信息等级 meaning in English

message class

Sdh possesses the unified network node interface ( nni ) and standardized information class structure in the world . sdh can be compatible with pdh . it makes all the transmission network systems can communicate with each other on the level of stm - n
Sdh具有全球统一的网络节点接口,标准化的信息等级结构,能够兼容pdh准同步数字系列,使得全世界传输系统能够在stm - n级别上实现互联互通。