NetFlow is an embedded feature within Cisco® IOS Software that records network traffic into the device cache to provide extremely granular and accurate traffic measurements. Because network traffic has a flow nature to it, the NetFlow accounting data that is built in the cache, characterizes the IP traffic being forwarded.

导出的NetFlow统计数据可以用于各种目的,包括网络流量计费,usage-based network billing, 网络监控,数据储存。

NetFlow数据记录由路由器和交换机发来的已过期的流量包的 data records exported by routers and switches consist of expired traffic flows with 详细的流量统计。 这些包包含关于源、目标IP地址以及所使用的协议、端口。These flows contain information about source and destination IP addresses along with the protocols and ports used in the end-to-end conversation.

This information assists IT in monitoring and fine-tuning network traffic by identifying additional bandwidth requirements, and allocating available bandwidth efficiently across the network.



  1. Time stamp of the flow流时间戳
  2. 源和目标IP地址
  3. 源和目标端口
  4. 输入和输出接口
  5. 下一跳IP地址
  6. Total bytes in the flow流的总大小
  7. Number of packets in the flow流中的包数
  8. First and last time stamps of packets switched as part of this flow
  9. 源和目标 AS,和前缀掩码
  10. 序列号(version 5 only)
For more information on Cisco NetFlow go to