Exhibit 8.1

                                 Ropes & Gray
                            One International Plaza
                         Boston, Massachusetts   02110


                                                  June 24, 1996

FTP Software, Inc.
100 Brickstone Square, Fifth Floor
Andover, Massachusetts 01810

Firefox Acquisition Corp.
100 Brickstone Square, Fifth Floor
Andover, Massachusetts 01810

Ladies and Gentlemen:

     This opinion is being delivered to you in connection with the filing of a
registration statement on Form S-4 of a joint proxy statement/prospectus, and
pursuant to Section 6.3(d) of the Amended and Restated Agreement and Plan of
Merger dated May 21, 1996 (the "Merger Agreement") among FTP Software, Inc., a
Massachusetts corporation ("FTP Software"), Firefox Acquisition Corp., a
Delaware corporation and a wholly-owned subsidiary of FTP Software ("Sub"), and
Firefox Communications, Inc., a Delaware corporation ("Firefox"). Pursuant to
the Merger Agreement, Sub will merge with and into Firefox (the "Merger"), and
Firefox will become a wholly-owned subsidiary of FTP Software.

     Except as otherwise provided, capitalized terms referred to herein have the
meanings set forth in the Merger Agreement.  All section references, unless
otherwise indicated, are to the Internal Revenue Code of 1986, as amended (the
"Code").

     We have acted as legal counsel to Firefox in connection with the Merger.
As such, and for the purpose of rendering this opinion, we have examined and are
relying upon (without any independent investigation or review thereof) the truth
and accuracy, at all relevant times, of the statements, covenants,
representations and warranties contained in the following documents (including
all schedules and exhibits thereto):

     1.   The Merger Agreement;

     2.   Representations made to us by Firefox;

 
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     3.   Representations made to us by FTP Software and Sub;

     4.   The registration statement on Form S-4 of a Joint Proxy
Statement/Prospectus of Firefox, FTP Software, and Sub (the "Registration
Statement");

     5.   Representations and covenants of certain shareholders of Firefox in
"Stockholder Agreements"; and

     6.   Such other instruments and documents related to the formation,
organization and operation of Firefox, FTP Software and Sub or to the
consummation of the Merger and the transactions contemplated thereby as we have
deemed necessary or appropriate.

     In connection with rendering this opinion, we have assumed or obtained
representations (and are relying thereon, without any independent investigation
or review thereof) that:

     1.  Original documents (including signatures) are authentic, documents
submitted to us as copies conform to the original documents, and there has been
(or will be by the Effective Time of the Merger) due execution and delivery of
all documents where due execution and delivery are prerequisites to
effectiveness thereof.

     2.  The Merger will be consummated pursuant to applicable state law.

     3.  Any representation or statement made "to the best of knowledge" or
similarly qualified is correct without such qualification.  As to all matters in
which a person or entity making a representation referred to above has
represented that such person or entity either is not a party to, does not have,
or is not aware of, any plan or intention, understanding or agreement, there is
in fact no such plan, intention, understanding or agreement.

     Based on our examination of the foregoing items and subject to the
assumptions, exceptions, limitations and qualifications set forth herein, we are
of the opinion that for federal income tax purposes, the Merger will constitute
a "reorganization" as defined in Section 368(a) of the Code.

     In addition to the assumptions set forth above, this opinion is subject to
the exceptions, limitations and qualifications set forth below.

     1.  This opinion represents and is based upon our best judgment regarding
the application of federal income tax laws arising under the Code, existing
judicial decisions, administrative regulations and published rulings and
procedures.  Our opinion is not binding upon the Internal Revenue Service or the
courts, and the Internal Revenue Service is not

 
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precluded from successfully asserting a contrary position.  Furthermore, no
assurance can be given that future legislative, judicial or administrative
changes, on either a prospective or retroactive basis, would not adversely
affect the accuracy of the conclusions stated herein. Nevertheless, we undertake
no responsibility to advise you of any new developments in the application or
interpretation of the federal income tax laws.

     2.  No opinion is expressed as to any matter not specifically addressed
above.  Also, no opinion is expressed as to the tax consequences of the
transaction under any foreign, state, or local tax law.

     3.  No opinion is expressed as to any transaction other than the Merger as
described in the Merger Agreement or to any transaction whatsoever, including
the Merger, if all the transactions described in the Merger Agreement are not
consummated in accordance with the terms of such Merger Agreement and without
waiver or breach of any material provision thereof or if all of the
representations, warranties, statements and assumptions upon which we relied are
not true and accurate at all relevant times.  In the event any one of the
statements, representations, warranties or assumptions upon which we have relied
to issue this opinion is incorrect, our opinion might be adversely affected and
may not be relied upon.

     4.  This opinion is intended solely for the benefit of you and your
stockholders; it may not be relied upon by any other person or entity, and may
not be made available to any other person or entity without our prior written
consent.  We hereby consent, however, to the use of this opinion as an exhibit
to the Registration Statement and further consent to the use of our name
whenever appearing in the Registration Statement, including the Prospectus/Proxy
Statement constituting a part thereof, and any amendments thereto.



                                 Very truly yours,



                                 ROPES & GRAY