Switch means "switch", which is a kind of device used for forwarding electrical (optical) signalsNetwork equipment. It can provide an exclusive electrical signal path for any twonetwork nodes connected to the switch. The most common switches areEthernet switches. Other common ones include telephone voice switches, fiber optic switches, etc.
Switching (switching) is a method that is completed manually or automatically by equipment according to the needs of both ends of the communication to transmit the information to the corresponding device that meets the requirements A general term for technologies on a> LAN function and can connect to a bridging . The switch has multiple ports, each of which has the data link layer function and is used in the information exchange A device that completes the ) is a kind of communication systemswitch. A wide area switch (LAN switches. Depending on the working location, switches can be divided into WAN switches and routingworkstation. In fact, switches are sometimes called multiport bridges.
Incomputer networksystem, the introduction of the switching concept has improved the shared working model. And HUBHub is a physical layer shared device. The HUB itself cannot recognize the MAC address and < a i=6>IP address, when host A in the sameLAN transmits data to host B, a>Data packets are transmitted in a broadcast manner on a HUB-based network, and are transmitted by each terminal. In layman's terms, ordinary switches do not have management functions. Just plug in one cable and connect the other interfaces to the computer. network bandwidth can be transmitted on the network at the same time. If a collision occurs, it must be retried. . This method is to sharedata frames Determine whether to receive by verifying the MAC address of the data header. In other words, in this working mode, only one set of
Experimental topology diagram
The basic switch configuration experimental topology diagram is as follows:
Purpose
- Understand the role of switches
- Master the basic configuration methods of switches
- Familiar with the use of experimental software
Experimental steps
Configuration command description
- The switch command mode includes user mode ">", privileged mode "#", and configuration mode "config"
- In any mode, the user does not need to enter the entire command when entering it, as long as the first few letters can uniquely identify the command, and then pressing the tab key will display the full name.
For example: interface serial 0/1 can be written as: int s 0/1
- In any mode, enter a "?" to display all commands in that mode.
- If you don't know how to spell a command, you can enter the first few letters, followed by "?", and the switch will display what commands match it.
- If you don't know what the parameters behind the command are, you can add a space after the keyword of the command and type "?", and the switch will prompt you what the corresponding parameters are.
Configuration content
- Understand the various modes of entry of the switch. When the switch command is turned on, it is in user mode:
enable(en): Enter privileged mode
conf t: Enter global configuration mode (enter in privileged mode)
interface vlan 1: Enter port configuration mode (enter in global configuration mode)
line console 0: Enter access configuration mode (enter in global configuration mode)
2. Modify the switch name and password. Set a password to return to user mode and enter privileged mode again. You need to enter a password. After the password is entered, it will not be displayed in the window. Press Enter to automatically enter the privileged mode.
Use "exit" to exit to the previous mode, and "end" to exit to the privileged mode.
Use show startup-config to view switch configuration file information, and show running-config to view all current configuration information.
To save the current configuration, use copy running-config startup-config (if not saved, the configuration will be lost after restarting).
Restart the switch using the reload command.
Note: The above three commands show, copy, and reload are all used in privileged mode.
3. The IP address configuration is as shown in the figure. The IP configuration is the management IP address of the switch, which is used to enable remote access from the PC.
Before configuration:
After configuration:
4.Telnet configuration
How to access the switch
1. Directly connect and log in through the Console port
This method is usually used when configuring the switch for the first time after buying it.
First, find the connection cable between the console port of the switch and the computer serial port, and then connect both ends to the console control port of the switch and the computer serial port respectively.
Turn on the switchPower supply, start the computer, and click "Start" → "Programs" → "Accessories" → "Communications" → "HyperTerminal" command to open the "HyperTerminal" program. Establish a connection to the switch. Students can find the specific methods by themselves.
2. Log in through Telnet
This method is suitable for remote management of switches. It requires that the switch has been configured with IP address information (switches generally have a default IP address), and a user account with administrative rights has been established.
1. Connect the computer to a common port of the switch, or ensure that the computer and the switch can be connected (for example, through a network connection).
2. Click the "Run" command in the "Start" menu, then enter the "telnet IP address" command, click the "OK" button to open the telnet window. After entering your username and password, you can configure the switch.
3. Log in through Web browsing
After setting the IP address information of the switch and enabling the HTTP service, you can access the switch through a JAVA-supported Web browser, and you can modify various parameters of the switch and manage the switch through the Web through the browser. In fact, through the Web interface, many important parameters of the switch can be modified and set, and the operating status of the switch can be viewed in real time.
1. Connect the computer to a common port of the switch, or ensure that the computer and the switch can be connected (for example, through a network connection).
2. Open a web browser, enter the IP address of the switch you want to log in to in the "Address" field of the browser (such as 172.20.1.211), and press the Enter key to pop up the login dialog box.
3. After entering the user name and password with administrative rights, click the "OK" button, and we can see the switch configuration interface.