ITU-T E.500-1998
话务密度测量原理 E系列:全面网络操作,电话服务,服务操作和人为因素 服务质量,网络管理和通信工程
Traffic Intensity Measurement Principles - Series E: Overall Network Operation Telephone Service Service Operation and Human Factors Quality of Service Network Management and Traffic Engineering - Traffic Engineering - Measurement and Recording of Traffic