposal from any  corporation,  partnership,
person, entity or group.

                                    ARTICLE V
                                   CONDITIONS

         5.01 Conditions to Each Party's  Obligations to Effect the Transactions
Contemplated  Hereby. The respective  obligations of each party hereto to effect
the transactions  contemplated  hereby shall be subject to the fulfillment at or
prior to the Closing of each of the following conditions:

         (a) No statute, rule, regulation,  executive order, decree,  injunction
or restraining order shall have been enacted,  entered,  promulgated or enforced
by any court of competent jurisdiction or governmental authority,  nor shall any
action or proceeding brought by any governmental authority or agency be pending,
which (i) prevents,  restricts or delays or seeks to prevent,  restrict or delay
the  consummation  of the  transactions  contemplated  by this Agreement or (ii)
seeks a material amount of monetary  damages in connection with the consummation
of the transactions contemplated by this Agreement.

         (b) Sellers and Buyer and any other  person (as defined in the HSR Act)
required  in  connection  with the  transactions  contemplated  hereby to file a
Notification  and Report Form for  Certain  Mergers  and  Acquisitions  with the
Antitrust  Division  and the FTC  pursuant  to the HSR Act shall  have made such
filings and all  applicable  waiting  periods  with  respect to each such filing
(including any extensions thereof) shall have expired or been terminated.

         (c) Buyer and the Company  shall have filed with the FCC all  requisite
applications  in  connection  with the  transfer of control of all  FCC-licensed
satellite  earth  station  facilities,   experimental  FCC  authorizations,  and
equipment  authorizations  currently  held by the  Company  pursuant  to the FCC
Rules, and each such application shall have been approved by the FCC.

         (d) Each  condition  to  closing  set forth in that  certain  Agreement
Regarding Stock Acquisition (the "Agreement  Regarding Stock Acquisition") among
Stephen P. Kavouras, Buyer and the trusts listed on Schedule 1 as Sellers, dated
of even date herewith, shall have been fulfilled at or prior to Closing, or such
condition  shall  have  been  waived by the party  whose  obligations  under the
Agreement Regarding Stock Acquisition were contingent upon such condition.

         5.02   Conditions  to  the   Obligations   of  Sellers  to  Effect  the
Transactions  Contemplated  Hereby.  The  obligations  of  Sellers to effect the
transactions  contemplated hereby shall be further subject to the fulfillment at
or prior to the Closing of each of the following conditions,  any one or more of
which may be waived in whole or in part by a majority of Sellers in writing:

         (a) Buyer shall have  performed  and complied in all material  respects
with all  agreements,  obligations,  conditions and covenants  contained in this
Agreement  required to be performed  and complied  with by it at or prior to the

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Closing  and all  representations  and  warranties  of Buyer  contained  in this
Agreement  shall be true and correct in all material  respects as of the date of
this  Agreement  and as of the Closing Date (as if the Closing Date was the date
of this Agreement),  and Sellers shall have received certificates to that effect
signed by the President or any Vice  President of Buyer together with such other
documents,  instruments  and  writings  required to be  delivered by Buyer at or
prior to the Closing pursuant to this Agreement or otherwise reasonably required
by Buyer in connection herewith.

         (b) Buyer shall have delivered to Sellers (i) a copy of the Certificate
of Incorporation of Buyer,  including all amendments  thereto,  certified by the
Secretary  of State of the State of  Delaware  and (ii) a  certificate  from the
Secretary of the State of Delaware to the effect that Buyer is in good  standing
in such State.

         (c) No actions or  proceedings  which  have a  material  likelihood  of
success shall have been instituted or, to the knowledge of Buyer,  threatened by
any  governmental  body  or  authority  to  restrain  or  prohibit  any  of  the
transactions contemplated hereby.

         (d)  All  material  consents,  waivers,  authorizations,  licenses  and
approvals,  if any,  necessary to permit Sellers to consummate the  transactions
contemplated by this Agreement shall have been received.

         (e) All  documents  and  instruments  to be  delivered  at  Closing  or
otherwise in connection  with the  transactions  contemplated  by this Agreement
shall be  reasonably  satisfactory  in form and  substance  to Sellers and their
counsel.

