In reply to a post by Chrysalis:

yeah I just posted this on the plusnet forum, as aaisp have made a complaint to BTw about latency increases which in my view is down to incompatible devices. As you said g.inp at least on some devices when it wont work falls back to interleaving.

I've just been talking to A&A and given them some information. I hit this issue myself earlier today.

In reply to a post by Zadeks:

My latency went up on the 16th of this month. Is this likely to be due to G.INP or Interleaving?

Modem is ECI. Cab is Huawei.

Graphs:

http://i.imgur.com/JlgjSAD.png
http://i.imgur.com/ZjLYE4A.png

I had exactly same issue on my Huawei Cab with a Huawei modem... I seemed to fix it by updating the firmware to a later version...

While everyone told me it was Interleaving Plusnet where telling me I didn't have interleaving enabled,

Which was correct as BT seemed to of assigned a new Fast Path G.INP profile to my line but the modem didn't recognize it which lead to my slight loss of bandwidth, huge increase in latency and unstable throughput speeds.

Hopefully BT should be soon if not already rolling out updated firmware to all devices that need it.

The cab i'm connected to is a Huawie i recently got interleaved whilst using the supplied ECI modem, for the first 14 days or so, the normal loss of 8-10mps downstream sync and 7-8ms added to base latency , it had happened a few times in the past 2yrs, then at the time that i expected DLM to revert my connection back to fast path it added interleave to the upstream and lowered the ds sync rate a little, as well as adding yet another 7-8ms base latency, so from a 11-12ms base latency i ended up with a 27-28ms base latency
Once this had happened i decided to swap the ECI modem for a huawei that is unlocked , 2 days later the connection went from interleaved to G.Inp latency maybe a little lower as currently is 12-13ms which this modem, would be 13-14ms on fast path , the ECI always had offered a slightly lower latency by around 2ms and upstream throughput again slightly higher (QoS on modem is disabled btw ) So I'm stuck with a supplied locked modem that will now not work until it's fw is updated

Bit tangential to this thread, but how do I find out if my cab is Huawei or ECI? I'm using a Draytek 2760 rather than the BT supplied modem and via Telnet all this can tell me is the DSLAM chip is Broadcom.

It does tell me the VDSL firmware is 05-04-08-00-00-06 if that's any help

Edited by Tacitus (Thu 26-Mar-15 16:33:25)

Which cab/exchange? I can check that way.

In reply to a post by Zadeks:

My latency went up on the 16th of this month. Is this likely to be due to G.INP or Interleaving?

Modem is ECI. Cab is Huawei.

Graphs:

http://i.imgur.com/JlgjSAD.png
http://i.imgur.com/ZjLYE4A.png


Thanks.

If the cab is Huawei then it's likely to be G.INP. Do a tracert; what is your latency like to your 2nd hop?

Also quite a lot of other people have been posting around recently saying G.INP has been enabled on their cabinet.

In reply to a post by WelshWArrior:

Are you sure G.inp is being rolled out nation wide? My fibre was connected yesterday and the Engineer was under the impression that only selected areas were trialing it still.

Yes it is. I also had it enabled on the 22nd and I'm not in a previous trial area.

Edited by chris6273 (Thu 26-Mar-15 16:49:44)

In reply to a post by Tacitus:

...and via Telnet all this can tell me is the DSLAM chip is Broadcom.

I *think* this means it's a Huawei cab.

It looks like interleaving to me. I'm going to guess your modem doesn't support g.inp (at least at your current firmware level), and it looks like the DLM software is putting interleaving on in those cases, for a while at least.

The relevant BT Openreach SIN explicitly states connected modems must support (G.INP � ITU G.998.4). Page 25.

http://www.sinet.bt.com/sinet/SINs/pdf/498v6p0.pdf

Theoretically it is down to ISPs to make sure their customers only connect modems which conform to the SIN. There are other things that might arise in the future, like vectoring, also mandated in the SIN.

Will new firmware be pushed to my ECI modem if it's connected to a Hauwei cab?

I do have a spare unlocked HG612. I just need to locate the latest firmware.

My understanding of it, is that it should be OK with the HG612, the ECI modems *may* need a DLM reset to trigger the firmware upgrade.