As kasg says. Plus.

You clearly have an unlocked modem. (Unless you are using 3rd-party kit).

With an unlocked modem you need to run xdslcmd info --pbParams. I think "Max" will be what would be possible after the Discovery phase. The sync is what results from the Medley phase, where certain tones have been dropped for whatever reason.

The "Max" will vary second by second following the sync, because of noise conditions changing, in the same way as noise margin does.

Edited by RobertoS (Fri 20-Dec-13 13:18:55)

In reply to a post by timh:

So what exactly is 'Max' connection speed, I thought this was your actual sync speed and the profiles would be set at the profile closest to this ?

I hope kasg and myself have dealt with the Max figure.

IP Profile is a BT Wholesale thing, nothing whatsoever to do with the line stats. It is derived directly from the sync and on FTTC is 0.9769 of the sync. Note that LLU providers, as on ADSLx, do not have IP Profiles. But on FTTC they (used to) have the same Openreach modem.

BT Wholesale limits the delivery speed from its network to the DSLAM to the IP Profile value.

In reply to a post by RobertoS:

In reply to a post by timh:

So what exactly is 'Max' connection speed, I thought this was your actual sync speed and the profiles would be set at the profile closest to this ?

I hope kasg and myself have dealt with the Max figure.

IP Profile is a BT Wholesale thing, nothing whatsoever to do with the line stats. It is derived directly from the sync and on FTTC is 0.9769 of the sync. Note that LLU providers, as on ADSLx, do not have IP Profiles. But on FTTC they (used to) have the same Openreach modem.

BT Wholesale limits the delivery speed from its network to the DSLAM to the IP Profile value.

Yes - thanks for your replies, its a little clearer now. Obviously the question would now be is there anything I can do from my end to get my downstream sync back closer to the 'max' figure (upstream is already very close)? My line although around 1km, seems reasonably quiet (looking at the SNR/Errors etc).

In reply to a post by kasg:

In reply to a post by timh:

So what exactly is 'Max' connection speed, I thought this was your actual sync speed and the profiles would be set at the profile closest to this ?

No, "Path" is the actual sync speed, "Max" is a theoretical maximum and can be ignored for most purposes.

Also, once the modem's firmware has been remotely updated, "Path:" changes to "Bearer":-

Max: Upstream rate = 4946 Kbps, Downstream rate = 22496 Kbps
Bearer: 0, Upstream rate = 4928 Kbps, Downstream rate = 20488 Kbps

FWIW, I have a 3rd party modem/router will full access to stats. In the 18 months that I have had FTTC my max attainable downstream has fallen from 102 to 92Mbps (crosstalk as take up has increased). My modem is about 300 M from the cabinet and my connection normally runs on a FastPath. From time-to-time, some external disturbance will cause the DLM to do its thing. This is the case at the moment. Currently, the DLM has imposed a latency figure of 8 ms and Impulse Noise Protection of 3 on the downstream side of my connection. The overall result is a reduction in downstream speed of about 8Mbps. As my Max Attainable speed is above 80Mbps then my IP profile remains unchanged. The GUI is showing no errors ES, MES or CRCs since this change therefore I expect that the DLM will turn off interleaving at some point in the future. Past experience is that this will take about 3 weeks.

Of interest (maybe), the latest firmware upgrade to the Fritz!Box serious of boxes has removed all FEC counts (presumably as they have concluded that they are in themselves pretty meaningless) and brought in G.Vectoring Ready. Not bad for a 3 year old box (in my case) with 2 years of the warranty to run.