Characteristics and functions of routers

The router has the function of judging the network address and selecting the IP path. It can establish flexible connections in the multi internetworking environment, and can connect various subnets with completely different data packets and media access methods. The router only accepts information from the source station or other routers, which is an interconnection device at the network layer. It does not care about the hardware devices used by each subnet, but requires running software that is consistent with the network layer protocol.

Routers are divided into local routers and remote routers. Local routers are used to connect network transmission media, such as fiber optics, coaxial cables, and twisted pair cables; Remote routers are used to connect remote transmission media and require corresponding devices, such as telephone lines equipped with modems and wireless receivers and transmitters. 4G Cat4 Cpe

Routers are the main node devices of the Internet. The router determines the forwarding of data through routing. The forwarding strategy is called routing, which is also the origin of the router name (router, forwarder). As a hub for interconnecting different networks, router systems form the main backbone of the TCP/IP based international internet, which can also be said to form the backbone of the internet. Its processing speed is one of the main bottlenecks in network communication, and its reliability and stability directly affect the quality of network interconnection. 4G CAT6 CPE

Therefore, router technology has always been at the core position in the field of campus intranet, regional intranet, and even the entire Internet research. Its development process and direction have become a microcosm of the entire Internet research. At a time when network infrastructure and information construction are in the ascendant in China, exploring the role, status, and development direction of routers in interconnected networks is of great significance for domestic network technology research, network construction, and clarifying the various paradoxical concepts of routers and network interconnection in the network market. 4G MIFI

In recent years, switch router products have emerged. Essentially, they are not new technologies, but rather combine the principles of switches into routers to improve communication capabilities, making data transmission faster and better.

Router function:

Connect different networks

From the perspective of filtering network traffic, the role of routers is very similar to that of switches and bridges. However, unlike switches that work at the physical layer of the network and physically partition network segments, routers use specialized software protocols to logically partition the entire network. For example, a router that supports the IP protocol can divide the network into multiple sub network segments, and only network traffic directed to a specific IP address can pass through the router. For each received packet, the router recalculates its checksum and writes a new physical address. Therefore, the speed of forwarding and filtering data using routers is often slower than switches that only view the physical addresses of data packets. However, for networks with complex structures, using routers can improve the overall efficiency of the network. Another obvious advantage of routers is their ability to automatically filter network broadcasts. Overall, the entire installation process of adding routers to the network is much more complex than that of plug and play switches.

Select the route for information transmission

Some routers only support a single protocol, but most routers can support the transmission of multiple protocols, namely multi-protocol routers. Due to each protocol having its own rules, completing algorithms for multiple protocols in a single router will inevitably reduce the performance of the router. The main job of a router is to find the best transmission path for each data frame passing through the router and effectively transmit that data to the destination site. From this, it can be seen that the strategy of selecting the best path, namely the routing algorithm, is the key to routers. In order to complete this task, the router stores various transmission path related data - Routing Table - for use in routing selection. The path table stores information such as subnet flags, the number of routers on the network, and the name of the next router. The path table can be fixed by the system administrator, dynamically modified by the system, automatically adjusted by the router, or controlled by the host.

Static routing table: A fixed path table set by the system administrator in advance is called a static path table. It is generally set according to the network configuration during system installation and will not change with future network structure changes.

Dynamic routing table: A dynamic path table is a path table that routers automatically adjust based on the operation of the network system. The router automatically learns and remembers the network operation based on the functions provided by the Routing Protocol, and automatically calculates the optimal path for data transmission when needed.