Home / Standards / GB/T 21647-2008 GB/T 21647-2008 Active B-ISDN ATM Adaptation Layer Specification : Type 2 AAL B-ISDN ATM 适配层(AAL)类型2技术规范 Standard Type GBT ICS 33.180.20 CCS M33 Status 现行 Issue Date 2008-04-11 Implementation 2008-11-01 Responsible Dept 工业和信息化部(通信) Drafting Unit N/A