17a DSLAM Update

Does anyone know what form this update takes? I.E Is it a firmware update?

Dunno - might be no more than some SNMP to set the profile.

To the end-user modems, or to the cabinets?

I don't think there is anything needed at all within the modems: they are already capable of the 17MHz frequencies and the new 9098 bandplan - and they just get given the setup during negotiation with the cabinet.

No idea about the cabinets themselves though. The changes involve an update to the way the frequencies are used, as well as the top-end frequency, and the power levels for the transmitter. They will also require new "power mask" settings, to ensure the VDSL signals don't interfere with the existing ADSL/ADSL2+ subscribers.

The Ofcom document that allows this is called the ANFP, and that seems to describe these things in terms of a MIB - which suggests that the cabinets are already capable of the 17a profile, and just need configuring using some SNMP O&M commands.

My cabinet seemed to change around 2AM on a Monday morning, so I guess it isn't a manual visit

In reply to a post by WWWombat:

To the end-user modems, or to the cabinets?

I don't think there is anything needed at all within the modems: they are already capable of the 17MHz frequencies and the new 9098 bandplan - and they just get given the setup during negotiation with the cabinet.

No idea about the cabinets themselves though. The changes involve an update to the way the frequencies are used, as well as the top-end frequency, and the power levels for the transmitter. They will also require new "power mask" settings, to ensure the VDSL signals don't interfere with the existing ADSL/ADSL2+ subscribers.

The Ofcom document that allows this is called the ANFP, and that seems to describe these things in terms of a MIB - which suggests that the cabinets are already capable of the 17a profile, and just need configuring using some SNMP O&M commands.

My cabinet seemed to change around 2AM on a Monday morning, so I guess it isn't a manual visit

I was referring to the actual DSLAM's themselves (Obviously inside the cabinets)

The reason I ask is I've been experiencing an ongoing problem of CRC/HEC errors (1 million+ every 24 hours) and some packet loss all day long (as indicated on my TBBQM) for months. Openreach have attended multiple times, acknowledged the existance of the errors but no-one ever found the cause and I resigned myself to putting up with it.

HOWEVER as of this morning I'm on 17a and the errors are no longer occurring and the packet loss has vanished. It's either one hell of a coincidence or whatever the 8c > 17a process involves has fixed my issues.

Edited by griff_90 (Thu 10-Nov-11 15:58:45)

In reply to a post by griff_90:

I was referring to the actual DSLAM's themselves (Obviously inside the cabinets)

The reason I ask is I've been experiencing an ongoing problem of CRC/HEC errors (1 million+ every 24 hours) and some packet loss all day long (as indicated on my TBBQM) for months. Openreach have attended multiple times, acknowledged the existance of the errors but no-one ever found the cause and I resigned myself to putting up with it.

HOWEVER as of this morning I'm on 17a and the errors are no longer occurring and the packet loss has vanished. It's either one hell of a coincidence or whatever the 8c > 17a process involves has fixed my issues.

Hi griff_90,

It seems the opposite way round for me.

Since the 17a profile switch I have been seeing in excess of 1 Million CRC errors within a 24 hour period.

I have an engineer's visit booked for Tuesday 15th.

Hopefully, a physical fault will be found & repaired & I will get my previous higher speeds back.

If anything, they should be even better now, looking at other posts where users have confirmed downstream improvements at the expense of a slight loss up upstream speeds.

Paul.

In reply to a post by griff_90:

The reason I ask is I've been experiencing an ongoing problem of CRC/HEC errors (1 million+ every 24 hours) and some packet loss all day long (as indicated on my TBBQM) for months. Openreach have attended multiple times, acknowledged the existance of the errors but no-one ever found the cause and I resigned myself to putting up with it.

HOWEVER as of this morning I'm on 17a and the errors are no longer occurring and the packet loss has vanished. It's either one hell of a coincidence or whatever the 8c > 17a process involves has fixed my issues.

Ironic... I suffered 4% packet loss 24/7 during the first 2 days of my FTTC subscription. Then DLM added interleaving (with a visible jump in latency on the BQM) and reduced speed by 4Mbps (according to the IP profile) - which killed off the packet loss entirely.

I then regraded to a 10Mbps upstream, which restored DLM to the initial setting, and I went through the same thing for another 2 days, before DLM intervened a second time (with the same results).

The 17a profile has allowed my line to run without interleaving, and has put the profile back up to 38716 (1 shy of the max).

No idea about error rates, as I haven't unlocked the modem yet.