What is the difference between a switch and a router in the equipment room?

Switches and routers are common network devices in the computer room. Many friends don't know that routers and switches are different. They often ask questions that seem ridiculous. As for the two guys, you are a couple, and the appearance is similar. Is it the same? what differences are there? It is not clear, in fact, there is a big difference between the router and the switch. This article gives you a detailed explanation of the difference between the two.

What is a switch?

A switch (English: Switch, meaning "switch") is a network device used for electrical signal forwarding. It provides an exclusive electrical signal path for any two network nodes that access the switch. The most common switches are Ethernet switches. Other common ones are dian voice switches and fiber switches.

What is a router?

A router is a device that connects to various local area networks and wide area networks in the Internet. It automatically selects and sets routes according to the channel conditions, and sends signals to the devices in order. The router is the hub of the Internet, "traffic jing". At present, routers have been widely used in various industries, and various grades of products have become the main force for realizing internal connections of various backbone networks, interconnecting backbone networks, and backbone network and Internet interconnection services.

The difference between routers and switches

The difference between a router and a switch

The switch works at the relay layer. The switch is addressed according to the MAC address. The router works at the network layer. According to the IP address addressing, the router can handle the TCP/IP protocol, but the switch cannot.

The difference between routers and switches

The switch is a network cable to go online, but everyone is dialing separately, each using their own broadband, and everyone has no influence on the Internet. The router has one more virtual dialing function than the switch. The computer that accesses the Internet through the same router shares a broadband account, and everyone has to interact with each other.

The difference between routers and switches

The switch can make multiple computers connected to it form a local area network. If there is a proxy server, it can also realize the simultaneous Internet access function and all the computers on the local area network share its bandwidth rate, but the switch does not have the router automatically recognizes the data packet transmission and arrival address. Features. The router can automatically identify the address where the packet is sent and arrived, and the router is equivalent to the jing inspection on the road, responsible for traffic guidance and guidance.

The difference between routers and switches

To give a few examples, the router is a small post office, an address (IP), responsible for sending and receiving a place (personal computer, a server, so your home Internet needs this thing), the switch is the province's big postal center, responsible for An address is given to the Lian department of each small place. Simply put, the router is dedicated to the network, the switch only manages the distribution, routing and routing is to find the way for you to access the Internet, the switch is only responsible for opening the door, there is no route on the switch, you can not get on the network.

The difference between routers and switches

The router provides the service of the firewall. The router only forwards the data packets of a specific address, and does not transmit the packet transmission that does not support the routing protocol and the transmission of the unknown target network data packet, thereby preventing the broadcast storm.

The difference between network switches and routers

A network switch is a network-expanding device that provides more ports for sub-networks to connect to more computers. With the development of the communication industry and the advancement of national economy information, the network switch market has shown a steady upward trend. It is characterized by high performance and price ratio, high flexibility, relatively simple, and easy to implement. Therefore, Ethernet technology has become the most important LAN networking technology, and network switches have become the most popular switches.

A router is a device that connects to various local area networks and wide area networks in the Internet. It automatically selects and sets routes according to the channel conditions, and sends signals in the order of the front and back. The router is the hub of the Internet, "traffic jing". At present, routers have been widely used in various industries, and various grades of products have become the main force for realizing internal connections of various backbone networks, interconnecting backbone networks, and backbone network and Internet interconnection services. The main difference between a route and a switch is that the switch occurs at the second layer (data link layer) of the OSI reference model, and the route occurs at the third layer, the network layer. This difference determines that routing and switches need to use different control information in the process of moving information, so the way they implement their respective functions is different.

The difference between a three-layer switch and a router

Although they all have routing functions, the main function of the Layer 3 switch is still data exchange. Its routing function is usually simple, because it is mainly a simple LAN connection. The routing path is far less complicated than the router. It uses The main purpose of the LAN is to provide fast data exchange functions to meet the application characteristics of frequent LAN data exchange.

The main function of the router is the routing function. Its routing function is more reflected in the interconnection between different types of networks, such as the connection between the LAN and the WAN, the connection between the networks of different protocols, etc., so the router is mainly used. Between different types of networks. Its main function is routing and forwarding. It is the ultimate goal to solve the connection of various complex routing path networks. Therefore, the routing function of the router is usually very powerful, not only applicable to the LAN of the same protocol, but also suitable for different protocols. Between the LAN and the WAN. Its advantage lies in the choice of routers such as zui good routing, load sharing, link backup and exchange of routing information with other networks. In order to connect with various types of networks, the interface type of the router is very rich, and the three-layer switch is generally only the same type of LAN interface, which is very simple.

Technically, routers and Layer 3 switches have significant differences in packet switching operations. Routers typically perform packet switching by a microprocessor-based software routing engine, while Layer 3 switches perform packet switching through hardware. After the Layer 3 switch routes the first data stream, it will generate a mapping table of MAC addresses and IP addresses. When the same data stream passes again, it will pass directly from Layer 2 instead of re-routing according to this table. Therefore, the delay of the network caused by the routing of the router is eliminated, and the efficiency of packet forwarding is improved. At the same time, the route lookup of the Layer 3 switch is for data flow. It utilizes the cache technology and is easy to implement by using ASIC technology. Therefore, it can greatly save costs and achieve fast forwarding. The forwarding of the router adopts the longest matching method, which is complicated to implement, and is usually implemented by using software, and the forwarding efficiency is low.

For this reason, the performance of the Layer 3 switch is much better than that of the router when compared with the overall performance. It is very suitable for LANs with frequent data exchange. However, although the routing function is very powerful, its packet forwarding efficiency is much lower. Layer 3 switches are more suitable for the interconnection of different types of networks where data exchange is not very frequent, such as the interconnection between LAN and Internet. If a router, especially a high-end router, is used in a local area network, it is a waste to a considerable extent (in terms of its powerful routing function), and it does not satisfactorily meet the communication performance requirements of the LAN, affecting the subnets. In general, as described above, multi-subnet connections are made in the local area network, and the three-layer switch is also selected, especially in an environment where data exchange is frequent in different subnets. On the one hand, it can ensure the communication performance requirements between subnets, on the other hand, it saves the investment of purchasing switches. Of course, if the communication between subnets is not very frequent, it is understandable to use routers, and the purpose of subnet security isolation and mutual communication can also be achieved. The specifics should be determined according to actual needs.

The biggest difference between Layer 3 switching and routing is that routing supports nat conversion, while Layer 3 does not. In the actual project, it is reflected in the fact that the optical fiber can be connected to the Internet directly on the route, and the fiber can be connected to the Layer 3 device without accessing the Internet. Each of the three layers has a dedicated mac address and a dedicated ASIC integrated circuit.

The difference between a router and a cat

The purpose of the router and cat is different from the link location.

Router: The role of the router is to make a network cable allow several computers to access the Internet at the same time, which plays a role of distribution. Connect the cat above and connect the computer below.

The cat calls the modem, and the computer can dial the Internet through it. Connect the dian phone line above, connect the router below, the shape and port of the router and cat are different, the router's shape and port (wired router and wireless router) router is divided into wired router and wireless router, wired router with 4 port, 8 port Most common; wireless routers are the most common with 4 ports, with obvious antennas as identification marks.

Cat's shape and port, commonly used cat ports, one for dian phone line, one for RJ-45 port (network cable), and a cat with router function, router and cat as one, this is rare This cat has the dual characteristics of a cat and a router. There are many ports, one for the dian phone line and four for the network cable interface.