ADSL2 vs ADSL2+ (ADSL2 Plus)
ADSL(Asymmetric Digital Subscriber Line) is a fixed line broadband technology, it is a form of DSL. ADSL offers high speed access over the same existing copper network in parallel with telephone line. Asymmetric means the download bandwidth and upload bandwidth are not the same in ADSL. It was designed by considering human activity on internet. Mostly people use more downloads than uploads in Internet. ADSL speeds vary from 1 Mbps to 20 Mbps depends on various parameters including the distance of the user from the DSLAM (Digital Subscriber Line Access Multiplexer, which is a hardware that connects all the DSL users) and the line conditions.
ADSL2(ADSL2附件A)
ADSL2是ADSL的一种形式,其带宽比ADSL更多。ADSL2被称为ADSL2附件A或Just ADSL2。由于改进的调制技术,ADSL2提供了约12 Mbps下载带宽和1 Mbps上传带宽。ADSL2初始化的速度更快,大约需要3秒,然后快速连接。
ADSL2 supports channelization thus by allocating 64kbps channels of ADSL2, we can transport digital voice signal directly via DSL by using PCM modulation. Service providers can offer voice and data solution via ADSL2.
ADSL2+ (ADSL2 Plus)
ADSL2+ is the next generation ADSL technology to offer high bandwidth using the same copper lines.ADSL2+ can offer up to 24 Mbps but which depends on many parameters. ADSL2+ was introduced in 2003 and it’s an ITU standard g992.5.
ADSL2+ uses twice the frequency band of ADSL2 (2.2MHz) thus download data rates is possible around 24 Mbps. ADSL2+ upload speed remains as 1Mbps.
In short, ADSL2+ is better than ADSL2 in access speed but which doesn’t mean you can browse internet faster in ADSL2+ than ADSL2. There are many other parameters which influences the speed or throughput.
简介:
ADSL2最多可提供12 Mbps,ADSL2+可以提供理论上24 Mbps。但是所有人都应该了解速度,带宽和吞吐量之间的区别。我们谈论的所有速度12m,24m,2m基本上都是线速度,或者您可以说访问速度。这不能保证您可以以这种速度访问互联网。
ADSLis an access technology to provide a broadband connection to you from the service providers systems. Even though you have 24 Mbps ADSL2+ at your end, service provider will not connect you to internet backbone at the same speed. They have a ratio called contention ratio, which simply we can say, 100 ADSL2+ (24 Mbps) customers will be connected via 24 Mbps internet backbone. So backbone internet connection will be shared among 100 customers if all 100 customers are using the internet at the same time. This is a general theory and differs from country to country. In Some countries they don’t apply contention ratio instead their packages are sized like 20 GB per month and may be mixture of both.
GenerallyADSL,ADSL2和ADSL2+(ADSL2 Plus)速度取决于以下:
(1)距电话交换的距离(ADSL2+从24 Mbps开始,距交易所的距离为5.5 km的25 Mbps,ADSL本身将提供)
(2) Line Condition of your copper connection
(3) Line Profile offered to you by the Service Provider (Service providers have different line profile for different packages)
(4)外部电动干扰铜对
(5)服务提供商在骨干方面的互联网带宽
(6)目标服务器的带宽和性能。(例如:当您访问www.yahoo.com时,托管www.yahoo.com的服务器以及连接带宽以及带宽的用法和服务器性能也会影响您的吞吐量)
One main concept, I would like to explain here, assume ADSL2 and ADSL2+ are like 20 lanes highway which does not mean you can fly. You can drive in 120 Km/hr in a 6 lanes road as well. At the same time you can only drive 120 on the 20 lanes road also. So what’s the difference?
以上是正确的,但是在20号车道中,您可以以120 km/hr的速度驾驶20辆车,而在6号车道中,您只能以120 km/hr的速度驾驶6辆车。因此,当您在计算机上使用多个应用程序时,只能感觉到ADSL2或ADSL2+的速度差异。用技术术语来说,您需要创建多个TCP,UDP会话(例如:下载带有加速器的文件比通过单个FTP下载或正常下载要快的速度)。
ADSL2和ADSL2+(ADSL2 Plus)之间的差异,快速回顾: (1)ADSL2和ADSL2+是提供高速互联网访问的类似宽带访问技术。 (2) ADSL2 can offer max up to 12 Mbps whereas ADSL2+ can go up to 24 Mbps. (3) For both ADSL2 and ADSL2+ , Wi-Fi routers can be used. (4) ADSL2+ routers come with built-in Wi-Fi and VoIP. (5) ADSL2+ is the best access technology over copper lines at the moment. |
shahzad ali说
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abubaker说
Mode:
ADSL2+
Type:
Interleave
行编码:
格子上
Status:
No Defect
链路电源状态:
L0
Downstream
Upstream
SNR Margin (dB):
7.6
6.3
衰减(DB):
47.5
25.8
输出功率(DBM):
19.3
12.6
Attainable Rate (Kbps):
6120
522
Rate (Kbps):
2557
522
MSGc (number of bytes in overhead channel message):
64
12
b(MUX数据框中的字节数):
14
11
M(FEC数据框中的MUX数据帧数):
1
16
T (Mux Data Frames over sync bytes):
5
5
R (number of check bytes in FEC Data Frame):
14
16
S (ratio of FEC over PMD Data Frame length):
0.1852
11.5556
L (number of bits in PMD Data Frame):
1253
144
D (interleaver depth):
320
2
Delay (msec):
14
5
超级框架:
25443
25694
Super Frame Errors:
2679
10262669
RS Words:
8905320
142245
RS Correctable Errors:
128203
16722528
RS不正确的错误:
795088
N/A
HEC错误:
504
25716975
强迫症错误:
399
0
LCD Errors:
2
0
Total Cells:
2259805
3918919984
Data Cells:
660077
1028780556
Bit Errors:
0
1147195294
Total ES:
16774
2142220
Total SES:
75
255246
Total UAS:
1722
17993833