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                                                                  Exhibit 10.48



                               AMENDMENT NO. 3 TO
                          LOAN AND SECURITY AGREEMENT

         THIS AMENDMENT NO. 3 TO LOAN AND SECURITY AGREEMENT ("Amendment") is
dated as of July 15, 1999 and is entered into by and between Bank of America
National Trust and Savings Association ("Lender") and Paradyne Corporation
("Borrower"). All capitalized terms used herein but not otherwise defined shall
have the meanings ascribed to them in the Agreement (as hereinafter defined).

                                   WITNESSETH

         WHEREAS, the Borrower and the Lender have entered into that certain
Loan and Security Agreement dated as of July 31, 1996, as amended and
supplemented (the "Agreement"); and

         WHEREAS, the Borrower desires to amend the Agreement and the Lender is
willing to do so, subject to the terms and conditions stated herein;

         NOW, THEREFORE, in consideration of the premises herein contained and
other good and valuable consideration, the receipt and adequacy of which are
hereby acknowledged, the Borrower and Lender hereby agree as follows:

         SECTION 1. Amendment to the Agreement. The Lender and Borrower agree
that the Agreement shall be amended as follows:

                  A.       Amendments to Section 1.1: Definitions. Section 1.1
         of the Agreement is amended by adding the following definitions in the
         appropriate alphabetical order:

                  "'Change of Control' means (a) the direct or indirect
acquisition by any person (as such term is used in Section 13(d) and Section
14(d)(2) of the Exchange Act), or related persons constituting a group (as such
term is used in Rule 13d-5 under the Exchange Act), of:

                  (i)      beneficial ownership of issued and outstanding
         shares of voting stock of the Borrower, the result of which
         acquisition is that such person or such group possesses in excess of
         30% of the combined voting power of all then-issued and outstanding
         voting stock of the Borrower, or

                  (ii)     the power to elect, appoint or cause the election or
         appointment of at least a majority of the members of the Board of
         Directors of the Borrower.

                  provided however, that for purposes of this definition, a
person shall not include (a) Paradyne Networks, Inc. or any affiliate or direct
or indirect subsidiary thereof or (b) any of the General and Limited Partners
of Communications Partners, L.P. or any affiliate of or entity associated with
such General or Limited Partners."

                  "'Exchange Act' means the Securities Exchange Act of 1934,
and regulations promulgated thereunder."


                  B.       Amendment to Section 12. Section 12(o) of the
         Agreement is amended in its entirety to read as

           follows:

                  "(o)     there occurs a Change of Control;"



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                  C.       Amendment to Name of Lender. Effective as of April
         1, 1999, Bank of America National Trust and Savings Association became
         the successor-in-interest to BankAmerica Business Credit, Inc. All
         references in the Agreement and in each Loan Document to "BankAmerica
         Business Credit, Inc." or "BABC" are now amended to refer to "Bank of
         America National Trust and Savings Association" which is the "Lender"
         under the Agreement and the other Loan Documents.

SECTION 2.       Consents. The Lender hereby consents to the following:

                  The non-cash dividend in the amount of approximately $350,000
by the Borrower to Globespan, Inc. which was caused by the sale of certain
equipment by the Borrower to Globespan, Inc.

SECTION 3.Conditions.      The effectiveness of this Amendment is subject to
the satisfaction of the following conditions precedent:

                  A.       Amendment. Fully executed copies of this Amendment
         signed by the Borrower and a ratification signed by the Guarantor
         shall be delivered to Lender.

                  B.       Resolution. A certificate executed by the Secretary
         or Assistant Secretary of Borrower certifying that the Borrower's
         Board of Directors has adopted resolutions authorizing the execution,
         delivery and performance by Borrower of the Amendment shall be
         delivered to Lender.

                  C.       Other Documents. Borrower shall have executed and
         delivered to Lender such other documents and instruments as Lender may
         require.

SECTION 4.        Miscellaneous.

                  A.       Survival of Representations and Warranties. All
         representations and warranties made in the Agreement or any other
         document or documents relating thereto, including, without limitation,
         any Loan Document furnished in connection with this Amendment, shall
         survive the execution and delivery of this Amendment and the other
         Loan Documents, and no investigation by Lender or any closing shall
         affect the representations and warranties or the right of Lender to
         rely thereon.

                  B.       Reference to Agreement. The Agreement, each of the
         Loan Documents, and any and all other agreements, documents or
         instruments now or hereafter executed and delivered pursuant to the
         terms hereof, or pursuant to the terms of the Agreement as amended
         hereby, are hereby amended so that any reference therein to the
         Agreement shall mean a reference to the Agreement as amended hereby.

