准同步数字系列

  • 网络pdh;Plesiochronous digital hierarchy;PDH Plesiochronous digital hierarchy
准同步数字系列准同步数字系列
  1. 电信传输方式自模拟转变为数字以来,一直沿用的是PDH(PlesiochronousDigitalHierarchy,准同步数字系列)传输方式。

    After telecom communicaton 's style changed from analog to digital , the communication mode had been PDH ( Plesiochronous Digital Hierarchy ) .

  2. SDH具有全世界统一的网络节点接口,标准化的信息等级结构,能够兼容现有的PDH准同步数字系列传输系统,使得全世界传输系统能够在STM-N级别上进行互联互通。

    SDH has the unified network node interface ( NNI ), standardized information class structure in all the world and can be compatible with PDH , which makes all the transmission network systems can communicate with each other on the level of STM-N.