You use any form of Internet access, may encounter: slow Internet access (can not browse the web, card, Internet access, poor signal, signal delay, connection failure, instability, packet loss, high error rate, Internet access, dropped, crash, interruption without reason......) The phenomenon such as;
The following conditions must be met when the computer runs stably:
A: necessary environmental conditions:
A: Stable power supply voltage (with auxiliary UPS power supply if necessary), effective power line section; Comply with safety insulation class regulations.
B: The temperature of drying and ventilation is suitable (fan or air conditioning system should be installed if necessary).
C: For smaller dust particles, the wall and roof had better be painted.
D:. Suitable signal-to-clutter ratio for transmission lines.
E: Network adapter problem: Choose a good network adapter.
F: Software configuration: the software is legal; If you do not need to set an IP address, the system automatically assigns it to you. If you want to set DNS correctly. The system is WIN98 or ME. In DOS, type WINIPCFG to obtain the DNS domain. For WINXP, type IPCONFIG. Software Settings to be reasonable: ADSL users appear local connection to accept restrictions or no connection, there will be a prompt, does not affect the Internet, ADSL users are dial-up Internet access and automatically assign IP, do not want to let it appear, you can: Right-click Network Neighbor - Properties - Local Area Connection - Properties - Double-click Internet Protocol (TCP/IP) - Use the following IP address: IP address: 192.168.1.120 Subnet mask: 255.255.255.0 Gateway: 192.168.1.1 Click OK.
G: TCP/IP: If the browsing is abnormal, delete TCP/IP and add TCP/IP again.
H: Influence of humidity: in rainy season, rainy days and areas with high humidity, the insulation of the line is reduced and the signal level drops, leading to disconnection or unstable operation. Humidity accelerates oxidation, interrupting transmission.
I: The impact of temperature: low temperature in winter, fewer cat problems; Summer temperature is high, "cat" afraid of "fever".
J: After the network is opened, all the original technical data will be used for comparative analysis and fault judgment and location.
Two: good grounding system:
According to the regulations (grounding device construction GB50169-92) requirements: there must be more than two "independent" grounding pole (can not be common "ground"), grounding pole to the work site of the lead section is not less than 16 mm square multi-strands of copper wire, each "independent" grounding resistance of the grounding pole shall not be greater than 5 ohm. The subscriber line shielding layer is grounded immediately to reduce interference to a minimum; The ground of water pipe and electric power (N line) should not be used as grounding pole. The grounding wire should not be wound. It should be coated with silver powder conductive paste and fastened with screws. Lightning: to disconnect all lines connected with the outside world, to avoid equipment accidents, to avoid fire accidents.
Three: the system is clean and neat:
Clothes do not lie in the class of clothes, but in whether clean and neat;
Therefore:
A: Legitimate software, timely update patches; Delete unused files, timely clean up Internet garbage and regularly defragment, optimize system structure;
B: Legitimate and effective anti-virus software, often upgrade virus library; If the firewall, shared Internet access software, and network acceleration software are properly configured, users may be affected.
C: Do not put non-running software and other files into the operating disk or desktop; If you open some software, the connection will drop. Uninstall the software.
D: The computer (including auxiliary) equipment should be monitored and maintained in order to ensure that the equipment is clean, well ventilated, the connection contact resistance should be as small as possible, the temperature and humidity should be moderate, the insulation should be good, and the wiring should be neat and beautiful.
4: good links: check the host and assist the keyboard, mouse, speakers, R45 joint (five categories) network line, grounding line, power supply multi-purpose board, the power cord, etc.) must be good (contact resistance in Ω), check the door line joints, such as telephone line plug whether contact (Ω) and reliable, in order to reduce machine line fault; Wiring: even and vertical, clear and tidy (not wound).
Five: receiving level under bad conditions (wireless network card is: receiving field intensity, optical end machine is: receiving optical power level). Wireless users: because the user terminal is different from the base station, the receiving field intensity level is not the same; Therefore, terminal AGC and base station AGC are particularly important. The computer of the client should cooperate with the AGC of the operator's equipment, so that the computer can reliably receive useful signals (high signal clutter) under different field intensities.
Six: The greater the out-of-band isolation, the better, the smaller the in-band attenuation: xDSL, broadband, wireless, optical fiber and other users, should provide the minimum in-band attenuation (less than 1dB), out-of-band isolation (more than 60dB). The signal-to-clutter ratio is also greater than 60dB.
Notebook can search wireless signal, cannot connect to the Internet how to solve
Case 1: whether there is a prompt to input the password of wireless connection when wireless connection is connected to the server. If you are not asked to enter a password for your wireless connection, you will need to change the security mode of your wireless Settings. The wireless network card of many old laptops does not support the latest WPA2 encryption, so you need to lower the wireless security encryption level.
When connecting to the wireless network, it always says "waiting for the network", and then the small wireless computer in the lower right corner of the computer is always marked with a cross. Or it says, "Your network is not in the service area," and you may be controlling the computer's MAC address in wireless control, which should be turned off. It may also be that the wireless signal is weak, resulting in the failure to connect to the operator. You can let the customer be closer to the operator to connect. (Generally speaking, there are two bars of signal can be connected properly)
Case three: the display has been "obtaining network address", and then "this connection accept", or the connection is disconnected.
This situation is generally wireless password input errors, such as forgetting the password, the letter is not case-sensitive. Ask the customer to reconfirm the password and re-enter it. If necessary, the customer can go to the setup page of the server to view the password. And write down the password, refresh the network, connection, enter a new password.
Solve this problem from the following aspects:
1. Whether the configuration of wireless network adapter is consistent with that of front-end server (password and encryption mode)
How to obtain the router address 2, whether to shut down the DHCP server, let the client use the connection server, local connection IP address with automatic access, see whether you can get the IP address, if the access, it did not close the DHCP server, if not, the prompt, that is shut down the DHCP server, You need to teach users about the DHCP server.
This prompt appears, you need to set up on the computer, right click "Wireless Network Connection" - > "Properties" - > "Wireless Network Configuration" - > "Preferred Network" - > double click the network to connect - > verify (here to disable IEEE802.1x authentication for this network (E))
Last resort:
If you still can't connect, reset the wireless transmitter and reset it again.
Teach you to remove ARP virus in LAN
Nowadays, there are many cases of ARP virus infection in local area network. It is difficult to clean up and prevent ARP virus, which causes a lot of troubles to many network administrators. The following is some personal experience in dealing with this problem, but also on the Internet browsing a lot of reference materials.
Nowadays, there are many cases of ARP virus infection in local area network. It is difficult to clean up and prevent ARP virus, which causes a lot of troubles to many network administrators. The following is some personal experience in dealing with this problem, but also on the Internet browsing a lot of reference materials.
ARP virus symptoms
Sometimes the Internet is not normal, sometimes there is a good, including access to the Internet neighbor is also so, copy files can not be completed, there are errors; The number of ARP packets on the LAN increases rapidly. When you query ARP packets, abnormal MAC addresses or incorrect MAC addresses may be found, and one MAC address may correspond to multiple IP addresses.