DSL Interface Statistics

I found this link while troubleshooting a possible DSL issue. Cisco routers support the following command to show DSL interface statistics “show dsl interface atm x/y” where x and y are the port and slot identifiers.

The output of this command will be similar to the following:

Alcatel 20150 chipset information
Modem Status: Showtime (DMTDSL_SHOWTIME)
DSL Mode: ITU G.992.1 (G.DMT)
ITU STD NUM: 0x01 0x1
Vendor ID: ‘ALCB’ ‘ALCB’
Vendor Specific: 0x0000 0x0000
Vendor Country: 0x00 0x0F
Capacity Used: 100% 98%
Noise Margin: 10.0 dB 10.0 dB
Output Power: 20.0 dBm 12.0 dBm
Attenuation: 37.5 dB 23.0 dB
Defect Status: None None
Last Fail Code: None
Selftest Result: 0x00
Subfunction: 0x15
Interrupts: 48337 (0 spurious)
PHY Access Err: 0
Activations: 4
Init FW: embedded
Operation FW: embedded
SW Version: 3.8131
FW Version: 0x1A04

Interleave Fast Interleave Fast
Speed (kbps): 3648 0 832 0
Reed-Solomon EC: 41799 0 11786 0
CRC Errors: 0 0 0 0
Header Errors: 0 0 0 0
Bit Errors: 0 0
BER Valid sec: 0 0
BER Invalid sec: 0 0

The information of most interest is the noise margin, output power, and attenuation as they are the metrics by which line quality is judged. You can also see the current trained DSL speed, downstream is shown first followed by upstream. In this example the downstream speed is 3648 kbps and the upstream is 832 kbps.

The following link covers some good target values for noise margin, output power, and attenuation.