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                                                                      Exhibit 5


                            BINGHAM, DANA & GOULD LLP
                               150 FEDERAL STREET
                        BOSTON, MASSACHUSETTS 02110-1726



                                  May 30, 1997



VideoServer, Inc.
63 Third Avenue
Burlington, MA  01803

Dear Ladies and Gentlemen:


       We have acted as counsel for VideoServer, Inc., a Delaware corporation
(the "COMPANY"), in connection with the registration under the Securities Act of
1933, as amended (the "SECURITIES ACT"), of 223,881 shares of the Company's
Common Stock, par value $.01 per share (the "SHARES"), pursuant to a
Registration Statement on Form S-3 (the "REGISTRATION STATEMENT"), filed with
the Securities and Exchange Commission on May 30, 1997, all of which Shares were
issued on April 28, 1997 pursuant to the terms of an Asset Purchase Agreement,
dated as of March 25, 1997 (the "ASSET PURCHASE AGREEMENT") between the Company
and Promptus Communications, Inc.

       As such counsel, we have reviewed the corporate proceedings of the
Company with respect to the authorization of the issuance of the Shares. We have
also examined and relied upon originals or copies, certified or otherwise
identified or authenticated to our satisfaction, of such corporate records,
instruments, agreements or other documents of the Company, and certificates of
officers of the Company as to certain factual matters, and have made such
investigation of law and have discussed with officers and representatives of the
Company such questions of fact, as we have deemed necessary or appropriate to
enable us to express the opinions rendered hereby.

       In our examination, we have assumed the genuineness of all signatures,
the conformity to originals of all documents reviewed by us as copies, the
authenticity and completeness of all original documents reviewed by us in
original or copy form and the legal competence of each individual executing a
document.

       We have also assumed that the Shares were issued and delivered in
accordance with the terms of the Asset Purchase Agreement. As to all matters of
fact (including without limitation the value placed upon the assets acquired in
consideration for the Shares pursuant to the Asset Purchase Agreement), we have
relied entirely upon the determinations, representations and statements of the
Company; and we have assumed, without independent inquiry, the accuracy of all
such determinations, representations and statements.

       This opinion is limited solely to the Delaware General Corporation Law as
applied by courts located in Delaware.




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VideoServer, Inc.
May 30, 1997
Page 2


      Based upon and subject to the foregoing, we are of the opinion that the
Shares are validly issued, fully paid and non-assessable.

      We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to this firm under the heading
"Certain Legal Matters" in the Prospectus included in the Registration
Statement.



                                    Very truly yours,


                                    /s/ Bingham, Dana & Gould LLP



                                    BINGHAM, DANA & GOULD LLP