         5.03 Conditions to the Obligations of Buyer to Effect the  Transactions
Contemplated  Hereby.  The  obligations  of Buyer  to  effect  the  transactions
contemplated  hereby shall be further  subject to the fulfillment at or prior to
the Closing of each of the following conditions, any one or more of which may be
waived in whole or in part by Buyer in writing:

         (a) Sellers shall have performed and complied in all material  respects
with all  agreements,  obligations,  conditions and covenants  contained in this
Agreement  required to be performed and complied with by them at or prior to the
Closing  and all  representations  and  warranties  of Sellers set forth in this
Agreement  shall be true and correct in all material  respects as of the date of
this  Agreement and as amended by any  Disclosure  Supplements as of the Closing
Date (as if the Closing  Date was the date of this  Agreement),  and Buyer shall
have  received  certificates  to that  effect  signed  by  Sellers,  in the form
attached  hereto as Exhibit A, together with such other  documents,  instruments
and  writings  required to be delivered by Sellers or by the Company at or prior
to the Closing  pursuant to this  Agreement or otherwise  required in connection
herewith,  provided,  however,  that  if the  Disclosure  Supplements  reveal  a
material  change from the Schedules  attached  hereto at the date hereof that is
unacceptable to Buyer,  Buyer shall not be obligated to effect the  transactions
contemplated hereby.

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         (b) No action or  proceedings  which have a  reasonable  likelihood  of
success shall have been  instituted or, to the knowledge of Sellers,  threatened
by any  governmental  body or  authority  to  restrain  or  prohibit  any of the
transactions contemplated hereby.

         (c) Each  party  hereto  shall have  received  all  material  consents,
waivers,   approvals,   licenses  or  other  authorizations  required  from  any
governmental  or  non-governmental  entity  for  the  execution,   delivery  and
performance of this Agreement by the parties hereto.

         (d) No injunction or other court order  requiring  that any part of the
business  or assets of the  Company be held  separate  or  divested  or that any
business or assets of Buyer or any  affiliate of Buyer be divested,  or imposing
or involving  any  conditions on Buyer or its  affiliates or the Company,  which
could be reasonably  expected to have a material  adverse  effect on the assets,
liabilities,  business, financial condition,  prospects or results of operations
of either Buyer or any affiliate of Buyer on the one hand, or the Company on the
other hand, shall be in effect and no proceedings shall be pending by or before,
or  threatened  in  writing  by or  before,  any  governmental  body or court of
competent jurisdiction with respect thereto.

         (e) Other than as disclosed in the Disclosure Schedule, there shall not
be in effect at the Closing  Date any  contractual  provisions  restricting  the
ability of the  Company or any  affiliate  thereof to conduct  any  business  or
compete  with any person or  restricting  the area in which it may  conduct  any
business.

         (f) Buyer and its counsel shall have approved (which approval shall not
be  unreasonably  withheld) (i) the form of stock power or other  instruments of
transfer to be  delivered  to Buyer at the Closing and (ii) all other  documents
and  instruments to be delivered at the Closing or otherwise in connection  with
the transactions contemplated by this Agreement.


                                   ARTICLE VI
                          SURVIVAL AND INDEMNIFICATION

         6.01  Survival  of  Representations,   Warranties  and  Covenants.  All
covenants and  agreements of any party hereto set forth herein shall survive the
Closing for the period provided for in such covenant or, if not so provided, for
a period of one year. The  representations and warranties set forth herein shall
survive the Closing and shall remain in effect for a period of one year from the
Closing Date.

         6.02 Post-Closing Indemnification. (a) From and after the Closing Date,
Buyer  shall  defend,  indemnify  and hold  harmless  Sellers  and their  heirs,
trustees,  successors and assigns  against and in respect of any and all losses,
actions, suits,  proceedings,  claims,  liabilities,  damages, causes of action,
demands,  assessments,  judgments,  and investigations and any and all costs and
expenses  paid  to  third  parties,  including  without  limitation,  reasonable
attorneys' fees and expenses, suffered by any of them as a result of, or arising
from, any inaccuracy in or breach of or omission from any of the representations
or warranties made by Buyer in Article III of this Agreement or pursuant hereto,

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or any non-fulfillment,  partial or total, of any of the covenants or agreements
made by Buyer in this Agreement to the extent not waived by Sellers in writing.