                  C.       Agreement Remains in Effect. The Agreement and the
         Loan Documents remain in full force and effect and the Borrower
         ratifies and confirms its agreements and covenants contained therein.
         The Borrower hereby confirms that, after giving effect to this
         Amendment, no Event of Default or Default exists as of such date.

                  D.       Severability. Any provision of this Amendment held
         by a court of competent jurisdiction to be invalid or unenforceable
         shall not impair or invalidate the remainder of this




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         Amendment and the effect thereof shall be confined to the provision so
         held to be invalid or unenforceable.

                  E.       APPLICABLE LAW. THIS AMENDMENT AND ALL OTHER LOAN
         DOCUMENTS EXECUTED PURSUANT HERETO SHALL BE DEEMED TO HAVE BEEN MADE
         AND TO BE PERFORMABLE IN THE STATE OF CALIFORNIA AND SHALL BE GOVERNED
         BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF
         CALIFORNIA.

                  F.       Successors and Assigns. This Amendment is binding
         upon and shall inure to the benefit of Lender and Borrower and their
         respective successors and assigns; provided, however, that Borrower
         may not assign or transfer any of its rights or obligations hereunder
         without the prior written consent of Lender.

                  G.       Counterparts. This Amendment may be executed in one
         or more counterparts, each of which when so executed shall be deemed
         to be an original, but all of which when taken together shall
         constitute one and the same instrument.

                  H.       Headings. The headings, captions and arrangements
         used in this Amendment are for convenience only and shall not affect
         the interpretation of this Amendment.

                  I.       NO ORAL AGREEMENTS. THIS AMENDMENT, TOGETHER WITH
         THE OTHER LOAN DOCUMENTS AS WRITTEN, REPRESENTS THE FINAL AGREEMENT
         BETWEEN LENDER AND BORROWER AND MAY NOT BE CONTRADICTED BY EVIDENCE OF
         PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES.
         THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN LENDER AND BORROWER.

         IN WITNESS WHEREOF, the parties have executed this Amendment under
seal on the date first written above.

                                      PARADYNE CORPORATION


                                      By: /s/ James Slattery
                                         --------------------------------------
                                      Name:   James Slattery
                                      Title:  Senior Vice President



                                      BANK OF AMERICA NATIONAL TRUST AND
                                      SAVINGS ASSOCIATION


                                      By: /s/ Gary Whitaker
                                         --------------------------------------
                                      Name:   Gary Whitaker
                                      Title:  Vice President



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                          CONSENTS AND REAFFIRMATIONS

         The undersigned hereby consents to the terms and conditions of that
Amendment No. 3 to Loan and Security Agreement dated as of July 15, 1999,
between Paradyne Corporation and Bank of America National Trust and Savings
Association ("Creditor") and reaffirms its obligations under a Guaranty dated
as of July 31, 1996 (the "Guaranty") made by the undersigned in favor of the
Creditor and acknowledges and agrees that the Guaranty remains in full force
and effect.

         Dated as of July 15, 1999.

                                      PARADYNE CANADA, LTD.



                                      By: /s/ James Slattery
                                         --------------------------------------
                                      Name:   James Slattery
                                      Title:  Senior Vice President




















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                              PARADYNE CORPORATION


                            SECRETARY'S CERTIFICATE


         The undersigned, Secretary of Paradyne Corporation, a corporation
organized under the laws of the state of Delaware, hereby certifies that by
action of the Board or Directors of Paradyne Corporation, the following
resolutions were adopted by unanimous written consent of all of the Directors
of the Company. Said resolutions were adopted as of July 16, 1999 and remain in
full force and effect as of the date of this certificate.

                  NOW, THEREFORE, BE IT RESOLVED, that this Company shall enter
         into an Amendment No. 3 to its Loan and Security Agreement with Bank
         of America National Trust and Savings Association, and

                  RESOLVED FURTHER, that the officers of the Company be, and
         each of them hereby is, authorized and directed to execute and deliver
         on behalf of this Company such amendments and documents and to perform
         such acts and make such filings as may be deemed necessary or
         advisable to implement the foregoing resolution.


         IN WITNESS WHEREOF, I have hereunto set my hand and seal of said
Paradyne Corporation, this 16th day of July 1999.




                                         (ILLEGIBLE SIGNATURE)
                                        ---------------------------------------
(SEAL)                                  Secretary



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