Broadband speed / line stats - advice from useful people needed

growse · 24 Feb 2011 at 20:59

I've just had the broadband (AAISP) activated at my new house, and it's been a while since I dug into what the line stats mean for speeds.

The line is a 21CN line with Annex M enabled on it. Stats off the router are as follows:

Code:

talkbot#sh dsl interface  atm0
ATM0
Alcatel 20190 chipset information
                ATU-R (DS)                      ATU-C (US)
Modem Status:    Showtime (DMTDSL_SHOWTIME)
DSL Mode:        ITU G.992.5 (ADSL2+) Annex M
ITU STD NUM:     0x03                            0x2
Chip Vendor ID:  'STMI'                          'IFTN'
Chip Vendor Specific:  0x0000                    0x71B9
Chip Vendor Country:   0x0F                      0xB5
Modem Vendor ID: 'CSCO'                          '    '
Modem Vendor Specific: 0x0000                    0x0000
Modem Vendor Country:  0xB5                      0x00
Serial Number Near:    FCZ123464EX
Serial Number Far:
Modem VerChip ID:        C196 (3) capability-enabled
DFE BOM:         DFE3.0 Annex M (3)
Capacity Used:   99%                             100%
Noise Margin:     4.5 dB                          6.0 dB
Output Power:    19.5 dBm                        12.5 dBm
Attenuation:     42.5 dB                         19.0 dB
FEC ES Errors:    0                               0
ES Errors:        1                               0
SES Errors:       1                               0
LOSES Errors:     1                               0
UES Errors:       0                              171
Defect Status:   None                            None


                DS Channel1      DS Channel0   US Channel1       US Channel0
Speed (kbps):             0             3399             0              2308

So I'm getting a decent U/L speed, but downstream is a bit disappointing, was expecting more like 6Mbit given the distance (1km).

I also know that this has just been activated, so might fluctuate over the next few days. Do the line stats look reasonable, or dodgy?

Locky · 24 Feb 2011 at 21:04

You are on Annex M 2.5mb upload, this is killing your download. you need to get your isp to turn it off.

even 3.4mb on a 42db line is poor, I would check the house wiring.

lemzip · 24 Feb 2011 at 21:07

Line looks okay, low on the downstream but you running annex m which uses downstream tones to help with the upstream and due to your attenuation, you dont have much snr anyway.

What router do you have? If you can force modes, try normal ADSL2+ (G.992.5) and you will see you should get over 6-8mbit but your upstream will be around 1200kbps (depending on isp)

growse · 24 Feb 2011 at 22:02

Thanks for the responses, I'm on a Cisco 877. I'll try and get Annex-M disabled, I requested it from the ISP as I had it on my old Be line. That said, I had 14Mbit down on the Be line...

lemzip · 24 Feb 2011 at 23:31

with that attenuation 14mbit is impossible im afraid.

Did you mean on another line?

growse · 25 Feb 2011 at 17:58

lemzip said:
with that attenuation 14mbit is impossible im afraid.

Did you mean on another line?

Sorry, yes, my previous line (previous address) was 14Mbit, and that was with Annex-M turned on. I guess with a worse quality line, I'll have to live with a lower upload if I want decent downstream.

lemzip · 25 Feb 2011 at 18:18

yep.

Can you not force modes on your router? I can force different modes if i want however Annex-M is not available with my isp.

At least you can then swop modes when you want a higher upload speed and then back to ADSL2+ when you want download speed.