scope:

Scope, Purpose and Application

ANSI T1.110-1999 was originally based on the 1988 Blue Book specification of Signalling System No. 7 (SS#7) for international use issued by the CCITT Study Group XI (Vol. VI Fascicles VI.7 and VI.8) and is intended to be generally compatible with that standard and its successors. It has been appropriately modified for use within and between U.S. networks to meet the anticipated needs and applications of those entities. In general, these modifications fall into two categories:

(1) The specification of options designated by the ITU-T (formerly CCITT) for national use;

(2) Extensions to the 1992 protocol to provide for new applications of the SS7 protocol.

This is in accordance with current and projected ITU-T activity.

The objectives of the implementation of SS7 in U.S. networks go beyond basic circuit switched call control signalling, and place major emphasis on the support of advanced capabilities such as signalling for Integrated Services Digital Networks (ISDN), support of an Operations Administration and Maintenance (OA&M) application, support of Transaction Capabilities, and others yet to be defined. National versions of the 1988 Blue Book and later versions of the Telephone User Part (TUP) and Data User Part (DUP)¹ will not be included in this document and will not be supported in U.S. networks. Instead, information describing additional protocol capabilities and new applications is provided. Further information on new applications will be included as detailed definition work proceeds.

¹⁾ Not specified for U.S. Networks