千兆冗余以太网链路状态检测技术

针对千兆以太网冗余备份网卡的链路切换时间较长，难以满足应用要求的问题，提出一种基于“心跳”帧的新型千兆冗余以太}回链路状态检测方法。通过改进MAC控制器，增加网络状态检测模块用于组织“心跳”帧，并根据检测网络延时对以太网络进行分类，得到Delay网络和No—Delay网络，利用“心跳”帧对冗余链路的实时监控以及MAC控制器对“心跳”帧的统计分析，快速检测出断开链路，缩短链路切换时间。测试结果表明，该硬件检测方法能够迅速检测出断开链路，并在20ms之内完成冗余链路切换，保障网络通信的可靠性和稳定性。

Link Status Detection Technology for Gigabit Redundant Ethernet

To address the issue that the link switch time of gigabit Ethernet redundant Network Interface Card（NIC） is too long and difficult to meet the application requirements, a kind of hardware detection method is proposed. It is a new gigabit redundant Ethernet link status detection method on the basis of ＂heartbeat＂ frame. This method adds the network status detection module used for the organization of ＂heartbeat＂ frame through the improvement of MAC controller, and classifies the Ethernet into two types based on the network latencies： Delay network and No-Delay network. In addition, it can detect the broken link rapidly and shorten the link switch time according to the real：time monitoring to redundant link by ＂heartbeat＂ frame and statistical analyses to ＂heartbeat＂ frame by MAC controller. Test results indicate that this detection method can rapidly detect the disconnected link and the link switch time is in 20 ms, and it can guarantee the reliability and stability of the network communication.