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                                                                    EXHIBIT 10.3

                       ASSIGNMENT AND ASSUMPTION AGREEMENT

            This Assignment and Assumption Agreement, dated December 15, 2004
(this "Agreement"), is entered into by and among UBS AG, a Swiss banking
corporation (the "Swap Counterparty"), Corporate Asset Backed Corporation, a
Delaware corporation (the "Assignor"), and CABCO Series 2004-102 Trust (SBC
Communications Inc.), a trust created under the laws of the State of New York
(the "Assignee").

                                    RECITALS

            WHEREAS, the Assignor entered into an ISDA Master Agreement
(including the schedule thereto) and a confirmation (the "Confirmation")
thereunder, with the Swap Counterparty, dated as of December 7, 2004, whereby
the Confirmation provided for, among other things, the Assignor to exchange
interest payments received by the Assignor in respect of the Underlying
Securities for the Floating Amounts from the Swap Counterparty;

            WHEREAS, the Assignee entered into an ISDA Master Agreement
(including the schedule thereto) with the Swap Counterparty, dated as of the
date hereof;

            WHEREAS, the Assignor desires to assign, transfer, and convey its
rights and obligations (excluding the one-time payment paid by the Swap
Counterparty to the Assignor) under the Confirmation to the Assignee in
accordance with the terms hereof; and

            WHEREAS, the Assignee desires to acquire such rights and obligations
from the Assignor in accordance with the terms hereof.

            NOW, THEREFORE, the undersigned, in consideration of the premises,
covenants and agreements contained herein, do hereby agree as follows:

            1. Definitions. Capitalized terms used but not defined herein shall
have the respective meanings ascribed to such terms in the Confirmation.

            2. Assignment. Upon the execution of this Agreement by the parties
hereto, the Assignor hereby assigns, transfers, and conveys all of the
Assignor's rights) and obligations (excluding the one-time payment paid by the
Swap Counterparty to the Assignor) under the Confirmation to the Assignee. Such
transfer, conveyance, and assignment shall be effective as of the date hereof.

            3. Assumption. Upon the execution of this Agreement by the parties
hereto, the Assignee hereby absolutely and irrevocably accepts the foregoing
assignment and hereby assumes to be solely liable and responsible for, and
covenants to be solely liable and responsible for, any liability with respect to
the rights and obligations assigned to the Assignee pursuant to Section 2
hereof, arising on or after the date hereof, all

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subject to the terms and conditions of the Confirmation. Such acceptance,
assumption, and covenant shall be effective as of the date hereof.

            4. Future Cooperation. Each of the parties hereto agrees to
cooperate at all times from and after the date hereof with respect to all of the
matters described herein, and to execute such further assignments, agreements,
releases, assumptions, amendments, notifications and other documents as may be
reasonably requested for the purpose of giving effect to, or evidencing or
giving notice of, the transactions contemplated by this Agreement.

            5. Binding Effect. This Agreement shall be binding upon, and shall
inure to the benefit of, the parties hereto and their respective successors.

            6. Third Party Beneficiary. This Agreement is entered into only for
the benefit of the parties and their respective successors, and nothing
hereunder shall be deemed to constitute any person a third party beneficiary to
this Agreement.

            7. Further Assignment. No party may assign its interest in this
Agreement without the prior written consent of the other party.

            8. Execution in Counterparts. This Agreement may be executed in
counterparts, each of which shall be deemed an original, but all of which shall
constitute one and the same instrument.

            9. Severability. In case any provision in this Agreement shall be
declared or held invalid, illegal, or unenforceable, in whole or in part,
whether generally or in any particular jurisdiction, such provision shall be
deemed amended to the extent, but only to the extent, necessary to cure such
invalidity, illegality, or unenforceability, and the validity, legality, and
enforceability of the remaining provisions, both generally and in every other
jurisdiction, shall not in any way be affected or impaired thereby.

            10. Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK. ANY LEGAL SUIT,
ACTION OR PROCEEDING AGAINST ANY PARTY ARISING OUT OF OR RELATING TO THIS
AGREEMENT SHALL BE INSTITUTED IN ANY FEDERAL OR STATE COURT IN THE BOROUGH OF
MANHATTAN, CITY OF NEW YORK. EACH PARTY HEREBY (A) IRREVOCABLY WAIVES, TO THE
FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY OBJECTION WHICH IT MAY NOW OR
HEREAFTER HAVE TO THE LAYING OF VENUE OF ANY SUCH SUIT, ACTION OR PROCEEDING
BROUGHT IN SUCH A COURT AND ANY CLAIM THAT ANY SUCH PROCEEDING BROUGHT IN SUCH A
COURT HAS BEEN BROUGHT IN AN INCONVENIENT FORUM, AND (B) IRREVOCABLY SUBMITS TO
THE JURISDICTION OF ANY SUCH COURT IN ANY SUCH SUIT, ACTION OR PROCEEDING.

                                        2

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

                                           UBS AG

                                           By: /s/ James B. Fuqua
                                               ---------------------------------
                                               Name: James B. Fuqua
                                               Title: Director and Counsel
                                                      Region Americas Legal
                                                      Fixed Income Section

                                           By: /s/ Marie-Anne Clarke
                                               ---------------------------------
                                               Name: Marie-Anne Clarke
                                               Title: Director and Counsel
                                                      Region Americas Legal
                                                      Fixed Income Section

                                              CORPORATE ASSET BACKED CORPORATION

                                           By: /s/ Robert D. Vascellaro
                                               ---------------------------------
                                               Name: Robert D. Vascellaro
                                               Title: Vice President

                                           By: /s/ James Hausmann
                                               ---------------------------------
                                               Name: James Hausmann
                                               Title: Vice President

                                           CABCO SERIES 2004-102 TRUST
                                           (SBC COMMUNICATIONS INC.)

                                           By: U.S. Bank Trust National
                                               Association, not in its
                                               individual capacity but solely as
                                               Trustee

                                           By: /s/ David J. Kolibachuk
                                               ---------------------------------
                                               Name: David J. Kolibachuk
                                               Title:   Vice President