Summary

This Recommendation provides guidance, principles and requirements for addressing reference points located at subscribers' premises, servers allowing communications between terminals, applications and persons in B-ISDN networks.

This revision of E.191 was required in order to reflect the fact that B-ISDN addressing has also incorporated the use of non-E.164 ATM End System Addresses (AESAs) to be recognized in ATM Service Providers (ASP) networks.

This Recommendation proposes that ASPs use the ITU-IND AESA as the preferred method of B‑ISDN addressing. Native E.164 and E.164 AESAs will continue to be supported. It is also recognized that other AESA formats are assigned and in use by ASPs.