         (b)  From and  after  the  Closing  Date,  each  Seller  shall  defend,
indemnify  and hold  harmless  the Buyer  and its  subsidiaries  (including  the
Company)  and  each  of  their  successors,  assigns,  officers,  directors  and
employees (the "Buyer  Indemnitee  Group") against and in respect of any and all
losses, actions, suits,  proceedings,  claims,  liabilities,  damages, causes of
action,  demands,  assessments,  judgments,  and  investigations and any and all
costs  and  expenses  paid  to  third  parties,  including  without  limitation,
reasonable  attorneys' fees and expenses suffered by any of them as a result of,
or arising  from,  any  inaccuracy  in or breach of or omission  from any of the
representations  or  warranties  made  by  such  Seller  in  Article  II of this
Agreement or pursuant hereto, or any  non-fulfillment,  partial or total, of any
of the covenants or agreements made by such Seller in this Agreement.

         (c) If a claim by a third party is made against an  indemnified  party,
and if such party  intends to seek  indemnity  with respect  thereto  under this
Article VI, the  indemnified  party shall  promptly  (and in any case within ten
days of such claim  being  made)  notify the  indemnifying  party of such claim,
provided,  however,  that the failure to so notify the indemnifying  party shall
not discharge the  indemnifying  party of its obligations  hereunder except that
the indemnifying  party shall not be liable for default judgments or any amounts
related  thereto  if the  indemnified  party  shall  not  have so  notified  the
indemnifying party.  Subject to the following  sentence,  the indemnifying party
shall have thirty days after  receipt of such notice to  undertake,  conduct and
control,  through  counsel of its own  choosing  (which is  satisfactory  to the
indemnified party) the settlement or defense thereof,  and the indemnified party
shall cooperate with it in connection  therewith (provided that the indemnifying
party shall permit the  indemnified  party to participate in such  settlement or
defense through counsel chosen by the indemnified party,  provided that the fees
and expenses of such counsel  shall be borne by the  indemnified  party) and the
indemnifying  party shall promptly  reimburse the indemnified party for the full
amount  of any loss  resulting  from  such  claim and all  related  expenses  as
incurred  by  the   indemnified   party  within   limits  of  this  Article  VI.
Notwithstanding  anything herein to the contrary,  the  indemnified  party shall
have the right to conduct and control the defense of any such claim in the event
that such claim (including a claim for equitable  relief) or the continuation of
such claim  could  reasonably  be expected to  materially  adversely  affect the
business,  results  of  operations,  prospects  or  financial  condition  of the
indemnified party or any of its affiliates,  provided, however, that (i) in such
event the  indemnified  party's  selection  of  counsel  shall be subject to the
approval of the  indemnifying  party,  which approval shall not be  unreasonably
withheld,  and (ii) the indemnified party may not settle any claim for an amount
in excess of  $25,000  or  consent to any  settlement  which  imposes  equitable
remedies on the indemnifying  party or its affiliates  without the prior consent
of the  indemnifying  party,  which consent shall not be unreasonably  withheld,
unless the indemnified party agrees to waive any right to indemnity  therefor by
the  indemnifying   party.  If  the  indemnifying  party  does  not  notify  the
indemnified  party  within  thirty  days after the  receipt  of the  indemnified
party's notice of a claim of indemnity hereunder that it elects to undertake the
defense thereof or if the  indemnifying  party is not reasonably  contesting the
claim in good  faith,  the  indemnified  party  shall have the right to contest,
settle or compromise the claim in the exercise of its reasonable  judgment,  and

                                       9
                                    - 108 -
<PAGE>

all losses incurred by the indemnified party, including all fees and expenses of
counsel for the indemnified party, shall be paid by the indemnifying party.

         (d) Claims for  indemnification  made under this  Section 6.02 shall be
made within a period of one year from the Closing Date.

