What Are Router Metrics?

A router is a hardware device that connects two or more networks and acts as a gateway between the networks. It is a dedicated intelligent network device that reads the address in each data packet and then decides how to transmit it. It can understand different protocols, such as the Ethernet protocol used by a local area network and the TCP / IP protocol used by the Internet. In this way, the router can analyze the destination addresses of the data packets from various types of networks, convert the addresses of non-TCP / IP networks into TCP / IP addresses, or vice versa; and then, according to the selected routing algorithm, each data packet Best route to the designated location. So the router can connect non-TCP / IP network to the Internet.

A router can also be called a gateway device. The router is in

The devices in the network communicate with each other mainly by their

The main function of a router can be understood as the transfer of information. Therefore, we call this process the addressing process. Because the router is between different networks, it is not necessarily the final receiving address of the message. So in the router, there is usually a routing table. According to the final address of the information transmitted by the transmission website, find out which network should be the next forwarding address. In fact, it is as simple as express delivery company to send mail. The mail does not arrive at the final destination instantaneously, but is sorted by different sub-stations and continuously approaches the final address, thereby realizing the mail delivery process. The router addressing process is similar. The final address is matched in the routing table, and the next forwarding address is determined by the algorithm. This address may be the intermediate address or the final arrival address. ^[4]

(1) Functionally, it can be divided into: backbone-level, enterprise-level and access-level routers. Backbone router data throughput is large and important, which is the key to the interconnection of enterprise-level networks. Backbone routers require high performance and high reliability. Networks often use technologies such as hot backup, dual power supplies, and dual data paths to ensure reliability. Enterprise-level routers are connected to many end systems and are simple and have low data traffic. ^[5]

Traditional routers need to perform a series of complex operations when forwarding each packet, including route lookup, access control list matching, address resolution, priority management, and other additional operations. These operations greatly affect the performance and efficiency of the router, reduce the packet forwarding rate and forwarding throughput, and increase the burden on the CPU. The correlation between the packets before and after passing the router is very large. Packets with the same destination address and source address often arrive consecutively. This provides the possibility and basis for the fast forwarding of packets. New-generation routers, such as IP Switch and Tag Switch, use this design philosophy to implement fast forwarding with hardware, which greatly improves the performance and efficiency of routers.

New generation routers use forwarding buffers to simplify packet forwarding operations. In the fast forwarding process, only the first several packets of a group of packets with the same destination address and source address need to be subjected to traditional routing and forwarding processing, and the destination address, source address, and next gateway address of the successfully forwarded packet ( Next router address) into the forwarding buffer. When subsequent packets are to be forwarded, the forwarding buffer should be checked first. If the destination address and source address of the packet match the forwarding buffer, the packet will be forwarded directly according to the next gateway address in the forwarding buffer without going through traditional The complex operation greatly reduces the burden on the router, thereby achieving the goal of improving the throughput of the router. ^[7]

Practice shows that in the application of wireless networks

Router is a transitional tool for the network, and it also plays a very important role in the use of the network. Router vulnerabilities are mainly divided into password cracking vulnerabilities, web vulnerabilities, backdoor vulnerabilities, and overflow vulnerabilities, but most of the router vulnerabilities are related to the quality of the router. Each router has at least two ports connected to two networks. Good quality routers will use strict security mechanisms to protect themselves. At the same time, they will also protect the connected computer network to prevent passwords from being cracked. Or leave too obvious backdoors. In addition, the installation of network managers and routers should also protect the equipment to a certain degree, and isolate the danger from the root cause. For BGP vulnerabilities, the most effective solution is to solve the problem at the ISP level. At the network level, it is to monitor the routing of inbound data packets and search for any abnormal conditions to resolve them. At the same time, as the user of the router and the user of the network equipment, they should learn and understand the security performance of the router equipment, pay attention to the password settings of the router, etc., to avoid leaving opportunities for illegal personnel, and When there is a problem with the equipment, it is necessary to find relevant personnel in time to deal with and resolve it in a timely manner to minimize injuries and losses. ^[8]