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How to maximize the speed and performance of the network has always been a concern of enterprise network managers. This paper will focus on how to further improve the speed and performance of the network, and give seven suggestions from industry veterans and network experts.

Using jumbo packets

Using giant packet technology can improve the performance of the network. Switches and network interface cards that support jumbo packets can handle packets whose maximum length exceeds the IEEE standard (1.5kbit). Some devices support packets longer than 9k bits, but there is no uniform standard for the length of jumbo packets. Insiders pointed out that jumbo packet technology is more effective for high-speed Ethernet such as Gigabit network and 10G network, and many manufacturers including 3Com, Cisco and Jisu Network have provided products supporting this technology. The network using this technology should set the switch to jumbo packet mode, and must use the products of the same manufacturer, otherwise there may be problems such as packet loss or decomposition. At the same time, experts suggest that the application scope of jumbo packet technology should be limited, for example, it should only be used for network connections such as file transfer or backup work from server to server.

Check the network connection

The decline of network performance may be due to simple physical connection problems, but network administrators can't ignore these problems, because the damage of cables or connectors may only lead to the loss of data packets, and will not completely paralyze the network, so such problems are more hidden. Network sniffers can be used to detect abnormal packet retransmissions, which is usually a sign of cable problems. Environmental factors may also cause the decline of network performance, such as cables or heating systems near elevators, which will be affected by electromagnetic fields when transmitting data. Experts suggest that cables in this environment should be equipped with protective shells, and it is best to upgrade all cables in the network to Category 5 or Category 6 cables.

Use full duplex mode

The network cards at both ends of the network connection have the highest performance in full-duplex mode, and the network cards on the PC are easily set to half-duplex mode by users unintentionally or intentionally through software. Monitoring the connection speed is very important to find out whether the duplex settings of the two ports match. Experts suggest using a software called Multi-Router Traffic Grapher to monitor the performance of network connections to ensure that full-duplex settings are turned on at both ends.

Using Layer 3 switching

One way to improve network performance is to implement Layer 3 switching on switches connected to desktops. Many switches provide IP routing capability of LAN edge switches and QoS based on Layer 3 switching. With Layer 3 switching, the switch does not send every packet to the router. For example, two nodes in different virtual LANs are connected to the same switch, and Layer 3 edge switches can route communication services between the two nodes.

Increase routing control

This is a configuration called multihoming, which is used to achieve route control or route optimization in sites with multiple Internet connections. The routing control device of the site is connected to the network as BGP (Border Gateway Protocol), which is a routing mechanism to determine which Internet connection to use. This choice depends on which connection requires the least number of router hops to reach the destination. Routing control can choose the best route according to the comprehensive influencing factors of performance and price, which is superior to BGP.

Using group shaping

Packet shapers put network communication services into queues according to their importance, such as critical applications and delay-sensitive applications, which will get higher priority. This can be achieved by limiting the bandwidth occupied by some applications or blocking some applications.

Using compression technology

In order to reduce the number of bytes that need to be transmitted over the WAN, compression devices are installed at sites connected to both ends of the WAN to scan communication services. The principle is to replace the repetitive pattern with a shorter pattern, thus making full use of the limited bandwidth. In addition, by using the acceleration program of SSL layer, the number of bytes of the transmitted web page content can be reduced, and the data unnecessary for rebuilding the web page can be deleted by compression technology to speed up the transmission of SSL on the Internet, and at the same time, the number of TCP connection requests to be processed by the application server can be reduced.

How to improve ADSL internet access speed

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Users often report in forums that ADSL high-speed broadband network is sometimes not as fast as the original narrowband MODEM. So, what is the main reason for the slow internet access? How to quickly find and eliminate? The following article will answer the common problems and solutions of ADSL accessing the Internet.

Too many protocols are bound to the network card.

Internet access is very slow, which is very common among LAN users, because there are too many protocols bound to the network card. If the network card is bound with many protocols, when the data passes through the network card, the computer will spend a lot of time to decide which protocol to use to transmit the data, and then the user will feel slow when surfing the Internet.

Solution:

Let one network card only run PPPOE protocol to connect ADSL, providing external connection to the Internet, and the other network card run other protocols of local area network, thus improving the performance, so that the internet access speed of the client will be improved.

