Exhibit 5.1



May 31, 1996




Board of Directors
Penril DataComm Networks, Inc.
1300 Quince Orchard Boulevard
Gaithersburg, Maryland  20878

Gentlemen:

    Penril DataComm Networks, Inc., a Delaware corporation (the
"Company"), intends to file with the Securities and Exchange
Commission under the Securities Act of 1933, as amended, a
Registration Statement on Form S-8 (the "Registration Statement")
with respect to 1,000,000 shares (the "Shares") of the Company's
common stock, $.01 par value per share (the "Common Stock"), to
be issued from time to time pursuant to the 1995 Long-Term
Incentive Plan of Penril DataComm Networks, Inc. (the "Incentive
Plan").  Capitalized terms not defined in this letter have the
meanings given to them in the Incentive Plan.

    You have requested our opinion in connection with the
Company's filing of the Registration Statement.  In this
connection, we have examined and relied upon originals or copies,
certified or otherwise identified to our satisfaction as being
true copies, of all such records of the Company, all such
agreements, certificates of officers of the Company and others,
and such other documents, certificates and corporate or other
records as we have deemed necessary as a basis for the opinions
expressed in this letter, including, without limitation, the
Company's Amended and Restated Certificate of Incorporation, as
amended, and the Registration Statement.

    In our examination, we have assumed the genuineness of all
signatures, the legal capacity of all natural persons, the
authenticity of all documents submitted to us as originals and
the conformity to authentic original documents of all documents
submitted to us as certified or photostatic copies.

    We have investigated such questions of law for the purpose
of rendering the opinions in this letter as we have deemed
necessary.  We express no opinion in this letter concerning any
law other than the General Corporation Law of the State of
Delaware.

    This opinion is being rendered to you as of today.  The
opinion expressed herein assumes that there is no change in the
facts and circumstances and law in effect on the date of this
opinion, particularly, as they relate to corporate authority and
the Company's good standing under Delaware law.  We have assumed
the Company will remain in good standing as a Delaware
corporation at all times when shares of Common Stock are sold
pursuant to the Incentive Plan.

    On the basis of and in reliance on the foregoing, we are of
the opinion that the Shares of the Common Stock to be issued
pursuant to the Incentive Plan, when and if issued in accordance
with the terms of the Incentive Plan, will be legally issued,
fully paid and nonassessable.  

    The opinion in this letter is rendered only to the Company
in connection with the filing of the Registration Statement.  We
consent to the filing of this letter as an exhibit to the
Registration Statement.  The opinion may not be relied upon by
the Company for any other purpose.  This letter may not be
paraphrased, quoted or summarized, nor may it be duplicated or
reproduced in part.

                                  Very truly yours,



                                  BENESCH, FRIEDLANDER,
                                  COPLAN & ARONOFF P.L.L.