         6.03 Limitation on Indemnification.  (a) Notwithstanding the provisions
of Section  6.02(a)  hereof,  Buyer shall not be obligated to indemnify and hold
harmless Sellers until the aggregate of all claims for which  indemnification is
sought against Buyer under Section 6.02(a) of this Agreement and Section 6.02(b)
of the Agreement Regarding Stock Acquisition  exceeds, in the aggregate,  Eighty
Thousand  Dollars  ($80,000),  and then only as to the amount by which aggregate
claims  thereunder exceed $80,000.  Buyer's aggregate  liability with respect to
the  indemnification  contained in Section 6.02(a) of this Agreement and Section
6.02(b)  of  the  Agreement   Regarding  Stock   Acquisition  shall  not  exceed
$2,000,000,  and each party hereto  waives (on its own behalf,  and on behalf of
all   indemnified   persons  named   hereunder   benefiting  from  such  party's
indemnification) any and all rights, claims and causes of action that it or such
persons may have  against  the  indemnifying  party  under such  indemnification
provisions to the extent such rights, claims and causes of action would or could
result in aggregate liability of the indemnifying party in excess of $2,000,000.

         (b)  Notwithstanding  the  provisions of Section  6.02(b)  hereof,  the
aggregate  liability  under this  Agreement  of each Seller shall not exceed the
amount set forth  opposite  such  Seller's  name in Schedule 1 attached  hereto,
being the purchase price for such Seller's Shares.

         (c) Except for liability provided for in Section 7.02(b) hereof and the
remedy of specific  performance  provided for in Section 8.12 hereof, each party
hereto  acknowledges  and agrees that his, her or its sole and exclusive  remedy
with  respect  to any and all  claims  relating  to the  subject  matter of this
Agreement shall be pursuant to the indemnification  provisions set forth in this
Article VI. In furtherance of the foregoing,  each party waives,  to the fullest
extent permitted under applicable law, any and all rights,  claims and causes of
action that it may have against the other party  arising under or based upon any
federal, state or local statute, law, ordinance,  rule or regulation, or arising
under or based upon common law or  otherwise,  except to the extent  provided in
this Article VI.

                                   ARTICLE VII
                           TERMINATION AND ABANDONMENT

         7.01 Termination. This Agreement may be terminated at any time prior to
the Closing:

         (a)  by the mutual consent of Buyer and a majority of Sellers; or

         (b) by either  Buyer or a majority of Sellers if the Closing  shall not
have occurred on or before December 31, 1998 or such later date as may be agreed
upon by Buyer, and a majority of Sellers; or

                                       10
                                    - 109 -
<PAGE>

         (c) upon the termination of the Agreement Regarding Stock Acquisition.

         7.02 Procedure and Effect of  Termination.  In the event of termination
of this Agreement and abandonment of the transactions contemplated hereby by any
or all of the parties  pursuant to Section 7.01,  written  notice  thereof shall
forthwith be given to the other  parties to this  Agreement  and this  Agreement
shall  terminate and the  transactions  contemplated  hereby shall be abandoned,
without  further  action by any of the  parties  hereto.  If this  Agreement  is
terminated as provided herein:

         (a) the parties hereto will promptly redeliver to the Sellers or Buyer,
as the case may be, all documents,  work papers and other materials of any other
party relating to the transactions  contemplated hereby, whether obtained before
or after the execution hereof; and

         (b) no party hereto shall have any  liability or further  obligation to
any other party to this  Agreement  pursuant to this  Agreement  except (i) with
respect to Section 4.01, and (ii) solely with respect to  terminations  pursuant
to Section 7.01(b), any party whose material breach of any covenant or agreement
hereunder shall have resulted in the failure of the transactions contemplated by
this Agreement to close, shall be liable for breach of contract or otherwise, to
the extent provided by law (it being  understood,  however,  that any matter set
forth on a Disclosure Supplement hereunder shall not be construed as a breach or
default of this  Agreement);  provided,  however,  that this subsection (b) (ii)
shall not be construed to limit the remedies otherwise available with respect to
such defaulting party.


                                  ARTICLE VIII
                            MISCELLANEOUS PROVISIONS

         8.01  Amendment  and  Modification.  This  Agreement  may  be  amended,
modified or supplemented only by written agreement of Buyer and Sellers.

