This amendment to Recommendation Q.2957.1 has been prepared to enable the transfer of additional information that is usable for the control of the operation of the Internet Protocol over switched VC connections. Recommendation Q.2957.1 defines the operation of the Digital subscriber Signalling System No. 2 (DSS2) for the support of the User-to-User Signalling (UUS) supplementary service at the TB or the coincident SB and TB reference point of the user to network interface of the Broadband Integrated Services Digital Network (B-ISDN).