Cisco fast forward transmission (CEF) and NetFlow services

In this era of rapid development of Internet-based e-commerce, it is a challenging task to gain a firm foothold in the fierce competition environment. Therefore, service providers and enterprises must pay close attention to the latest development of Internet-related technologies. We have noticed that Cisco's IOS switching architecture has recently introduced two new technologies: Cisco fast forward transmission CEF) and network data flow NetFlow) services.

CEF Technology

With the increasing popularity of networks, the Internet data transmission mode has changed significantly. Data is frequently moved between different networks, which causes a large number of IP data packets with short-lived periods in the network. In terms of topology, their destination addresses are often very different. In this context, CEF is mainly used to optimize network data transmission features.

CEF is a fully topology-based architecture. In the past, the exchange system used the first packet in the data stream to establish the buffer zone of the IP destination address, and then the subsequent data packets were transmitted to the address; CEF uses all valid routing information to establish an optimized IP forward information library FIB), uses FIB, even for data initialized in the first packet, A vswitch or vro can still quickly find an optimal path for network transmission. In fact, CEF has become an efficient Internet switching architecture.

NetFlow technology　

Like CEF, NetFlow is also a new technology that is gradually being improved. NetFlow provides network capacity planning, trend analysis, and data priority information for service providers and enterprises. This technology can also be used for IP-based billing applications and service level SLA validation services.

NetFlow is mainly used to record the data of the initialized IP packet, such as the IP protocol type, service type ToS, and interface ID. Then, to effectively match and count data, NetFlow allows subsequent data to be transmitted in the same data stream and uses their respective services, such as security filtering, QoS policies, and traffic planning. Real-time data is stored in the NetFlow cache and can be retrieved by reading operation commands.

On the basis of NetFlow, Cisco also proposed the NetFlow Policy Routing Technology. This Cisco IOS Service-based technology provides traffic planning and IP pre-classification functions, providing an efficient and high-performance NetFlow mechanism for policy routing. Since it also supports the CEF architecture, it can be used on distributed platforms.

1. NetFlow technology and network traffic analyzer
2. NetFlow exchange and Its Application in Network Management