一种基于稳定簇的混合路由协议CBHRP

移动算组网是一种没有有线基础结构支持的移动网络，具有带宽有限和拓扑结构易变的特点。这些特点使得设计一个合适的路由协议具有一定的挑战性。该文针对移动自组网提出了一种基于稳定簇结构、按需路由和预先路由混合、支持单播和组播通信的路由协议CBHRP。CBHRP具有路由控制开销小、主机移动对拓扑结构改变的影响小、通信的初始延迟低和应用范围广的特点。

A Stable Cluster Based Hybrid Routing Protocol for Ad Hoc Mobile Networks

Ad hoc mobile wireless network is an infrastructureless network without fixed routers or central administrator. In this paper, we propose a stable cluster based hybrid ad hoc routing protocol (CBHRP) for ad hoc mobile networks. CBHRP protocol composes of cluster formation, unicast routing and multicast routing.In cluster formation, CBHRP divides the nodes of network into a number of adjacent 2-hop-diameter clusters. CBHRP selects the most stable node in each cluster as the cluster head. Each head maintains information of cluster membership and route. CBHRP uses hybrid routing scheme (proactive and reactive) in unicast routing. In CBHRP a routing zone is defined for each cluster head, and includes the nodes whose minimum distance is 2 cluster from this node. The route of intra-routing zone is proactive. Each cluster head exchanges hello packets periodically with neighbors to update routes.The route of inter-routing zone is reactive. When the source head has no route to destination, the source head sends route request to zone border heads. The border head sends route reply to the source head if it has route to destination, or else it sends request to its zone border heads. CBHRP supports not only unicast, but also multicast.It uses the shared tree without rendezvous point (RP) scheme to multicast.Each cluster head in the tree records its parent head and child heads of the group, from which the head forwards packets and maintains the tree. When a node wants to join a group, its cluster head broadcasts route request to all neighbors. The forwarding nodes in the tree send route reply containing adding path to the request head. Then request cluster head selects the shortest path to be added to the group.In this paper, we prove the correction of CBHRP and compare CBHRP with ZRP, CBRP and AODV. We evaluate the performance of CBHRP in our simulation.CBHRP exhibits the following properties: it decreases control overhead and stabilizes network topology by clustering nodes into group and selecting stable nodes as cluster heads, and it reduces initial communication delay by hybrid proactive and reactive routing mode. Furthermore, the protocol supports multicast and suitable for extensive applications.