YD/T 2008-1993.Standard for design of Telecommunications facilites in civic residential district and...
YD通讯标准
YD通讯标准
YD通讯标准
YD/T 2008-2009 基于统一 IMS 的业务技术要求多媒体彩铃业务(第一阶段)
YD/T 2008-2009.Technical requirement for services based on the unified IMS customized multimedia ale...