ÖNORM EN 300485 V 1.3.1:2001-07
Действует
Integrated Services Digital Network (ISDN) - Definition and usage of cause and location in Digital Subscriber Signalling System No. one (DSS1) and Signalling System No.7 (SS7) ISDN User Part (ISUP) [ITU-T Recommendation Q.850 (1998) with addendum modified]