ETSI EN 302 646-4 English Printed Edition English PDF Integrated Services Digital Network (ISDN); Signalling System No.7 (SS7); Digital cellular telecommunications system (Phase 2+); Application of ISDN User Part (ISUP) version 3 for the ISDN-Public Land Mobile Network (PLMN) signalling interface; Part 4: Abstract Test Suite (ATS) and Protocol Implemen

standard published 11/01/2000 by European Telecommunications Standards Institute