ABSTRACT: This document replaces TA-NWT-001509.

This Generic Requirements (GR) document, GR-1509, Generic Requirements for Call-by-Call Service Selection Access to Interexchange Carrier (IXC) Services Using Signaling System No. 7 (SS7), provides the Telcordia view of generic switching and signaling requirements for access to services provided by an Interexchange Carrier (IXC) on a per-call basis using the SS7 protocol. This access is intended for use by Class II Equipment, Basic Business Groups (BBGs), and Integrated Services Digital Network Basic Business Groups (BBG-Is). Call-by-call access IXC services enables a caller to request that the IXC apply a particular service to a given call request that is routed over an SS7 connection serving the IXC. Call-by-call service selection access to IXC services eliminates the need for dedicated facilities between the serving Local Exchange Carrier (LEC) and IXC for individual services.

Revision 1 to GR-1509 includes changes to the GR to incorporate the resolution for the handling of non-E.164 called numbers in SS7, alignment of the SS7 NSF parameter with T1S1 standards (including correcting the codepoint value for the parameter), and screening of the called number.

This GR also includes one or more Issue List Reports (ILRs) that details open or closed technical issues in the main document. The ILR(s) are automatically sent free of charge to the GR document purchaser.