         8.02 Waiver of Compliance;  Consents.  Except as otherwise  provided in
this Agreement, any failure of any of the parties to comply with any obligation,
covenant,  agreement or  condition  herein may be waived by the party or parties
entitled to the  benefits  thereof  only by a written  instrument  signed by the
party  granting  such  waiver,  but such waiver or failure to insist upon strict
compliance  with such  obligation,  covenant,  agreement or condition  shall not
operate as a waiver of, or estoppel  with  respect to, any  subsequent  or other
failure.  Whenever this Agreement requires or permits consent by or on behalf of
any party hereto,  such consent shall be given in writing in a manner consistent
with the  requirements  for a waiver of  compliance as set forth in this Section
8.02.

         8.03  No  Third  Party  Beneficiaries.   Except  as  provided  in  this
Agreement,  nothing in this Agreement shall confer any rights upon any person or
entity  which  is not a  party  or a  permitted  assignee  of a  party  to  this
Agreement.

                                       11
                                    - 110 -
<PAGE>

         8.04  Notices.  All  notices,   requests,  claims,  demands  and  other
communications  hereunder  shall be in writing  and shall be deemed to have been
duly given when  delivered  in person,  by cable,  telegram or telex,  telecopy,
courier,  express mail delivery  service,  or by  registered  or certified  mail
(postage  prepaid,  return  receipt  requested)  to the  respective  parties  as
follows:

         (a)      if to Sellers, to their respective addresses
                  set forth on Schedule 1 of this Agreement;

         (b)      if to Buyer, to:

                  Data Transmission Network Corporation
                  9110 West Dodge Road
                  Suite 200
                  Omaha, Nebraska  68114
                  Attn: Greg T. Sloma, President
                  Facsimile:  (402) 390-7188

                  with a copy to:
                  Abrahams Kaslow & Cassman
                  8712 West Dodge Road
                  Suite 300
                  Omaha, Nebraska  68114
                  Attn: R. Craig Fry
                  Facsimile:  (402) 392-0816

or to such  other  address  as the  person  to whom  notice  is  given  may have
previously  furnished  to the others in  writing  in the manner set forth  above
(provided  that  notice of any change of address  shall be  effective  only upon
receipt thereof).

         8.05 Assignment.  This Agreement and all of the provisions hereof shall
be  binding  upon and  inure to the  benefit  of the  parties  hereto  and their
respective  successors and permitted assigns.  Neither this Agreement nor any of
the rights,  interests or obligations  hereunder  shall be assigned by any party
hereto  without  the  prior  written  consent  of the other  parties,  except as
provided in Section 8.13.

         8.06 Governing Law;  Consent to  Jurisdiction.  This Agreement shall be
governed by the law of the State of Nebraska as to all matters,  including,  but
not limited to,  matters of  validity,  construction,  effect,  performance  and
remedies without giving effect to the principles of choice of law thereof.

         8.07  Counterparts.  This  Agreement  may be  executed  in two or  more
counterparts,  each of  which  shall be  deemed  an  original,  but all of which
together shall constitute one and the same instrument.

                                       12
                                    - 111 -
<PAGE>

         8.08 Interpretation. The article and section headings contained in this
Agreement are solely for the purpose of reference, are not part of the agreement
of the parties and shall not in any way affect the meaning or  interpretation of
this Agreement.

         8.09 Entire  Agreement.  This Agreement,  including the Exhibits hereto
and the  agreements  (including  the  Agreement  Regarding  Stock  Acquisition),
documents,  schedules,  certificates and instruments referred to herein embodies
the entire  agreement and  understanding of the parties hereto in respect of the
transactions  contemplated  by  this  Agreement.   There  are  no  restrictions,
promises,  representations,  warranties,  covenants or undertakings,  other than
those  expressly  set forth or  referred to herein or  therein.  This  Agreement
supersedes  all prior  agreements  and  understandings  between the parties with
respect to such transactions.

         8.10  Certain Definitions.

         (a) An "affiliate" of a person shall mean any person which, directly or
indirectly,  controls,  is controlled by, or is under common control with,  such
person.

