Users who often use ADSL, do you know the true speed of ADSL? With this question we will expand the problem step by step. Many users report that the ADSL download rate does not reach the nominal 5 12K. After accessing the network through ADSL, a download rate indicator bar will appear when downloading. The download rate shown above is generally about 50KByte/s! This is actually a misunderstanding caused by an unclear conversion relationship. What does 1,512KADSL mean? 512K=512Kbps=512Kbits/s=64Kbytes/s I think there should be no problem with this conversion. What does 2,64Kbytes/s mean? The true meaning of this 64K is "the maximum download bandwidth that individual users can enjoy." So what does this mean? I don't know if anyone has noticed the application form for telecom ADSL installation. The above bandwidth items are written. Not higher than 512K", "not higher than 8M", etc., which means that we can have a proprietary bandwidth of up to 64K under normal circumstances. Note that it is "not higher than", that is, many times Our proprietary bandwidth may be less than 64K, so why? In fact, China Telecom's ADSL is running on ATM, ATM to chinanet edge router bandwidth is 155M, each edge router can connect 3000 users, if these users At the same time, the Internet, then each user actually only 50kbit /s bandwidth, which is 7Kbytes /s, plus router attenuation, then the final may only have the speed of the ordinary modem. Of course, the above is only a hypothetical situation, after all, 3,000 people are connected at the same time It’s almost impossible to have a router on the edge of the router. Telecom will not overload the router. Connections make the speed drop so huge. However, 64K is the highest proprietary bandwidth is undoubted. 3, then why can my 512KADSL often reach the download speed of 100K or even more than 200K? We figure out that 64K is the most proprietary Bandwidth, but not equal to the maximum bandwidth, in fact, when ADSL dial-up has been allocated, it is actually equal to 8Mbps, which is 1Mbytes/s of download bandwidth, but telecom limits our proprietary bandwidth up to 64K, then when the router is connected In less time, we can get a share of the shared bandwidth beyond the proprietary bandwidth (obviously it is not necessary for the telecom to idle these bandwidths), of course, 512K ADSL can never reach the download speed of 1M/s by occupying the shared bandwidth, because after all There are still a lot of people surfing the Internet at the same time, and there must be some mechanism for balancing the load. 4. The impact of ADSL upload speed on downloading? TCP/IP stipulates that every packet needs to be returned with an acknowledge message. , the transmission of information, need to have a The reply to the data message can determine the subsequent transmission speed and decide whether to retransmit the lost data. Part of the upstream bandwidth is used to transmit these acknowledgement data. When the uplink load is too large, it will affect the acknowledgement. The transmission speed of the data, and thus the download speed. This affects the asymmetric digital loop, which is the ADSL uplink bandwidth much smaller than the download bandwidth. It has been proved that when the upload is full, the download speed is It becomes 40% of the ideal speed, which explains why many friends use BT to download a slightly faster speed limit instead of a faster download speed. In this case, we can't ask all people to be unlimited, because it is unrealistic and unscientific for ADSL users. The proper speed limit is correct. 5. The speed of ADSL gradually decreases as the connection time increases. As I said before, ADSL will establish the highest theoretical 8Mbps download bandwidth when dialing again. This bandwidth will never change! However, in fact, due to the noise detection mechanism of ADSL, if the line condition is not good, the connection established at the beginning is obviously impossible to reach the theoretical value, and may be 5 Mbps at the end, and this bandwidth will not change. Then why is the speed of ADSL slower and slower? This is because even if the user does not turn off the power of the modem, sometimes the ADSL link will be interrupted at any time. For example, in the case where the communication state is deteriorated due to an increase in noise, and an error frequently occurs. Once the link is broken, it will be re-commissioned and the link will be re-determined. However, if the noise that caused the link to break at this time still exists (this is generally relatively large), the speed after re-linking will be lower than the original. Since the link speed determined in the debug is also fixed, the link speed does not increase even after the noise disappears. The longer the ADSL modem is used, the higher the probability of this happening, so the connection speed is getting slower and slower. At this point, if the user restarts the modem, the link is re-established and the speed may be increased. This common sense can be used as a countermeasure after the link speed is reduced. Of course, the above mentioned cases are only discussed according to the ADSL connection itself, and the actual situation includes the Internet status, the response of the website itself, and the like. With the above knowledge, you may be suddenly clear. The original 512K is not 512KB, only 64KB, 呜呜~~~ you can not reach the download speed of 512KB per second. Realizing the high speed of ADSL The most important thing to pay attention to when solving ADSL speed is that the user host must reach a certain configuration to ensure the speed of ADSL access on the hardware. As the saying goes, "There is no diamond, no porcelain," if the processing power of the personal computer is high, you can quickly run the web browser and mail software to improve the speed of the Internet. If you install 1Mbps ADSL, but your personal computer can only install Windows95 or 98, of course, you will feel slow. Especially if the memory is only 64MB or 128MB, broadband is like a hero's useless. If you update your PC and the operating system can use Windows XP, the speed of natural broadband access will increase. In addition, Windows XP requires more memory than the original Windows system, and it is recommended to have at least 256MB of memory. If you don't have the ability to update your PC, increase the memory and you'll feel the speed increase as you increase the memory. In addition, the ADSL modem used for broadband access also supports high speed to ensure access speed. There are also some methods for maintaining ADSL on the hardware, such as minimizing the telephone line between the telephone socket and the ADSL modem, which can minimize the line loss. Specifically, the distance between the telephone socket and the ADSL modem can be shortened, and the connection modem can be lengthened. With the network cable of the personal computer, it will not slow down. Also, do not place office equipment (including personal computers) that emit electromagnetic waves near ADSL modems, or home appliances and mobile phones such as TVs and refrigerators, which will cause interference to the modem. Anyone familiar with the computer should know that the performance of the personal computer depends not only on its own hardware foundation, but also on the software optimization of the computer in the later stage. On the one hand, the performance of the system itself can be improved by some of the more "flooding" system optimization software, CPU vacancy rate, memory usage, hard disk fragmentation, etc., can be improved by the power of software. On the other hand, when broadband access is connected to the network, some special software can also be used for optimization, and some network connection settings are randomly adjusted to achieve the best connection effect.