随着光网络和光节点技术的不断发展，出现了以自动交换光网络(ASON)为代表的下一代光网络。它通过引入控制平面并结合GMPLS(通用多协议标签交换)协议实现连接的自动建立和拆除，并在相应机制下完成网络故障的动态保护和恢复，动态调配网络资源，可以更好的满足用户和运营商的需要。路由技术是实现ASON的关键技术，由于采用了全新的网络体系，ASON网络的路由计算由基于GMPLS的约束路由算法模块完成，基于约束的路由算法既要在源．目的节点之间找到一条最短路径，还要保证该路径满足流量工程需求，可以说约束路由技术是ASON的关键技术。 本文首先介绍了ASON的概念及其发展状况，接着介绍了ASON体系结构及其路由特点，引出ASON的路由问题；随后介绍了GMPLS控制协议和基于GMPLS的约束路由技术；在此基础上，引出了共享风险链路组(SRLG)的概念，分析了基于SRLG条件约束的KSP算法的缺陷，提出了改进算法。该算法将SRLG信息引入链路权值，既考虑了KSP算法涉及的Qos约束，如带宽、延迟等，还通过负载因子实现了避免陷阱和流量均衡。一方面可以查找多条SPLG分离路径，然后根据网络保护/恢复机制为业务建立工作路径和备份路径，另一方面将带宽剩余较多的链路作为业务通路，避免过多业务拥挤在少数最短路径上。在GLASS仿真平台上的仿真结果表明，该算法是可行有效的，能够降低网络业务阻塞率，提高网络资源利用率。

With the increasing development of op6cal network and o叩cal node techonolgy,next generation op6cal network appeared which is represented by Automatic Switch Optical Network(ASON)．Through the introduction ofcontrol plane under the cooperation ofG～衅LS protocols，It can s既l】p andtake down a connection automatically,complete the protection and recovery ofnetwork failures with Sortie rules,allocate network∞尉x哪嗽dynamically,and then meet the needs ofusers andoperators b融tef．Routing tochonolngy is the key tO realize ASON, $inO∞use anew network hierarchy,ASON completes the network muting compufion through the constraint routing algofithm modules with GMPLS protocols．W蚴e looking for a shortest path betweu·Ii a瓢)l撇node and a destination node．constraint routing algorithm must guarantee the仃a伍c engineering request．It伽be said that the constraint rouling techonology is the ke：y part for ASON． This thesis firstly intlDduces the concept and the develpment of ASON．then introduce the hierarchy ofASON and its muting techonology characteristics，which draw out the routing problem of ASON．After也a1．it in佃oduces the G～口LS conl田ol protocols and the constraint routing tcchonology with G～口LS；Then it draws out the concept of Shared IHsk Link Oroup(SRLO)and analyses the problem of KSP algorithm based on伽咀straim SRLQ an improved algorithm is put fonvard which take SRLG as a part of link cost,the algorithm considers Some Qos parameters involved in KSP algorithm like bandwidth,delay,ctc．Further, it considers a load-balanced factor that makes the algorithm c,an find mole disjoint paths for work path and backup path with network Protection／Restoration system and also can find the links with more free bandwidth to u∞to avoid congestion in some shortest paths．，11坞 simulation lx!sults on GLASS platform validate the algorithm to be available and ri龇it can reduce the congestion ofnetwork and improve the lIIility ofnetwork resources．