DIN EN 301001-2:1999
综合业务数字网(ISDN).呼出携带补充服务.数字用户用1号信令系统协议.第2部分:协议执行一致性声明(PICS).形式规范
Integrated Services Digital Network (ISDN) - Outgoing Call Barring (OCB) supplementary services; Digital Subscriber Signalling System No. one (DSS1) protocol - Part 2: Protocol Implementation Conformance Statement (PICS) proforma specification [Endorsemen