Useful Information

DSL Technologies

ADSL

Asymmetric Digital Subscriber Line

ITU G.992.1 – G.DMT – 8.0Mbit/s, 1.0Mbit/s

ITU G.992.2 – G.Lite – 1.5Mbit/s, 0.5Mbit/s

ITU G.992.3/4 – ADSL2 – 12Mbit/s, 1.0Mbit/s

ITU G.992.5 – ADSL2+ – 24Mbit/s, 1.0Mbit/s

SDSL

Symmetric Digital Subscriber Line

SHDSL

Symmetric high-speed digital subscriber line

ITU G.991

VDSL

Very high bit-rate Digital Subscriber Line

ITU G.993.1 – VDSL

ITU-T G.993.2 – VDSL2

Signal Level Guide

ADSL

Downstream SNR = 15 dB.

Higher is better, minimum = 6 dB.

Downstream Power = < 15 dBm.

Lower is better.

Upstream SNR = 10 dB.

Higher is better.

Upstream Power = < 15 dBm.

Lower is better.

Downstream Attenuation = < 30 dB

Lower is better, maximum = 60 dB.

Upstream Attenuation = < 30 dB

Lower is better, maximum = 60 dB.

ADSL2+

Downstream SNR = 06 dB.

Higher is not better. Within range is better = 05 – 07 dB.

Downstream Power = < xx dBm.

Lower is better.

Upstream SNR = 06 dB.

Higher is not better. Within range is better = 05 – 07 dB.

Upstream Power = < xx dBm.

Lower is better.

Downstream Attenuation = < 22 dB

Lower is better, maximum = 22 dB (for 10mbps), 12 dB (for ~25mbps).

Upstream Attenuation = < 22 dB

Lower is better, maximum = 22 dB (for 10mbps), 12 dB (for ~25mbps).

Attenuation to Loop Length Conversion

10 dB ~ 0500 m

15 dB ~ 1000 m

25 dB ~ 2000 m

35 dB ~ 2500 m

NOTE

All readings are based on CPE, with average error margin of CPE taken into considerations.