Synch Speed

[Justcld]

Hi

I always synched with my exchange at 8128kbps for some reason my synch dropped and it hasnt got back to what it wa s.

I had interleaveing turned on .But requested this off thinking my synch would increase yet if anything its slightly worse i am only able to synch at 7136 kbps surely with interleaveing off i should be synching at 8128kbps

I dont know whether im in 10 day training ,or as i was already on max i do not under go 10 day training

If i am in 10 day training im going to end up with a profile lower than when i first had max due to lower synch speed.

Ive checked and there are no congestion issues at my exchange


Here are line stats

Uptime: 0 days, 0:41:22

Modulation: G.992.1 Annex A

Bandwidth (Up/Down) [kbps/kbps]: 448 / 7,136

Data Transferred (Sent/Received) [MB/MB]: 1.71 / 6.24

Output Power (Up/Down) [dBm]: 11.5 / 11.5

Line Attenuation (Up/Down) [dB]: 5.0 / 11.0

SN Margin (Up/Down) [dB]: 24.0 / 9.5

Vendor ID (Local/Remote): TMMB / µ

Loss of Framing (Local/Remote): 0 / 0

Loss of Signal (Local/Remote): 0 / 0

Loss of Power (Local/Remote): 0 / 0

Loss of Link (Remote): 0

Error Seconds (Local/Remote): 0 / 0

FEC Errors (Up/Down): 0 / 0

CRC Errors (Up/Down): 0 / 0

HEC Errors (Up/Down): 0 / 0

[James]

It looks like BT have set your arget SNR margin to 10. This means tou will sync slighly lower. However, even with that speed, you'd get around a 6500 profile no problem.

It will probably sort itself out in a few days - or you can simply use the DMT tool to set your own SNR thus get it back to 8128.

James

[Justcld]

Thanks James

What would be the ideal snr margin for my line.


I used dmt to get it to 10db ive got the slider to minimum and as dmt drops it by 5db ,it tells me at the moment it's set to 15db. Usually its 12db i heard the bt wholesale guy say to the bt engineer that it should be set at 12db.But it has risen to 15db dslam must have raised it when i had problems

Guess ive just got to be paitent and let things settle then within a couple of works snr margin should drop by 3db shouldnt it

At least England got the win

[Ircsum]

The sequence of events isn't too clear to me from reading the above.

Thr training period does not set your profile - just the MSR & FTR. The profile is something that constantly adjusts with changes in synch.

Both interleaving & a raised target noise margin are used by DLM to help stabilise an unstable line. The higher the target margin the lower the synch, obviously. Interleaving usually takes 0.5 Mbits off the synch.

Using DMT to alter the target margin further confuses the issue (to me, at least). It has been said that, with a raised target margin, a period of stable synch lasting 14 days will result in the target margin being reduced by 3 dB, with further similar reductions for every further 2 weeks of stability. Many have found that this did not happen so I can't be at all certain it's true. Getting BT to reduce the target margin on request is akin to winning the lottery without buying a ticket.

Ircsum.