ADSL2+ Issues With BT Total Broadband

Hi

I'm having some speed issues with our BT ADSL2+ service. just before Christmas I upgraded our ADSL line t ADSL2+. The line was very flappy for a period. it would sync upto a high speed and after awhile it would resync to a low speed. This is of coure natural. But now it has synced to 1152kbps. I have spoken to BT and they said they have run line tests and they can see that there was frequent line drops, which is why the speed has synced so low. they will run some tests to see if they can see why. They could not see any problems but said that they would monitor it for a period of time.

the other day i was playing with the router and i noticed that it was set to ADSL2+ and not to Auto Detect. So i changed it to auto detect,and it has now synced using ADSL2 and not ADSL2+. So there is a reason for the errors, the router was trying to sync using ASDSL2+ while the exchange was using ADSL2. I have tried relaying this information to BT and no joy. Does anyone know why i have been given an ADSL2 circuit when i should have ADSL2+?

I'm assuming that if i leave my router alone for 10 or so days, the exchange wil gradullay increase the sync speed as there are no errors on the line. is that correct?

I'm using a CISCO877. Below are the line stats for reference..


ATU-R (DS) ATU-C (US)
Modem Status: Showtime (DMTDSL_SHOWTIME)
DSL Mode: ITU G.992.3 (ADSL2) Annex A
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: FCZ114392Q0
Serial Number Far:
Modem VerChip ID: C196 (0)
DFE BOM: DFE3.0 Annex A (1)
Capacity Used: 30% 99%
Noise Margin: 17.5 dB 6.0 dB
Output Power: 16.0 dBm 12.5 dBm
Attenuation: 56.5 dB 32.0 dB
FEC ES Errors: 0 0
ES Errors: 1 0
SES Errors: 1 0
LOSES Errors: 1 1
UES Errors: 0 105
Defect Status: None None
Last Fail Code: None
Watchdog Counter: 0x9F
Watchdog Resets: 0
Selftest Result: 0x00
Subfunction: 0x00
Interrupts: 4191 (0 spurious)
PHY Access Err: 0
Activations: 1
LED Status: ON
LED On Time: 100
LED Off Time: 100
Init FW: init_AMR_4.0.018.bin
Operation FW: AMR-E-4.0.018.bin
FW Source: external
FW Version: 4.0.18

DS Channel1 DS Channel0 US Channel1 US Channel0
Speed (kbps): 0 1152 0 829
Cells: 0 4039393 0 20798237
Reed-Solomon EC: 0 119 0 23
CRC Errors: 0 0 0 32
Header Errors: 0 0 0 7
Total BER: 0E-0 0E-0
Leakage Average BER: 0E-0 0E-0
Interleave Delay: 0 38 0 54
ATU-R (DS) ATU-C (US)
Bitswap: enabled enabled
Bitswap success: 0 0
Bitswap failure: 0 0

LOM Monitoring : Disabled


Any help would be gratefully accepted....


Rgds


Phil

The locking to ADSL2 by you simply speeds up the sync process, i.e. it will not try ADSL2+ before ADSL2

Some hardware goes for the ADSL2+ then fails shortly after due to the noise, and forcing ADSL2 or ADSL can make things more stable. The ISP can force these settings remotely, but BT support and other ISP's are not that aware of the issues.

1152 is too near to the 1Meg fixed profile, to suggest it will not vary, unless the ISP request an unlock.

At 56dB attenuation ADSL2+ will offer you no benefit, ADSL2 will add a little speed in ideal conditions, this is why locking to ADSL2 is better. So you've got an ADSL2+ circuit, but the ADSL2+ signal is attenuated to the point of almost being non existent.

Cisco have released a new firmware for the modem part of the 877

https://supportforums.cisco.com/docs/DOC-6183;jsessi...

if you have the ability to upgrade it to 4.0.0.18, you may have some better luck, but as others have said, might just be easier going on a fixed 1Mb profile

The op is using 4.0.18.

Edited by Rockh (Sat 06-Mar-10 12:45:47)

so he is, my bad

Hi

I have now made a few changes to the router. I have changed the firmware to 3.0.033 and set the router to autodect ADSL. I'm now getting 3.5Mb.

Alcatel 20190 chipset information
ATU-R (DS) ATU-C (US)
Modem Status: Showtime (DMTDSL_SHOWTIME)
DSL Mode: ITU G.992.3 (ADSL2) Annex A
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: FCZ114392Q0
Serial Number Far:
Modem VerChip ID: C196 (0)
DFE BOM: DFE3.0 Annex A (1)
Capacity Used: 92% 99%
Noise Margin: 3.0 dB 6.0 dB
Output Power: 18.0 dBm 12.5 dBm
Attenuation: 55.5 dB 32.0 dB
FEC ES Errors: 0 0
ES Errors: 0 0
SES Errors: 0 0
LOSES Errors: 0 1
UES Errors: 0 177
Defect Status: None None
Last Fail Code: None
Watchdog Counter: 0x1F
Watchdog Resets: 0
Selftest Result: 0x00
Subfunction: 0x00
Interrupts: 8239 (0 spurious)
PHY Access Err: 0
Activations: 1
LED Status: ON
LED On Time: 100
LED Off Time: 100
Init FW: init_3.0.33_nobist.bin
Operation FW: AMR-3.0.033.bin
FW Source: external
FW Version: 3.0.33

DS Channel1 DS Channel0 US Channel1 US Channel0
Speed (kbps): 0 3544 0 798
Cells: 0 5152888 0 29437876
Reed-Solomon EC: 0 43014 0 0
CRC Errors: 0 695 0 32
Header Errors: 0 467 0 11
Total BER: 0E-0 65535E-255
Leakage Average BER: 0E-0 65535E-255
Interleave Delay: 0 62 0 58
ATU-R (DS) ATU-C (US)
Bitswap: enabled enabled
Bitswap success: 0 0
Bitswap failure: 0 0