Exhibit 5
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                                SECOND AMENDMENT
                                       TO
                                RIGHTS AGREEMENT
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         This SECOND AMENDMENT TO RIGHTS AGREEMENT  ("Amendment") is dated as of
March 24, 1999,  and is entered into by and between  Data  Transmission  Network
Corporation,  a Delaware  corporation  ("DTN"), and First National Bank of Omaha
("Rights Agent").

                                    RECITALS:

         A. DTN and Rights Agent are all of the present  parties to that certain
Rights  Agreement  dated as of August 29, 1997, as amended by First Amendment to
Rights  Agreement  dated as of March 4,  1999  (as  amended,  the  "Agreement").
Capitalized terms not defined in this Amendment shall have the meanings given to
such defined terms in the Agreement.

         B. In accordance  with the  provisions of Section 27 of the  Agreement,
the members of the Board of  Directors of DTN (which also  presently  constitute
the Continuing  Directors) have  unanimously  approved this  Amendment,  and the
Secretary of DTN has delivered to the Rights Agent a certificate  to such effect
and has directed  the Rights Agent to execute this  Amendment as provided in the
Agreement.

         NOW, THEREFORE, in consideration of the mutual covenants and agreements
set forth therein and herein, the parties hereto agree as follows:

         1. Amendment to Agreement.  Effective immediately,  Section 7(a) of the
Agreement  is  amended by  deleting  the date of August 29,  2007  (referred  to
therein as the Final  Expiration  Date) and  substituting  therefore the date of
March 24, 1999. Accordingly, the Expiration Date becomes March 24, 1999, and the
Rights are no longer exercisable.

         2. Binding  Effect.  This Amendment  shall be binding upon and inure to
the  benefit  of DTN and  Rights  Agent  and  their  respective  successors  and
permitted assigns.

         3. Superseding.  From and after the date hereof,  all references to the
Agreement shall mean the Agreement, as amended by this Amendment.

         4.  Confirmation.  Except  as  otherwise  expressly  set  forth in this
Amendment,  the  Agreement is hereby  ratified and confirmed and remains in full
force and effect.

         5.  Counterparts.  This  Amendment  may be  executed  in any  number of
counterparts,  all of which taken  together  shall  constitute  one and the same
instrument  and any of the parties  hereto may execute this Amendment by signing
any such counterpart.
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         IN WITNESS WHEREOF,  the parties have executed this Amendment as of the
date and year first above written.

                                   DATA  TRANSMISSION  NETWORK  CORPORATION


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


                                         FIRST NATIONAL BANK OF OMAHA,
                                         as Rights Agent


                                          By:   /s/  John E. Lenihan
                                                -----------------------
                                                Name: John E. Lenihan
                                                     Title: Trust Officer

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