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                                                                  Exhibit 10.8.2


                       ASSIGNMENT AND ASSUMPTION OF LEASE


      THIS AGREEMENT, made as of the 18th day of November, 1996, by and between
PENRIL DATACOMM NETWORKS, INC., a Delaware corporation ("Assignor"), and ACCESS
BEYOND, INC., a Delaware corporation ("Assignee").


                              W I T N E S S E T H:

      WHEREAS, pursuant to a certain lease dated March 31, 1989, entered into
between REAL ESTATE INCOME PARTNERS III, LIMITED PARTNERSHIP, a Delaware limited
partnership, as landlord ("Landlord"), and Assignor (formerly known as Penril
Corp.), as tenant, as amended by a certain Letter Agreement dated may 14, 1990
and by a certain Amendment to Lease dated as of November 15, 1996, (as amended,
collectively, the "Lease"), a copy of which Lease is attached hereto as Exhibit
"A" and which by reference is made a part hereof, Assignor has leased
approximately 54,874 square feet of office space in the building commonly known
for address purposes as 1300 Quince Orchard Boulevard, Gaithersburg, Montgomery
County, Maryland (the "Premises") for a one hundred nineteen (119) month term
commencing November 1, 1989 and ending September 30, 1999; and

      WHEREAS, subject to the written consent of Landlord, Assignee desires to
assume all of Assignor's rights and obligations under the Lease and Assignor
desires to assign to Assignee all of its rights and obligations under the Lease.

      NOW THEREFORE, in consideration of the premises and the mutual covenants
herein contained, the parties hereto hereby agree as follows:

      1. Assignor hereby assigns, sets over and transfers unto Assignee to have
and to hold from and after the date hereof all of the right, title and interest
of Assignor in, to and under the Lease, including, without limitation, all of
the right, title and interest of Assignor in and to any security deposits,
prepaid rent or other sums paid by Assignor as the tenant under the Lease, and
Assignee hereby accepts the within assignment and assumes and agrees with
Assignor to perform and comply with and to be bound by, from and after the date
hereof, all the terms, covenants, agreements, provisions and conditions of the
Lease on the part of the tenant thereunder to be performed, in the same manner
and with the same force and effect as if Assignee had originally executed the
Lease as tenant.

      2. Assignor hereby unconditionally, absolutely and irrevocably agrees to
indemnify and hold Assignee harmless of, from and against any and all costs,
claims, obligations, damages, penalties, causes of action, losses, injuries,
liabilities and expenses, including, without limitation, reasonable attorneys'
fees, arising or accruing under the Lease before the date hereof.
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      3. Assignee hereby unconditionally, absolutely and irrevocably agrees to
indemnify and hold Assignor harmless of, from and against any and all costs,
claims, obligations, damages, penalties, causes of action, losses, injuries,
liabilities and expenses, including, without limitation, reasonable attorneys'
fees, arising or accruing under the Lease on and after the date hereof.

      4. This Agreement shall be binding upon and inure to the benefit of the
parties hereto and their respective successors and assigns, shall not be
modified except by agreement in writing executed by all parties hereto and shall
be governed by the laws of the State in which the property subject to the Lease
is located as such laws are applicable to agreements made and to be performed
entirely within said State.

      IN WITNESS WHEREOF, the parties hereto have duly executed this Agreement
as of the date first above written.

                                    PENRIL DATACOMM NETWORKS, INC.

                                    By: s/Barry E. Beswick
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                                    ACCESS BEYOND, INC.

                                    By: s/Ronald A. Howard
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