ETSI TS 102 024-2-2003 网络上电信和互联网协议的协调(TIPHON)(第4次发布).TIPHON系统中的端到端业务质量.第2部分:业务语音质量定义(QoS)级别(版本4.1.1)
Telecommunications and Internet Protocol Harmonization Over Networks (TIPHON) Release 4; End-to-end Quality of Service in TIPHON Systems; Part 2: Definition of Speech Quality of Service (QoS) Classes