ADSL equipment has poor heat dissipation.

ADSL equipment generates a lot of heat when working, so attention should be paid to heat dissipation at ordinary times. Many users put ADSL equipment, routers and hubs in a cabinet, and all kinds of equipment dissipate heat when working, which has an impact on the normal work of ADSL. If you surf the Internet normally for about 5 minutes, the network speed will drop, and the download rate will be the same as that of a narrow-band 56kMODEM. At this time, touching the equipment by hand is very hot, and changing ADSL equipment will improve the speed.

Solution:

Microcomputer, ADSL and other equipment should not be placed in the same cabinet, but scattered, and there should be ventilation and heat dissipation channels between the equipment. It is best to keep the computer room at a constant temperature, and the general ambient temperature is controlled at 10℃ ~ 30℃. The relative humidity should be kept at 40% ~ 70%.

Error accessing Internet interface.

This is caused by an error in the Internet Connection Wizard of Windows. Enterhet300 (virtual dialing software) uses LAN type virtual dialing, and IE uses ordinary dialing by default. When browsing, IE first looks for the dial-up interface. If you can't find the dial-up, you will find whether there is a proxy server in the LAN, and finally you will find the Enternet300 interface, so it will be very slow.

Solution:

Run the Internet Connection Wizard again, select the LAN mode, and cancel the automatic search for proxy servers.

The system does not support multitasking.

If the user's computer only meets the minimum configuration, the system cannot support multiple tasks such as browsing the web, downloading software and listening to music at the same time. When you handle multiple tasks at the same time, you will feel that surfing the Internet is slow.

Solution:

Users are advised not to do more than two tasks at the same time.

Unbound TCP/IP protocol.

TCP (Transmission Control Protocol) /IP (International Protocol) are not bound, mostly because the network card driver is not installed, the quality of the network card is problematic, and the PCI (bus standard) slot is not good.

Solution:

The network card driver in the device manager should be deleted first, and then installed after restarting; If it still doesn't work, it is recommended to replace the network card with a PCI slot. If it still doesn't work, you can change another network card.

The quality of telephone lines is very poor.

ADSL technology requires high quality telephone lines. At present, ADSL is a kind of RADSL (Rate Adaptive ADSL). If the telephone line between the telephone office and users is disturbed by external factors within a certain period of time, RADSL will dynamically adjust the access speed of users according to the line quality and transmission distance. If you visit a foreign site, the speed will be affected by the export bandwidth, the line and equipment configuration of the other site, and it needs the cooperation of the whole network. The main problems existing in this line are: because the construction standards are not followed during construction, there are hidden quality problems, such as rats biting off the line without plastic casing; Poor jumper contact due to quality problems of distribution frame or other materials; When decorating, the indoor lines hidden by users are damaged.

Solution:

Check whether the line is normal, and you can choose to ask the telecommunications bureau to replace the telephone line.

The software has not been reset.

After installing ADSL broadband, the internet access conditions have changed, but the corresponding tools and software have not been reset, which is one of the reasons for the slow network speed. For example, the communication software QQ, you need to make some settings for it.

Solution:

Select the "System Parameters" command in the QQ panel and click the "Network Settings" tab to change the original "Dial-up Internet Access" to "LAN Access to the Internet".

Microcomputer hardware and software problems

Hardware failure is mainly manifested in the damage or incorrect installation of the user network card; The user's microcomputer motherboard is not compatible with the network card; The user's microcomputer is too low-grade, with insufficient memory and slow running speed. If the hardware is equipped with Celeron 600/64MB memory and WINDOWSXP operating system, it will cause the microcomputer to run quite slowly, and the internet access speed can not be high. Software failure is mainly due to the user's ignorance of computer knowledge and misoperation in the use process, resulting in errors in the operating system or damage to dialing software, which makes it impossible to access the Internet. Incorrect user operation leads to illegal shutdown of dialing software and software error; After the user browsed some web pages, there was a problem in the system, and the backup dialing software was accidentally deleted during the processing; There is something wrong with the user's microcomputer. After reinstalling the system, no dialing software was installed.

Solution:

These problems can be solved by reinstalling dialing software.