41 LAN switches and their basic principles

LAN switches and their working principles
1. LAN switches: The main limitation of bridges is that they can usually only perform one frame forwarding operation at any one time, so LAN switches, also known as Ethernet switches, appear. Essentially, an Ethernet switch is a multi-port bridge that works at the data link layer. The switch can economically divide the network into small conflict domains and provide higher bandwidth for each workstation.
The Ethernet switch is transparent to the workstation, so the management overhead is low, which simplifies the increase of network nodes, movement and network transformation operations. The use of Ethernet switches can also easily implement a virtual local area network (Virtual LAN), VLAN can not only isolate the conflict domain, but also isolate the broadcast domain.
2. Principle The principle of an
Ethernet switch is that it checks the MAC (media access layer) addresses of the source and destination of the data frame from the Ethernet port, and then compares it with the dynamic lookup table inside the system. If the MAC address of the data frame is If it is not in the lookup table, add the address to the lookup table and send the data frame to the corresponding destination port.
3. Features
3.1 Each port of the Ethernet switch is directly connected to a single host, and generally works in full duplex mode.
3.2 The Ethernet switch can communicate with many pairs of ports at the same time, so that each pair of hosts that communicate with each other can transmit data without collision as an exclusive communication medium.
3.3 Ethernet switch is also a plug-and-play (same as transparent bridge), and its internal frame forwarding table is also gradually established through self-learning algorithm.
3.4 Ethernet switch uses a dedicated switching structure chip, Its high exchange rate is
3.5 Ethernet switches exclusively occupy the bandwidth of the transmission media.