Integrated Services Digital Network (ISDN). Signalling System No.7 (SS7). ISDN User Part (ISUP) version 4 for the international interface. Part 21: Anonymous Call Rejection (ACR) supplementary service [ITU- T Recommendation Q.731, clause 4 (1993)]
STANDARD published on 1.5.2002
Designation standards: STN EN 300356-21-V4.2.1
Classification mark: 870356
Catalog number: 20063
Publication date standards: 1.5.2002
Approximate weight : 300 g (0.66 lbs)
Country: Slovak technical standard
Category: Technical standards STN