USIO21  交换机 可以完成信息交换功能的设备

USIO21交换机是一种通信系统中完成信息交换功能的设备。在计算机网络系统中，交换机是针对共享工作模式的弱点而推出的。 交换机的所有的端口都挂接在这条背部总线上，当控制电路收到数据包以后，处理端口会查找内存中的地址对照表以确定目的MAC（网卡的硬件地址）的NIC（网卡）挂接在哪个端口上，通过内部交换矩阵迅速将数据包传送到目的端口。 目的MAC若不存在，交换机才广播到所有的端口，接收端口回应后交换机会“学习”新的地址，并把它添加入内部地址表中。

USIO21交换机的工作原理： 交换机内部有一个地址表，这个表标明了MAC地址和交换机端口的对应关系。 接着读取包头中的目的MAC地址，并在地址表中查找相应的端口，若表中有与该目的MAC地址对应的端口，则把数据包直接复制到这个端口上，若表中找不到相应的端口则把数据包广播到所有端口上，当目的地址对源机器回应时，USIO21交换机又可以学习到目的MAC地址与哪个端口对应，若下次再向该数据端口发送数据时就无需再向所有端口进行广播了。

此外，USIO21交换机的应用广泛，常见的有以太网交换机、电话语音交换机、光纤交换机等。以太网交换机是最常见的交换机类型，它能提供以太网接口和用于连接不同类型的网络设备。电话语音交换机主要用于语音通信，它能够连接电话线路和其他语音通信设备。光纤交换机则以光纤为传输介质，用于高速数据传输和大规模网络连接。

USIO21  交换机 可以完成信息交换功能的设备

USIO21 switch is a device that completes the function of information exchange in a communication system. In the computer network system, the switch is introduced for the weakness of the shared working mode. All ports of the switch are connected to this back bus, when the control circuit receives the data packet, the processing port will look up the address mapping table in memory to determine the destination MAC (network card hardware address) NIC (network card) is connected to which port, through the internal exchange matrix quickly transmitted the data packet to the destination port. If the destination MAC address does not exist, the switch broadcasts to all ports. After receiving the response from the port, the switch learns the new address and adds it to the internal address table.

How the USIO21 switch works: There is an address table inside the switch that indicates the relationship between the MAC address and the switch port. Then read the destination MAC address in the packet header, and look for the corresponding port in the address table, if there is a port corresponding to the destination MAC address in the table, the data packet is directly copied to this port, if the corresponding port is not found in the table, the data packet is broadcast to all ports, when the destination address responds to the source machine, The USIO21 switch can also learn which port corresponds to the destination MAC address, and the next time it sends data to this data port, it does not need to broadcast to all ports.

In addition, USIO21 switches are widely used, common Ethernet switches, telephone voice switches, Fibre Channel switches and so on. Ethernet switches are the most common type of switches that provide Ethernet interfaces and are used to connect different types of network devices. Telephone voice exchange is mainly used for voice communication, which can connect telephone lines and other voice communication devices. Fibre Channel switches use optical fiber as the transmission medium for high-speed data transmission and large-scale network connections.