Packet processing access unit(PPAU)serves as the MAC aggregation function of the DQDB protocal. The main function of PPAU is to process the inconsecutive, asynchronous data on the DQDB network.

• 分组处理访问单元PPAU属于DQDB协议MAC汇聚功能，主要处理DQDB网上非连续性的异步数据。