8032v2和v1,v3对照学习笔记_v2篇.docx

G.8032/Y.1344 2010/03 Summary APS protection switching mechanisms(characteristics, architectures) ETH layer Ethernet ring topologies incorporates Amendment 1 (2010), Appendix X (minimizing segmentation in interconnected rings) multiple faults that could cause segmentation in a network of interconnected rings. uses additional management information and configuration of MEP Appendix XI (end-to-end service resilience) ring protection to interact with the full service protection ITU-T G.8031/Y.1342 1 Scope APS Protection switching mechanisms for ETH layer Ethernet Ring topologies The ETH layer ring maps to the physical layer ring structure. 2 References [ITU-T G.805] [ITU-T G.806] 2009版 [ITU-T G.808.1] [ITU-T G.809] [ITU-T G.870] [ITU-T G.8010] [ITU-T G.8021] [ITU-T Y.1731] [IEEE 802.1Q] 3 Definitions 3.1 Terms defined elsewhere 和1相比，唯一的区别是G.8021中多定义了一个ETHDi/ETH adaptation function (ETHDi/ETH_A) 3.2 Terms defined in this Recommendation 3.2.1 Ethernet ring 由ring node形成的一个物理上闭合的回路，每个ring node和邻接的ring node相连。注意表述中说的是ethernet ring和ethernet ring node, 并非erp ring或erp ring node,即讨论物理层，Ethernet层面，环的组成和连接，erp ring 和node 映射到该ring物理结构上，实际情况Ethernet ring 简写不就是ERP吗？想多了 中，如果其中有非支持erp的ring node，应视为透明的link；由此产生的单通状态【如cc单通，或一侧link单通】按erp单通逻辑处理假如中间节点不支持ERP，则中间节点不会控制端口的block或unblock,此时有无cc，以及cc有否defect都没有关系；两侧节点会care cc状态和link状态 。 3.2.2 Ethernet ring node A network element which implements at least the following functionalities: ETH_C+ ETH_FF for forwarding APS Two ring ports, including ETHDi/ETH adaptation function ERP control process controlling the blocking and unblocking of traffic over the ring ports. 上述几个function在G.8021中定义，需要进一步学习 3.2.3 ERP instance 3.2.4 interconnection node 表述相当拗口，逻辑还是简单的，简单说互联节点，就是连接多个ring的节点；多个ring中，一个是major ring, 每个互联节点有2个ring port参与， 其它都是sub-ring，每个互联节点有且只有一个ring port参与. Be common to 与…共有 互联节点和共享节点不同，共享节点是多个ring共享该节点，各个ring彼此独立，每个ring，有2个ring port参与 在没有定义major ring和sub ring的时候抛出interconnection node的概念,又没有图说明，是不妥当滴。 3.2.5 major