Fully understand the real speed of ADSL

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Fully understand the real speed of ADSL

1. What does 512 k adsl mean?

512 K = 512 kbps = 512 K bits/S = 64 K Bytes/s
I think this conversion should be fine.

2. What does 64 K Bytes/S mean?

The true meaning of this 64 K is "the maximum download bandwidth that individual users can enjoy exclusively"
So what does this mean? I don't know if anyone has noticed the Application Form for installing China Telecom ADSL. The above bandwidth projects are all "no higher than K ", "no higher than 8 m", etc., that is to say, under normal circumstances, we have a maximum of 64 KB of proprietary bandwidth.
Note that the value is "no higher than". That is to say, in many cases, our private bandwidth may be less than 64 KB. Why?
In fact, China Telecom's ADSL is running on the ATM, and the bandwidth from the ATM to the Chinanet edge router is 155 M. Each edge router can connect 3000 users. If these users access the Internet at the same time, in fact, each user only has 50 K bit/s of bandwidth, that is, 7 K Bytes/S. In addition, with the attenuation of the router, the speed of the common Modem may end up.
Of course, the above is just a hypothetical situation. After all, it is almost impossible for 3000 people to connect to an edge router at the same time. China Telecom will not allow the router to be connected at full load, making the speed drop so huge.
However, 64 K is undoubtedly the highest private bandwidth.

3. Why can I download 512 K or more of my k ADSL data?

We figured out that 64 K is the maximum private bandwidth, but not equal to the maximum bandwidth. In fact, when dialing ADSL, we have allocated a download bandwidth of approximately 8 Mbps, that is, 1 M bytes/s, however, China Telecom limits our VPC bandwidth to a maximum of 64 K, so when there are few vro connected users, we can obtain a portion of the shared bandwidth that exceeds the proprietary bandwidth (obviously, telecom does not need to idle the bandwidth ), of course, the K rate of ADSL can never reach the download speed of 1 Mbit/s by occupying the shared bandwidth, because after all, there are still many people surfing the internet at the same time, moreover, China Telecom certainly has some load balancing mechanisms.