What Is a WLAN Router?

A wireless router is a router with wireless coverage for users to access the Internet.

Wireless Router

wireless

Intelligent management equipment

Dual WAM3.75G wireless-N broadband

wireless setting

1. SSID

In addition to the common ones introduced above

use

along with

Wireless router hardware failure

The router's hardware includes RAM / DRAM, NVRAM, FLASH, ROM, CPU, various ports, as well as the motherboard and power supply. Hardware faults can generally be seen on the LED indicators. For example: There is a green PWR (or POWER) status indicator on the power module. When this indicator is on, the power supply is working normally.

ONLINE and OFFLINE indicators and TX, RX indicators on the interface module. The Rx indicator is green to indicate that the port is receiving data packets; if it is orange, it indicates that it is receiving flow-controlled packets. The Tx indicator is green to indicate that the port is sending packets; if it is orange, it is to send flow-controlled packets. Different routers have different indicators to indicate different meanings, so you'd better read the manual first.

Hardware failures can sometimes be found in the boot log or seen during configuration. Since the router first performs hardware power-on self-test when it starts, it runs the hardware detection program in ROM to check whether each component can work normally. After the hardware test is completed, the software initialization is started.

If the router can detect a hardware failure during startup, it will be recorded in the system's startup log for later inspection. If when you configure the router, when you enter a certain port configuration, the system keeps reporting an error, then there may be a problem with the port. In addition, it is necessary to construct the operating environment of the router, such as: lightning protection grounding and stable power supply, indoor temperature, indoor humidity, electromagnetic interference, and static electricity, to eliminate all possible hidden troubles.

Wireless router system is missing

This refers to IOS (Internetwork Operating System), which is the basis for all configuration and operation of the router-the operating system. It is stored in the FLASH, sometimes due to operation errors or other unexpected reasons (such as: sudden power failure), the IOS in the FLASH is lost, resulting in the router not starting normally.

When this happens, you can also use the backup operating system software stored in ROM. This backup IOS is usually a little lower than the IOS version in FLASH, but it is enough for the router to start and work. In order for the router to work properly, you must re-download the new IOS to the FLASH. If the FLASH space is large enough, you can also save multiple IOS software and choose which version of the system to use. In order to be able to recover quickly after such a failure, it is best to save the IOS software on a secure server for urgent needs.

Wireless router system defects

Just like the WINDOWS system is often crashed by various viruses, the system defect of IOS will also cause the router to be paralyzed. For example, the red code has restarted some famous brand routers. IOS also has security flaws. If you do nt upgrade in time, the bad guy will use your router as his target. With the development of routers, by 2013, some routers have automatic defense functions, such as resisting DOS attacks and preventing password guessing.

IOS system defects are usually not fixed through patches, but replaced with brand new IOS. Once a system bug is found, the router manufacturer will promptly announce the bug, the affected system, and the corresponding new IOS software on the website. You must choose the version that suits your router model.

Cisco has stated that they will use "zero-fault" high-end router software, which can eliminate data or information loss failures caused by circuits or human factors. Even if an error occurs, packets can still be forwarded, which can prevent the network from appearing. Failure, which will reduce the burden on the network management.

Lost wireless router password

There are two places to set the password in the router.

From the previous introduction, there are two basic access modes when accessing the router:

User mode and management mode.

For security reasons, a password is required when entering both modes. Although everyone knows that the password is the key of the administrator with the most privileges, some people will forget it. Someone even set the password so simple that a hacker maliciously entered and changed the password. In fact, as long as we are careful, these low-level errors can be avoided.

In case the password is lost, don't be afraid, because the router provides a password recovery method. In addition to the two basic access modes (user mode and management mode) of the router, there is also a RXBOOT mode, in which you can easily recover the router password. Of course, it can only enter after the computer establishes a HyperTerminal connection through the CONSOLE port. Some routers also provide a more convenient RESET button on the panel. Just reset it a few times to restore the original password.

Wireless router configuration file is missing

This is also a frequent failure. First look at the startup process of the router:

System hardware power-on self-test. Run the hardware detection program in ROM to check whether each component can work normally. After completing the hardware test, proceed to the next step.

Run the BootStrap boot program in ROM.

Find and load IOS system files.

After IOS is loaded, the system first searches for the saved Startup-Config file in NVRAM to configure the system. If a Startup-Config file exists in NVRAM, the file is transferred to RAM and executed one by one. Then follow the commands in the configuration file to set the interface address and route processing. If the Startup-Config file cannot be successfully booted, the system enters the Setup mode to perform the initial configuration of the router in a man-machine conversation.

That is to say, if the startup configuration file is lost, the system cannot configure the router specifically and cannot complete the required functions. To restore the configuration file, you must first connect to the router and copy the backup configuration on the computer to NVRAM via TFTP. So every time we modify the configuration of the router, we must do a backup job.

Wireless router configuration error

When any administrator is new to the router, he or she will encounter various unexpected configuration errors, such as incorrect routing protocol configuration, incorrect IP address and mask, ACL (access control list) errors, and no configuration changes after modification. For example, an access control list error is a typical configuration error.

ACL is a set of command list applied to a certain interface of the router. This list tells the router which data packets should be received and which must be banned, so as to achieve the effect of data filtering. This is an effective way to control network security. The writing of this list involves the parameters of source address, destination address, and port number.

ACLs are executed sequentially, and at the end of all ACLs there will be a default, invisible "deny any" statement, which prohibits any communication. So when defining an ACL, there must be at least one PERMIT statement, otherwise the access list is meaningless. It is also possible to write the wrong port number used in the ACL, the order of the ACL statement is incorrect, or the wildcard (WILDCARD, which may be confused with the mask) is incorrect, the interface application is incorrect (the OUT and IN are confused), and so on. These configuration errors are inevitable. The key is whether we can learn the correct configuration from these mistakes again and again.

External factors of wireless router

This means that factors other than the router are causing the suspected router failure. For example, the network card of the client computer is faulty, the cable connector is incorrect, and cable crosstalk may cause data collisions, increased network traffic, increased router load, slowed down or even paralyzed the network. If the WAN port line of the dial-up router fails, dial-up will fail.

The wireless term related to the wireless router explains the wireless network service set identification (SSID) of the wireless router.

The wireless network service set identifier (SSID) can be specified as needed, for example, the wireless network service set identifier (SSID) is specified as a company name or other. In order to ensure that the wireless network card roams between different APs, the same wireless network service set identifier (SSID) needs to be set for these APs; otherwise, roaming cannot be supported. Similarly, the wireless network service set identifier (SSID) of the network card needs to be set to be the same as the wireless network service set identifier (SSID) of the AP, otherwise it will not be accessible.

Wireless router channel

If there is only one AP in the same area, the channel of the AP is optional, and the default setting is "Auto Select". If there are several APs in the same area at the same time, you need to configure the channel of each AP to minimize the frequency interference between neighboring APs. In general, for standard products, if 3 APs are placed in the same area, the channel can be set to 1, 6, 11, or 13 so that it will not cause interference.