Broadly speaking, there are two types of network switches: WAN switches and LAN switches. WAN switches are mainly used in the telecommunications field to provide a basic platform for communications. The LAN switch is used in the local area network to connect to terminal equipment, such as PCs and network printers. From the transmission medium and transmission speed, it can be divided into Ethernet switches, fast Ethernet switches, Gigabit Ethernet switches, FDDI switches, ATM switches, and token ring switches. From the scale of application, it can be divided into enterprise-level switches, department-level switches, and workgroup switches. The scales of different manufacturers are not completely the same. Generally speaking, enterprise-level switches are rack-mounted, and department-level switches can be rack-mounted (with a small number of slots) or fixed-configuration type. The level switch is a fixed configuration type (the function is relatively simple). On the other hand, from the perspective of application scale, when used as a backbone switch, a switch that supports large-scale enterprise applications with more than 500 information points is an enterprise-level switch, and a switch that supports medium-sized enterprises with less than 300 information points is a department-level switch, and 100 Switches within this information point are workgroup-level switches.
With the rapid development of computers and their interconnection technology (also known as "network technology"), Ethernet has become the short-distance Layer 2 computer network with the highest penetration rate so far. The core component of Ethernet is the Ethernet switch.
Whether it is manual switching or program-controlled switching, it is for the transmission of voice signals, and it is a "circuit switching" that requires an exclusive line. The Ethernet is a computer network, which needs to transmit data, so it uses "packet switching." But no matter which switching method is adopted, the switch's feature of providing "exclusive access" between two points will not change. As far as Ethernet equipment is concerned, the essential difference between a switch and a hub is that when A sends a message to B, if it passes through the hub, all network nodes connected to the hub will receive this information (that is, it will be sent in the form of broadcast) , But the network card at the hardware level will filter out the information that is not sent to the machine; and if it passes through the switch, unless A informs the switch to broadcast, otherwise the information sent to B will never be received (obtaining the control authority of the switch to monitor the situation except).
According to market demand, Ethernet switch manufacturers have introduced three-layer or even four-layer switches. But in any case, its core function is still Layer 2 Ethernet data packet switching, but with a certain ability to process data packets at the IP layer or even higher layers. The network switch is a device that expands the network and can provide more connection ports in the sub-network to connect more computers. With the development of the communications industry and the advancement of the informationization of the national economy, the network switch market has shown a steady upward trend. It has the characteristics of high performance-price ratio, high flexibility, relatively simple, and easy to implement.
Optical switch
Optical switching is a next-generation switching technology being developed. All switching technologies are based on electrical signals. Even fiber optic switches convert optical signals to electrical signals, and after switching processing, the optical signals are then converted back to another optical fiber. Due to the low photoelectric conversion rate and the physical bottleneck of the circuit processing speed, people hope to design an "optical switch" that does not require photoelectric conversion. The internal part is not a circuit but an optical circuit, and the logic element is not a switching circuit. It is the switch optical path. This will greatly increase the processing speed of the switch.
Remote configuration
In addition to the direct connection of the switch to the computer through the "Console" port, it can also be connected through an ordinary port. At this time, you cannot use local configuration to configure the switch. Instead, you need to implement the switch configuration through Telnet or a Web browser. The specific configuration method is as follows:
1. Telnet
The Telnet protocol is a remote access protocol through which you can log in to the switch for configuration.
Assuming that the IP of the switch is: 192.168.0.1, it only takes two steps to configure the switch through Telnet:
Step 1, click start, run, enter "Telnet 192.168.0.1"
Step 2, After inputting, click the "OK" button, or click the Enter key to establish a connection with the remote switch. Then, you can configure and manage the switch according to actual needs.
2. Web
Through the web interface, you can set the switch as follows:
Step 1. Run the web browser, enter the switch IP in the address bar, press Enter, and the following dialog box will pop up.
Step 2. Enter the correct user name and password.
The third step, the connection is established, you can enter the switch configuration system.
Step 4, follow the prompts to set the switch and modify the parameters.