交换机中同步以太网技术的研究及其实现

[摘要] 提出了一种支持同步以太网交换机工作在主从模式状态下同步时钟网络架构，及其在不同工作模式下的时钟同步机制；提出了交换机工作在从模式状态系统同步链路时钟的优先级选择策略，以及工作在主模式状态下交换机系统时钟指定选择原则。实践表明，这种同步以太网时钟架构和同步机制能很好地满足网络应用。

[关键词] 同步以太网；以太网同步状态消息；锁相环；漂移

[Abstract] In this paper, we propose a synchronous clock network architecture for the Ethernet switch (ES) so that synchronous Ethernet (Sync-E) is achieved when the ES is in slave or master mode. We also propose different synchronous clock mechanisms for the ES in different modes. We introduce the priority selection strategy of synchronous clock link when the ES is in slave mode. The specific selection principle for the system clock when the ES is working in the master mode is also introduced. Finally, we suggest that this synchronous Ethernet clock architecture and mechanisms can meet needs of network applications.

[Keywords] synchronous Ethernet; Ethernet synchronization messaging channel; phase locked loop(PLL); wander