What is the role of network switches?

The interchange is a network connection device. Its main functions include physical addressing, network topology structure, incompetence verification, frame sequence, and flow control. The interchange also has some new functions, such as the rich Ethernet interchange in addition to the basic functions, as well as support for VLAN (virtual LAN) and supporting links to the links.

Learning: Ethernet AC machine understands the MAC address of each port connected device, and maps the address to the corresponding port to store in the MAC address table in the interchange cache.

Forward/filtration: When the intent of a data frame is mapping in the MAC address table, it is forwarded to the port of the connection intention node instead of all ports (such as the data frame is broadcast/broadcast frame, and forward to all ports) to all ports) Essence

Elimination circuit: When the interchange contains a redundant loop, the Ethernet AC machine is agreed to have a reserve way by generating a tree protocol to avoid the occurrence of the circuit.

In addition to connecting the same type of network, the interchange can also play a role in connecting between different types of networks (such as Ethernet and Quick Ethernet). Many interchange machines can now provide high -speed connection ports such as Ethernet or FDDI, which can be used to connect other interchange machines in the network to provide additional bandwidth for the key server with a large bandwidth.

Generally speaking, each port of the interchange is used to connect an independent network segment, but sometimes in order to supply faster access speed, we can directly connect some major network computers to the port of the interchange. In this way, the key server and major users of the network have a faster access speed to support greater information flow.

In the end, the basic function of the interchange is summarized:

1. Like a hub, the interchange provides a large number of ports that can be connected to the cable, so that the star topology wiring can be selected.

2. Like the relay, hub, and net bridge, when it forwards the frame, a square electrical signal occurs from the time from scratch.

3. Like the net bridge, the interchange uses the same forwarding or filtering logic on each port.

4. Like the network bridge, the interchange divides the local area network into multiple resistance. Each resistance is independent broadband, so it greatly improves the bandwidth of the local area network.

5. In addition to the functions of network bridges, hubs and relatives, the interchange also provides more advanced functions, such as virtual LAN (VLAN) and higher performance.