Jump in Latency, Much Lower Speeds !!

Seadog · Jul 20, 2011, 17:20:24

Hi All,

Had a sudden slowdown in my FTTC at the weekend Saturday and this seems to have resulted in a slowdown of my Upstream Speed. I have also noticed a general slowdown of the web generally and at the beginning of the week on Speedtest.net was recording very high ping rates from various Servers around 80-90ms. This has now gone back down to around 30'ish however I would like to know how long it takes for my VDSL connection to reset back down to the 12/13ms it normally is?? I trust this was down to Auto DLM and as you can see from below I had some kind of incident which triggered it? Is there anything I can do?? Restarting the Router a 7800N and the VDSL Modem seems to make no difference... My Upstream speed still seems to be stuck at 5 Mb/s which is normally 8.2.

Thanks

pctech · Jul 20, 2011, 17:24:09

Could be local congestion or interleaving may have been introduced by the system if your line was seen to be 'flapping'

Someone with VDSL will be along shortly who can help more I'm sure.

.Griff. · Jul 20, 2011, 17:30:34

It's not congestion but simply the DLM increasing the level of interleaving (you can see the line drop immediately before it re-syncs with interleaving increased).

Unfortunately the DLM on FTTC is completely automated so your IP Profile and level of interleaving cannot be manually amended. I've had 11 months to get used to it

Bill · Jul 20, 2011, 17:31:39

Sounds (and looks) like you've had a period of elevated error rate and the DLM has put you on interleaved... no idea why your upstream has dropped though.

As for reverting to fastpath, don't hold your breath

Seadog · Jul 20, 2011, 17:55:32

Quote from: .Griff. on Jul 20, 2011, 17:30:34
It's not congestion but simply the DLM increasing the level of interleaving (you can see the line drop immediately before it re-syncs with interleaving increased).

Unfortunately the DLM on FTTC is completely automated so your IP Profile and level of interleaving cannot be manually amended. I've had 11 months to get used to it

Thanks Griff and Bill,

Yeh a right pain in the backside, I think that BT have been quite busy putting new FTTC Lines on my local Cab and wondered if this could be the issue, i.e co channel interfererence between lines etc. It would explain a long period of elevated error rate perhaps??? For sure interleaving is on, quite honestly this is not good when I'm only 200M from the Cab, wish I could have FTTP from the Cab!!

Seadog · Jul 20, 2011, 18:19:09

I've just done a quick speedtest and it must be one of the worst results I've got since having FTTC. I can only see things getting worse over the next 12 months as everyone starts getting FTTC around the country, this is a truely awful figure. Maybe time to go back to Be as soon as they get Fibre!!

Glenn · Jul 20, 2011, 18:19:40

Since the problems of 2nd June at Guildford exchange, my connection has been on a 25mb profile, before then, it was at full sync.

Rik · Jul 20, 2011, 18:22:38

I was chatting to a BT management engineer who was responsible for the planning and development of FTTC. He said he wouldn't touch it with a bargepole due to the eventual implementation, which was controlled by the bean counters.

Seadog · Jul 20, 2011, 18:37:46

Quote from: Rik on Jul 20, 2011, 18:22:38
I was chatting to a BT management engineer who was responsible for the planning and development of FTTC. He said he wouldn't touch it with a bargepole due to the eventual implementation, which was controlled by the bean counters.

Yeh, Bean Counters and there is no hope!! Hopefully by the end of my contract in 9 months time Be will have pulled their finger out and have a Fibre product using their network. Mind you even Be has some issues at the moment..

Rik · Jul 20, 2011, 18:42:32

Bill · Jul 20, 2011, 18:48:35

I've got a "keep me updated" link into BE, but I suspect they'll be too expensive with an unlimited product.

100GB or so would do me fine, but "sized" packages don't seem to be BE's thing

Bill · Jul 20, 2011, 19:11:20

Don't think it's associated with Seadog's problem, but something 'orrible happened at about 3o/c:

Even worse in IPv6, in sig if you want to look.

Packet loss is up... profile is unchanged, speed is about normal for this time of evening.

Glenn · Jul 20, 2011, 19:17:16

I'm seeing the same, Bill, and a big drop in download speed

Bill · Jul 20, 2011, 19:20:52

My speed was OK on the BT tester, speedtest.net is not so good:

.Griff. · Jul 20, 2011, 19:29:12

Quote from: Bill on Jul 20, 2011, 19:11:20
Don't think it's associated with Seadog's problem, but something 'orrible happened at about 3o/c:

Here's mine!

Bill · Jul 20, 2011, 19:57:49

Last time I saw spikes like this was when the LONAP link had a problem and IPv6 suddenly started working, stopped after a while then re-started when IDNet changed the peering to LINX... I wonder if Simon/Tim have been playing with routers again?

lozcart · Jul 20, 2011, 20:59:20

It could be all the Mac owners downloading Lion causing the net to grind to a halt, the timing fits the release.

Steve · Jul 20, 2011, 21:03:39

You might not be far wrong there

Edge · Jul 20, 2011, 22:47:07

Mines gone pretty awful too, I thought it was just the DLM doing it's thing as I had BT out yesterday to replace a faulty VDSL modem:

Seadog · Jul 20, 2011, 22:58:35

Quote from: Bill on Jul 20, 2011, 19:11:20
Don't think it's associated with Seadog's problem, but something 'orrible happened at about 3o/c:

Even worse in IPv6, in sig if you want to look.

Packet loss is up... profile is unchanged, speed is about normal for this time of evening.

Evening Everyone,

Yes it's gone horrible again tonight and I note that on Bill and Griff and Edge's Graph there seems to be Packet loss all at the same time around 3pm including me!! I guess something is going on, again...

At this rate my speed will be down to Dial Up by Christmas