EXHIBIT 10.27

                                    AMENDMENT

       THIS AMENDMENT, dated as of January 10, 2002 and effective as of December
13, 2001 (the "Amendment") is entered into between TOLLGRADE COMMUNICATIONS,
INC. ("Tollgrade") and CHRISTIAN L. ALLISON (the "Executive").

                             AMENDMENT TO AGREEMENT

WHEREAS, Tollgrade and the Executive entered into an Agreement dated as of the
13th day of December, 1995, as amended, governing the employment of Executive
and certain benefits to be received by Executive in the event his employment is
terminated (collectively, the "Agreement"); and

WHEREAS, Tollgrade and the Executive desire to amend the Agreement upon the
terms and conditions stated in this Amendment.

NOW, THEREFORE, in consideration of the promises and the faithful performance of
the mutual covenants herein contained, and intending to be legally bound hereby,
Tollgrade and the Executive agree as follows:

1.     Capitalized terms used herein and not otherwise defined shall have the
       meaning assigned to them in the Agreement.

2.     The Agreement shall be amended to extend the salary terms as currently in
       effect until December 13, 2002.

3.     Except as modified by this Amendment, the provisions of the Agreement
       shall remain in full force and effect.

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


TOLLGRADE COMMUNICATIONS, INC.


By:
    ------------------------               ------------------------------------
Title:                                              Christian L. Allison
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