lilian2005

我付A** 5M的上网费，可是Bell只给了1M的上限，虽然不影响看电影，但是感觉还速度高了更好。请问这种情况怎么办？谢谢。

coala

adsl速度跟你家里机房的距离有关。

http://www.telcodata.us/telcodata/telco?npa=514

输入局号，即514后面的三位数字，dryloop用户可以用邻居的号码，然后点击detailed switch info

之后出现的地图里标示了CO的位置，然后googlemaps就可以帮助你算出你到CO的距离了。

一般住downtown的话，不会超过三五公里，我觉得1M是低了点，如果能够查到一些线路的指标，应该可以有针对性地提高。

coala

即便距离差不多，同一栋大楼里，dsl线路也会参差不齐。

服务好的ISP，会帮你分析线路参数，帮助你改善和调整。

尤其以下面俩个参数重要，

Line Attenuation

SN Margin

研究一下还是很有必要的。



example:

Link Information




Uptime:0 days, 21:03:47
Modulation:G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]:800 / 4.032
Data Transferred (Sent/Received) [MB/GB]:327,58 / 1,52
Output Power (Up/Down) [dBm]:11,5 / 19,0
Line Attenuation (Up/Down) [dB]:31,5 / 57,0
SN Margin (Up/Down) [dB]:9,0 / 6,0
Vendor ID (Local/Remote):TMMB / ALCB
Loss of Framing (Local/Remote):0 / 0
Loss of Signal (Local/Remote):1 / 0
Loss of Power (Local/Remote):0 / 0
Loss of Link (Remote):0
Error Seconds (Local/Remote):116 / 0
FEC Errors (Up/Down):0 / 0
CRC Errors (Up/Down):0 / 3.087
HEC Errors (Up/Down):0 / 2.609


Additional Information
SN Margin (AKA Signal to Noise Margin or Signal to Noise Ratio) Relative strength of the DSL signal to Noise ratio: 6dB is the lowest dB manufactures specify for modem to be able to synch. In some instances interleaving can help raise the noise margin to an acceptable level. The higher the number the better for this measurement.
6dB or below is bad and will experience no synch or intermittent synch problems
7dB-10dB is fair but does not leave much room for variances in conditions
11dB-20dB is good with no synch problems
20dB-28dB is excellent
29dB or above is outstanding
Line Attenuation
Measure of how much the signal has degraded between the DSLAM and the modem: maximum signal loss recommendation is usually about 60dB. The lower the dB the better for this measurement.
20dB and below is outstanding
20dB-30dB is excellent
30dB-40dB is very good
40dB-50dB is good
50dB-60dB is poor and may experience connectivity issues
60dB or above is bad and will experience connectivity issues


关于线路数据，我的speedtouch modem是直接可以显示的，那之前我用speedstream modem，我也曾查看过线路状态，具体的软件名称是DMT

http://dmt.mhilfe.de/

是不是普适于所有的modem，我不知道，最好查一下，你的modem型号，以及别人的使用经验，据说不是DMT的版本越高越好，当时我看到的说明是只能用版本7的。

该软件是德文的，所以请自行google英文的使用说明先。