Terrible performance Leicester (LE3) - Page 8

Ignitionnet · 15-12-2010, 12:59

Quote:

Originally Posted by qasdfdsaq

That's interesting because I seem to have observed VM's network/equipment appear to have two operating "modes" - one with low latency, high speeds, and considerable packet loss just as you describe, and the other one with moderate latency, moderate speeds, and zero packet loss.

The different hardware does handle congestion differently.

CMTS can respond to upstream congestion in one of two ways, they can either ignore the excess requests and force the modems to re-request and they drop traffic, or they can give them zero-length grants which tell them to wait and buffer the data they have to transmit.

The first scheme causes packet loss and a touch of jitter, the second latency and considerable jitter.

The first scheme can be overcome to an extent by transport level protocols so download speeds aren't necessary too badly affected, the second not so much.

Chrysalis · 15-12-2010, 16:44

ignition you remember the time i reported to you changing behaviour? I had the odd day where latency would drop to very low levels but then the next day it would revert, so I agree with him I think VM seem to be able to change between different modes as I dont think I was switched to different kit just for one day here and there.

when latency was low (along with low speeds but not extremely low) overall the connection was better, most things felt snappier and ssh was fine to use. Only bulk downloading lost out. This was at the time i was able to always get full speed when jitter was high (before nov)

Ignitionnet · 15-12-2010, 17:20

Nah SSH feels nasty with packet loss, that would have been something else, some load variation or congestion on downstream more than upstream.

Accompanying the low latency is packet loss, most things wouldn't feel snappier, SSH would suck, browsing feel nasty but bulk downloading would feel be better.

Interactive protocols suck mightily regardless of the queueing system when upstream is sufficiently congested.

Chrysalis · 15-12-2010, 18:02

thats true, whilst I did have packet loss that day it wasnt continous.

qasdfdsaq · 15-12-2010, 22:26

Thanks for the explanation Ignitionnet, that certainly does seem to explain what's going on. Interestingly though, this was 9am on a Monday morning, right after they'd done capacity upgrades, so curious that upstream congestion was sufficient to cause ~10% packet loss.

That said they might have still been in the middle of said upgrades at the time... Either way my upstream speed has now doubled (1.3Mb instead of 0.5-0.7) at peak time; slow progress but progress none the less...

Chrysalis · 17-12-2010, 18:44

things were improved both wed and thurs and was even using VM on my laptop. today is very bad again tho.

gondalio · 17-12-2010, 19:55

Leicester have been having some insane issues with their bb service, everytime i went to a bb job in leicester, 9/10 of them had to be reffered back to network. their network was in shambles for quite sometime but was told that they should all be getting upgraded. not sure if much has been done but if it hasnt been fixed yet you could still be waiting

Chrysalis · 17-12-2010, 19:58

Quote:

Originally Posted by gondalio

Leicester have been having some insane issues with their bb service, everytime i went to a bb job in leicester, 9/10 of them had to be reffered back to network. their network was in shambles for quite sometime but was told that they should all be getting upgraded. not sure if much has been done but if it hasnt been fixed yet you could still be waiting

nice to see some honest feedback from staff on here. I appreciate your post.

gondalio · 17-12-2010, 20:05

yeh i worked in leicester for a few weeks and jeeez was there broadband issues or what, specially in the city center, a lot of students having plenty of issues with the bb. modem config pages were fine but just couldnt understand why people were getting intermittent speeds and connectivity. like i said though, at the time i was told that the issue was in hand and being dealt with but talking to my mate over there, there still seems to be some problems. now when they upgrade the network for the new upload speeds and 100mb, im not sure whether that might sort it out because the UBR's are getting re-arranged to accomadate the new 100mb and dedicated tivo modem.

Chrysalis · 17-12-2010, 21:10

yeah possibly meaning channels be lost for these new services, can only speculate as its all hush hush.

I cant even get a fault number for my issue, I have asked the CEO office 4 times for it, and the VM forums 3 times, and get inconsistent replies.

eg. I was told some weeks ago now a new reseg is forthcoming and then eventually got told the spring 2011 date. If there is a date I would assume thereis a reference number so I have since asked for this reference number.

I then asked again on the VM forums and was told they raising it to the network team, which indicates there is no existing upgrade planned. They of course also wouldnt give me a reference number yet other customers get one, lots of weirdness about my area.

gondalio · 17-12-2010, 21:35

what reference number are you reffering to?

Chrysalis · 17-12-2010, 21:46

when people report faults they get a reference number that starts with F0.

gondalio · 17-12-2010, 21:57

they must of ran out lol joke... Im not sure to be honest with you, only thing i can suggest is persist with the issue and dont sit and wait. I will speak to my mate tomorrow and see if he knows anything about whats going on over there. the network guys tend to know what the crack is across all areas lol dont hold your breathe on me though... but ill do what i can

pip08456 · 17-12-2010, 22:04

Quote:

Originally Posted by qasdfdsaq

Fault reference I assume

Correct.

Chrysalis · 17-12-2010, 22:21

Quote:

Originally Posted by gondalio

they must of ran out lol joke... Im not sure to be honest with you, only thing i can suggest is persist with the issue and dont sit and wait. I will speak to my mate tomorrow and see if he knows anything about whats going on over there. the network guys tend to know what the crack is across all areas lol dont hold your breathe on me though... but ill do what i can

I gave up now, but one thing is a complete lack of proffesionalism from VM on this. The service has been unuseable for long periods of the day in the past week or 2 and most other isp's performing this bad would treat it as a matter of urgency.

The recent query on the VM forums was just to see if I got consistent information to match what I been told by the CEO office, it wasnt.

Rose on the VM forums perhaps said too much for staff and confirmed some overloaded ports are due to "too many modems".

I even read today someone's port upgrade got cancelled simply because the utilisation has temporarily dropped again, no doubt he will be reraising his fault when it increases again. This made me think about how leics has got so bad, do they close upgrade tickets every time the students go home and as such the area goes around in circles.