EXECUTION COPY


             


            
            ASSIGNMENT AND ASSUMPTION AGREEMENT


             


            
            THIS ASSIGNMENT AND ASSUMPTION AGREEMENT, dated December 28, 2007, is
            entered into by and between Credit Suisse Securities (USA) LLC, a Delaware company
            (“Assignor”), and Credit Suisse First Boston Mortgage Securities Corp., a
            Delaware corporation (“Assignee”).


            
            For and in consideration of the sum of TEN DOLLARS ($10.00) and other
            valuable consideration the receipt and sufficiency of which hereby are acknowledged,
            and of the mutual covenants herein contained, the parties hereto hereby agree as
            follows:


            
            1.           
            The Assignor hereby grants, transfers and assigns to Assignee its the
            right, title and interest of Assignor in, to and under the certificate that represents
            a 36.106319085% beneficial interest in the Class 5-A-1 Certificates issued by the TBW
            Mortgage-Backed Trust Series 2006-2 (the “Underlying
            Certificates”).


            
            2.            
            The Assignor warrants and represents to, and covenants with, the
            Assignee that:


            
            (a)          
            The Assignor is the lawful owner of the Underlying Certificates with the
            full right to transfer the Underlying Certificates free from any and all claims and
            encumbrances whatsoever;


            
            (b)          
            The Assignor has not received notice or, and has no knowledge of, any
            offsets, counterclaims or other defenses with respect to the Underlying
            Certificates;


            
            (c)          
            The Assignor has not waived or agreed to any waiver under, or agreed to
            any amendment or other modification of, the Underlying Certificates. The Assignor has
            no knowledge of, and has not received notice of, any waivers under or amendments or
            other modifications of, or assignments of rights or obligations under or defaults
            under, the Underlying Certificates; and


            
            (d)          
            Neither the Assignor nor anyone acting on its behalf has offered,
            transferred, pledged, sold or otherwise disposed of the Underlying Certificates, any
            interest in the Underlying Certificates or any other similar security to, or solicited
            any offer to buy or accept a transfer, pledge or other disposition of the Underlying
            Certificates, any interest in the Underlying Certificates or any other similar security
            from, or otherwise approached or negotiated with respect to the Underlying
            Certificates, any interest in the Underlying Certificates or any other similar security
            with, any person in any manner, or made by general solicitation by means of general
            advertising or in any other manner, or taken any other action which would constitute a
            distribution of the Underlying Certificates under the Securities Act of 1933 (the
            “1933 Act”) or which would render the disposition of the Underlying
            Certificates a violation of Section 5 of the 1933 Act or require registration pursuant
            thereto.


            
                	
                             

                        	
                             

                        


            


            

            
            


            

            

            
                
                3.              
                The Assignee warrants and represents to, and covenants with, the Assignor
                that:

            


            
            (a)          
            The Assignee is a corporation duly organized, validly existing and in
            good standing under the laws of the jurisdiction of its incorporation, and has all
            requisite corporate power and authority to acquire, own and purchase the Underlying
            Certificates;


            
            (b)          
            The Assignee has full corporate power and authority to execute, deliver
            and perform under this Assignment and Assumption Agreement, and to consummate the
            transactions set forth herein. The execution, delivery and performance of the Assignee
            of this Assignment and Assumption Agreement, and the consummation by it of the
            transactions contemplated hereby, have been duly authorized by all necessary corporate
            action of the Assignee. This Assignment and Assumption Agreement has been duly executed
            and delivered by the Assignee and constitutes the valid and legally binding obligation
            of the Assignee enforceable against the Assignee in accordance with its respective
            terms;


            
            (c)          
            To the best of Assignee’s knowledge, no material consent,
            approval, order or authorization of, or declaration, filing or registration with, any
            governmental entity is required to be obtained or made by the Assignee in connection
            with the execution, delivery or performance by the Assignee of this Assignment and
            Assumption Agreement, or the consummation by it of the transactions contemplated
            hereby;


            
            (d)          
            The Assignee agrees to be bound, as Purchaser, by all of the terms,
            covenants and conditions of the Underlying Certificates, and from and after the date
            hereof, the Assignee assumes for the benefit of the Assignor all of the
            Assignor’s obligations as Purchaser thereunder, with respect to the Underlying
            Certificates;


            
            (e)          
            The purchase price being paid by the Assignee for the Underlying
            Certificates is in excess of $250,000 and will be paid by cash remittance of the full
            purchase price within sixty (60) days of the sale;


            
            (f)           
            The Assignee is acquiring the Underlying Certificates for investment for
            its own account only and not for any other person;


            
            (g)          
            The Assignee considers itself a substantial, sophisticated institutional
            investor having such knowledge and financial and business matters that it is capable of
            evaluating the merits and the risks of investment in the Underlying
            Certificates;


            
            (h)          
            The Assignee has been furnished with all information regarding the
            Underlying Certificates that it has requested from the Assignor;


            
            (i)           
            Neither the Assignee nor anyone acting on its behalf has offered,
            transferred, pledged, sold or otherwise disposed of the Underlying Certificates, an
            interest in the Underlying Certificates or any other similar security to, or solicited
            any offer to buy or accept a transfer, pledge or other disposition of the Underlying
            Certificates, any interest in the Underlying Certificates or any other similar security
            from, or otherwise approached or negotiated with respect to the Underlying
            Certificates, any interest in the Underlying Certificates or any other similar security
            with, any person in any manner, or made any general solicitation by means of general
            advertising or in any other manner, or taken any other action which would constitute
            a


             


            
                	
                            
                             

                        	
                            
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            distribution of the Underlying Certificates under the 1933 Act or which
            would render the disposition of the Underlying Certificates a violation of Section 5 of
            the 1933 Act or require registration pursuant thereto, nor will it act, nor has it
            authorized or will it authorize any person to act, in such manner with respect to the
            Underlying Certificates; and


            
            (j)           
            Either: (1) the Assignee is not an employee benefit plan
            (“Plan”) within the meaning of section 3(3) of the Employee Retirement
            Income Security Act of 1974, as amended (“ERISA”) or a plan (also
            “Plan”) within the meaning of Section 4975(e)(1) of the Internal Revenue
            Code of 1986, as amended (“Code”), and the Assignee is not directly or
            indirectly purchasing the Underlying Certificates on behalf of, investment manager of,
            as named fiduciary of, as trustee of, or with assets of, a Plan; or (2) the
            Assignee’s purchase of the Underlying Certificates will not result in a
            prohibited transaction under section 406 of ERISA or Section 4975 of the
            Code.


             


            
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            IN WITNESS WHEREOF, the parties have caused this Assignment and
            Assumption to be executed by their duly authorized officers as of the date first above
            written.


            
                	
                            
                            Credit Suisse Securities (USA) LLC,


                            
                            as Assignor


                            
                             


                            
                            By:______________________________________
                             


                            
                            Name:


                            
                            Title:

                        	
                            
                            CREDIT SUISSE FIRST BOSTON MORTGAGE SECURITIES
                            CORP.,


                            
                            as Assignee


                            
                            By:______________________________________
                                


                            
                            Name:


                            
                            Title:

                        
	
                            
                             

                        	
                            
                             

                        
	
                            
                            Taxpayer Identification Number:
                            050546650

                        	
                            
                            Taxpayer Identification Number:
                            13-3460894