1. MSPP SRQ1.0
   1. Brief Functional Requirement
      1. 监视链路状态
      2. 监视以太网虚连接&光纤连接问题和配置问题
      3. 配合NMS工作
      4. 支持告警抑制
      5. 用户分级 operators, providers, customers
   2. Functional Model
      1. CFM frames distinguished from ordinary data frames only by destination MAC(0180c2000030) address and E-Type(0x8902)
      2. Continuity Check Protocol
      3. Loopback Protocol
         1. Loopback Messages (LBM)
         2. Loopback Reply Message (LBR)
      4. Link Trace Protocol
         1. MEPs send multicast Link Trace Message (LTM) on a particular MEG to identify adjacency relationships with remote MEPs and MIPs at the same administrative level.
         2. The message body of an LTM includes a destination MAC address of a target MEP that terminates the link trace.
   3. General Requirements
      1. 支持VPLS、HA safe
      2. 8个Maintenance Domain，with multiple non-overlapping MDs at each MD Level？
      3. 逻辑接口支持创建单一MIP，R06
      4. 每个端口的每个 vlan 支持8个Up or Down MEP， 每个MEP在不同的MD Leavel. R09
      5. auto-discovery of remote MEPs
      6. R14 MUST support for un-learning the existence of a remote MEP that has been auto-discovered by a clear command.
      7. MAY support the ability to administratively disable a MEP as defined in Section 20.9.1 of IEEE P802.1ag/D8
      8. MUST support MP (MEP and MIP) for cross-card multi-link Ethernet (LAG)
      9. 子主题 10
      10. 子主题 11
      11. 子主题 12
      12. 子主题 13
      13. 子主题 14
   4. Entity
      1. MD被分配一个唯一的Level号，MD可以包含不能交叉，外部的level要比内部的大。
      2. MA：v12还不支持在一个MA里面配置多个MEP
      3. Maintenance Entity (ME) - an entity that requires management.
         1. A ME represents a relationship between two MEPs.
      4. MEP
         1. A MEP is associated with exactly one MA
         2. 终端端口
         3. actions
            1. Periodically transmits Continuity Check Messages (CCMs) & Validates received CFM PDUs
            2. Discards those CFM PDUs at a lower MD Level to that configured in the MEP
            3. Transmits Loopback Messages (LBMs) and receives Loopback Replies (LBRs)
            4. Transmits Linktrace Messages (LTMs), and transmits and receives Linktrace Replies (LTRs)
            5. Responds to LBMs with LBRs & Responds to LTMs with LTRs
            6. Maintains the MEP CCM Database
            7. May maintain the MIP CCM Database
            8. Maintains the variables in 20.9 of 802.1ag
         4. drops all CFM frames of its level or lower that come from the wire side
      5. MIP
         1. Maintenance Entity Group Intermediate Point (MIP)
            1. A MIP does not initiate OAM frames and takes no action on the transit ETH flows
            2. Validates received LTMs
            3. Optionally, validates received CCMs, and builds the MIP CCM Database
            4. Responds to LBMs with LBRs
            5. Responds to LTMs by forwarding them and responding with LTRs
         2. MIP forwards CCM frames generated by MEPs
         3. All CFM frames at a lower level are stopped and dropped.MIPs are Passive points, respond only when triggered by CFM trace route and loop-back messages
         4. Maintenance Intermediate Points 内部端口
      6. Maintenance Point (MP) is one of either MEP or MIP
2. Test
   1. IXIA test plan
      1. 一致性测试：是否符合 IEEE 802.1ag-2007
      2. CCM间隔测试：不同CCM发送间隔时间的测试
      3. MIP可扩展性：验证Linktrace的TTL能力
      4. MEP/RMEP可扩展性：验证一个MA里面多个所有MEPs/RMEPs的处理能力
      5. Error/Defect条件检测和处理
      6. CFM网络中流量的转发能力
      7. CFM协议多状态检查和流量混合测试：复杂环境下CFM状态转换和实现能力
      8. 多MD等级测试
3. Frame analysis
   1. LBR-loopback reply: 单播 协议号8902+0002
   2. LTR-Linktrace Reply: 单播 协议号8902+0004
   3. CCM-Continutiy Check Message: 组播 目的MAC=0180C2000030，最后一位等于MD level
   4. LTM-Linktrace Message：组播目的mac=0180c200003x(0xMDlevel+8),协议号89020005
   5. LBM-Loopback Message：单播，协议号89020003
   6. 子主题 8
   7. 子主题 9
4. 分支主题 4
   1. Dest-addr: 目的MAC地址为蛮熟协议组播地址0x0180c200~02. 慢速协议报文的特点就是不能被网桥转发，因此无论是否具备OAM功能或者OAM功能是否激活，EFM OAM报文都不能跨多跳转发。
   2. Source-addr: 发送端口的MAC地址，没有则采用桥MAC.
   3. 子主题 3
   4. 子主题 4
   5. 子主题 5