HFC网络MAC协议及碰撞解决

MAC Protocols and Collision Resolution in HFC Networks

ＨＦＣ网络（混合光纤同轴网）采用树状拓扑结构，分布于较广的区域，有较大的延时，这使得ＨＦＣ网络中的ＭＡＣ（介质访问控制）协议的设计成为一个值得研究的问题。本文对ＨＦＣ网络中几种有影响的ＭＡＣ协议进行了综述，重点介绍了ＩＥＥＥ８０２．１４工作组的８０２．１４ 草案３。ＨＦＣ网络介质访问控制协议中最有特色的是碰撞解决算法，８０２．１４ 协议采用ｐ 坚持算法结合ｎ 叉树算法，前者用于预先避免碰撞，而后者用于解决已发生的碰撞。

Due to the HFC network's tree topology,large service area and great round trip delay,it is an issue worth researching when we design the MAC (Media Access Control) protocol in HFC networks. This paper summarizes several MAC protocols in HFC network, and especially introduces Draft 3 of IEEE 802.14. The most representative feature of MAC protocols in the HFC network is its collision resolution algorithm. IEEE 802.14 MAC protocol uses p persistence algorithm as well as n ary tree. The former is used to avoid collision in advance,while the latter is used to resolve the collisions that have occurred.