         (b) The term "control" (including,  with correlative meaning, the terms
"controlled  by" and "under common control  with"),  as used with respect to any
person, means the possession,  directly or indirectly, of the power to direct or
cause the  direction of the  management  and  policies of such  person,  whether
through the ownership of voting securities or by contract or otherwise.

         (c)  The  term  "person"  shall  mean  and  include  an  individual,  a
partnership,  a limited liability  company,  a joint venture,  a corporation,  a
trust,  an  unincorporated  organization  and a government or any  department or
agency thereof.

         (d)   The term "day" shall mean a calendar day unless otherwise stated.

         (e) The term  "subsidiary"  when used in  reference to any other person
shall mean any  corporation  of which  outstanding  securities  having  ordinary
voting power to elect a majority of the Board of  Directors of such  corporation
are owned directly or indirectly by such other person.

         (f) Whenever any representation or warranty contained in this Agreement
is qualified by reference to the  knowledge,  information  or belief of a party,
such party confirms that it has made due and diligent  inquiry as to the matters
that are the subject of such representation and warranty.

         8.11  Severability.  The parties hereto acknowledge that the provisions
of this Agreement are reasonable under the circumstances.  Any provision of this
Agreement that is prohibited or unenforceable  in any jurisdiction  shall, as to
such  jurisdiction,  be  ineffective  to  the  extent  of  such  prohibition  or
unenforceability   without  invalidating  the  remaining  provisions  hereof  or
affecting  the  validity  or  enforceability  of such  provisions  in any  other
jurisdiction.

                                       13
                                    - 112 -
<PAGE>

         8.12 Specific Performance.  Each of the parties hereto acknowledges and
agrees that the other parties hereto would be  irreparably  damaged in the event
any of the  provisions of this  Agreement  are not performed in accordance  with
their specific terms or are otherwise breached. Accordingly, each of the parties
hereto agrees that they each shall be entitled to an  injunction or  injunctions
to  prevent  breaches  of the  provisions  of  this  Agreement  and  to  enforce
specifically  this Agreement and the terms and  provisions  hereof in any action
instituted  in any  court of the  United  States  or any  state  thereof  having
personal  and subject  matter  jurisdiction,  in addition to any other remedy to
which such party may be entitled at law or in equity. In the event of any action
or  proceeding  to  enforce  the terms and  conditions  of this  Agreement,  the
prevailing  party  shall be entitled to an award of  reasonable  attorneys'  and
expert's fees and costs in addition to such other relief as may be granted.

         8.13  Effectiveness.  This Agreement shall not become  effective unless
all Sellers named herein (other than Paul Post and his spouse) have executed and
delivered  this Agreement  prior to the Closing.  If Paul Post does not become a
party prior to Closing,  then the aggregate  purchase price for the Shares shall
be  reduced by the amount  set forth  opposite  his name on  Schedule 1 attached
hereto and, at the option of Buyer in its sole discretion, Buyer may assign this
Agreement to a wholly-owned  subsidiary of Buyer  immediately  prior to Closing;
provided,  however, that such assignment shall not release Buyer from any of its
obligations and liabilities under this Agreement.

         IN WITNESS  WHEREOF,  Sellers  and Buyer have  signed,  or caused  this
Agreement to be signed by their respective representatives,  as the case may be,
as of the date first above written.

                                          DATA TRANSMISSION NETWORK
                                          CORPORATION


                                          By: /s/ Greg T. Sloma
                                              ----------------------------
                                              Greg T. Sloma, President


                                          STEPHEN P. KAVOURAS REVOCABLE
                                          TRUST UNDER AGREEMENT DATED
                                          SEPTEMBER 13, 1995

                                          By: /s/ Stephen P. Kavouras, Trustee
                                              --------------------------------
                                              Stephen P. Kavouras, Trustee
                                       14
                                    - 113 -
<PAGE>

                                          IRREVOCABLE GST TRUST FOR STEPHEN
                                          P. KAVOURAS UNDER AGREEMENT
                                          DATED JULY 29, 1997


                                          By ______________________________
                                             Stephen P. Kavouras, Trustee


                                          And ____________________________
                                              Laura Burrow, Trustee


                                              ---------------------------------
                                              Walter A. Lyons


                                              ---------------------------------
                                              Darold L. Holden


                                              ---------------------------------
                                              Mavis Holden

                                              ---------------------------------
                                              Mrs. Michael Govotas


                                              ---------------------------------
                                              Daniel Andrew Kavouras


                                              ---------------------------------
                                              Larry Barnet Kavouras


                                              ---------------------------------
                                              Patricia K. Kavouras


                                              ---------------------------------
                                              Myron Hjermstead, Jr.


