Change the machine, hub, and router distinguishing hub (HUB) is a form of a repeater. It works in the physical layer, like a repeater, often used for bidirectional forwarding between the physical signals between the two network nodes. Complete the copy, adjustment, and enlargement of the signal. Different is that HUB can provide multi-port services. Switch (Switch) is similar to HUB, connecting two local area network segments. It works in the data link layer to function as a filter frame. Switch detects the source address and destination address of the frame. If you don't forward it in the same network segment. If not in the same network segment, turn the frame to another network. Several or hundreds of computers have made a local area network, and several HUBs can be connected. Say from a price perspective. Hub has the advantages of cheap, i.e., use. But this way to form a local area network is just the simplest topology. This peer can only complete simple data sharing. This is not enough for companies that need advanced network management. Any company is developing, and the application of the company's local area network will be more rich. There are more and more PCs in the local area network, and the division of labor is more clear, making the topology of the network more complex. Network reasonable architecture is to fully consider compatibility and scalability. In addition, consider the bandwidth balance between the backbone and the backbone and the stability of different network media on different transmission distances, so that the connection of the main dry network and the backbone network can meet the needs of bandwidth and meet different transmission distances. . Such a system integrates complex, planning a reasonable network, HUB is no longer competent. Therefore, Switch will become preferred. Comparison Description HUB and Switch Difference 1 During the transfer of data. Because of blocking, delay, etc. Short frames, debris, etc. will occur. As seen from the ISO physical system, the HUB belongs to the physical layer. The physical layer provides a basic mechanism that encodes binary data (bit) (sends to physical media) and decoding (received from physical media), the physical layer also defines the physical connection mechanism of the medium, but is not the medium itself. Therefore, HUB only performs a single synchronization, amplification, shaping, and short frames in the data, and fragments cannot be processed. Switch works in the data link layer. This layer provides a frame composed of information bits, the frame consists of a header or header, addressing information, and (for LAN) one 32-bit cyclic redundancy (CRC). The role of CRC is to ensure the integrity of the frame when the information bits pass through the physical media. The data link layer also provides link management. For Ethernet, the frame is transmitted when the channel is idle, and stops when the conflict is detected. In the token ring network. Frame transmission is performed when a free token is received. Therefore, the switch can not only synchronize data, enlarge, plastic, and can effectively filter short frames, fragments. 2 The increase in workstations on the company LAN, data communication will be more busy. When Hub works, no matter how many ports are communicating, all ports share a bandwidth. It uses a manner that is processed. For Switch, each port monitors a bandwidth, and the two arbitrary ports can communicate at any time and will never affect other ports. This makes Switch work more smooth than HUB. Of course, all mainstream Switch support 10M / 100M adaptive, not only can work in half-duplex, but also work in full-duplex mode. 3 When a port of the HUB transmits data, the destination port is not active, but is sent to each port. Imagine, a workstation transmits data to another workstation. This information frame will spread throughout the network through HUB. White wasts bandwidth resources. Use the Switch connection network segment, if the source port is in the same network segment in the same network segment, the information will not enter another network segment via Switch.
