ITU-T E.502-2001
数字电信交换交通测量要求 E系列:全面网络操作 电话服务 服务操作和人员因素 交通工程 交通的测量
Traffic Measurement Requirements for Digital Telecommunication Exchanges Series E: Overall Network Operation Telephone Service Service Operation and Human Factors Traffic Engineering - Measurement and Recording of Traffic Study Group 2