                                       15
                                    - 114 -
<PAGE>

                                              ---------------------------------
                                              Darlene Hjermstead


                                              ---------------------------------
                                              Paul Post


                                              ---------------------------------
                                              __________  Post


                                              ---------------------------------
                                              Dennis K. Sanford


                                              ---------------------------------
                                              Lynn M. Sanford


                                       16
                                     - 115 -
<PAGE>




                                   SCHEDULE 1


<TABLE>
<CAPTION>

   Name and                                       Number of                               Portion of
Address Of Seller                                Shares Owned                           Purchase Price


<S>                                                    <C>                              <C>        
Stephen P. Kavouras,                                   100                              $10,552,278
Trustee of the Stephen
P. Kavouras Revocable
Trust under Agreement
dated September 13, 1995
11400 Rupp Drive
Burnsville, MN  55337

Stephen P. Kavouras and                                 30                              $ 3,165,683
Laura Burrow, as Trustees
of the Irrevocable GST
Trust for Stephen P.
Kavouras under Agreement
dated July 29, 1997
11400 Rupp Drive
Burnsville, MN  55337

Walter A. Lyons, Ph.D., CCM                              7                              $   738,660
46050 Weld County Road 13
Ft. Collins, CO  80524

Darold L. Holden                                         5                              $   527,614
4232 Black Hawk Road
Eagan, MN  55122

Darold  and Mavis Holden                                 1/3                            $    35,174
4232 Black Hawk Road
Eagan, MN  55122

Mrs. Michael Govotas                                     4                                  422,091
620 Lynwood Drive
Benton Harbor, MT  49022


Daniel Andrew Kavouras                                   2                              $   211,046
6035 Forest Circle Drive
Brooksville, FL  34601

                                       17
                                    - 116 -
<PAGE>

Larry Barnet Kavouras                                    2                              $   211,046
1906 N. 159th East
Wichita, KS  67230

Patricia K. Kavouras                                     2                              $   211,046
67 South Peak Road
Boulder, CO  80302

Myron and Darlene                                        1 1/12                         $   114,316
  Hjermstead, Jr.
8340 Eastwood Drive, N.E.
Mounds View, MN  55112

Paul Post                                                1                              $   105,523
2646 Richardson Street
Madison, WI  53711

Dennis K. and Lynn M. Sanford                            1                              $   105,523
                                                       ---                              -----------
13945 Thunderbird Road N
Prescott, AZ  86301

TOTALS                                                 155 5/12                         $16,400,000


</TABLE>


                                       18
                                    - 117 -
<PAGE>




                                    EXHIBIT A



                               CLOSING CERTIFICATE


 The  undersigned,  being a Seller under that certain Stock  Purchase  Agreement
(the "Stock Purchase  Agreement")  dated March ___, 1998, among the shareholders
of Kavouras,  Inc. (the "Company"),  and Data Transmission  Network  Corporation
(the "Buyer"), do hereby certify to the Buyer as follows:

         1. The undersigned has performed and complied in all material  respects
with all  agreements,  obligations,  conditions  and covenants  contained in the
Stock  Purchase  Agreement  required to be performed  and  complied  with by the
undersigned  at or  prior  to  the  date  hereof  and  all  representations  and
warranties of the undersigned set forth in the Stock Purchase Agreement are true
and  correct in all  material  respects  as if made on and as of this  date,  as
amended by any Disclosure Supplements.

         2. This  certificate is given pursuant to Section  5.03(a) of the Stock
Purchase Agreement.


         DATED as of ______________, 1998

                                           SELLER:


                                           ---------------------------------

                                           Printed Name:_____________________


                                       19
                                    - 118 -