Jitter
 

I noticed on the R36 firmware beta thread that there appears to have been a reduction in jitter with the new firmware.

I have the 50 Mb/s VM Business cable service. While this uses the same Superhub, the firmware is different. I am running V5.5.2R04T15-BU This was an update to fix L2TP tunnel drops, which affected customers with fixed IP addresses. However that release did not change jitter, which for me was around 14-20 ms previously.

However I am now noticing a significant drop to 2-4ms of jitter with a much improved thinkbroadband graph (see below).

Given that firmware hasn't chaged here, something else has changed to cause this improved performance.

I am fed from the New Malden CMTSs which are due for the full speed doubling programme from April-July, so I wonder if work has taken place for that that has improved things?

I still only have 4 downstreams and 1 upstream. That might not change for business users I guess since the speed doubling programme doesn't apply to business users only residential, so not sure if they will add more downstreams for business users.

http://www.thinkbroadband.com/ping/s...30-06-2012.png

It looks like something changed on Thursday:-

http://www.thinkbroadband.com/ping/s...28-06-2012.png

Re: Jitter
 

I wonder if it's a change in the peering to TBB. When I was on 50Mbps I usually struggled to see anything over 30mbps on TBB even though Speedtest.net testers always showed ~ 50Mbps. Now I'm on 60 I see 60 from TBB so something has changed. My own TBB monitor has been looking better over the last couple of weeks or so too.

Re: Jitter
 

Most peoples looks better across the country, there are so many threads about it already and i am still on R30 and the graph is awesome now.

Re: Jitter
 

No.

Re: Jitter
 

I don't think it's that as pingtest.net shows significantly improved results now too.

It looks like something has been done in the Virginmedia network that has had a positive effect, which is good!

Re: Jitter
 

i have post and to post your monitor results
It seems (of course i am not sure) is from virgin media because before at my UBR was getting this info
cpc3-camd...something
Now cpc5-camd...something
So to me it seems they have done something to UBR, maybe a change in card slot

Re: Jitter
 

Or just a change in ip.

Re: Jitter
 

Odd, I have not noticed a change at all to my tbb graph and still get terrible speeds from their speed tests although most graphs do seem to have improved.

Re: Jitter
 

hmmmmm....change ip or routing ... mentioned this, it may be possible because when the latency lowered it did not get disconnection....then something it tells me with the 8000 pilots will test first i bet is the ones that the latency has lowered (i am not in the beta test)

But then can how explain some one the change in the UBR from cpc 3 to 5?

Re: Jitter
 

So what's your guess?

Re: Jitter
 

There has been a similar big improvement here in Bromley too :), but it looks like it happened on Monday 25th June at around 11:00am here.

http://www.thinkbroadband.com/ping/s...25-06-2012.png

Wonder what they did?

Re: Jitter
 

Because your IP will have changed.

Go from modem mode to router mode, you'll be on a different IP and a different CPC, due to a change in the block of IPs. Very rarely you get one on the same block as the last.

I used to do this all the time to improve my connection, trying to find the least congested. My various weeks of playing around cloning macs i had many different IPs.

---------- Post added at 14:15 ---------- Previous post was at 14:14 ----------

Maybe it's a network wide upgrade on their UBRs, specifically the ones that are showing increased jitter...

Re: Jitter
 

Local network improvements

Re: Jitter
 

Thank youuuuu :)

Re: Jitter
 

Admittedly they've either improved my local network or the neighbourhood torrent freak now has the entire output of 20C Fox et. al. on Bluray and has retired to watch them all but I used to see garbage results from TBB when my local connection was OK and now they are fine. It seemed more likely to me that the Linx loading had reduced somehow although whether that was down to increased capacity or re-routing something else I've no idea.

Re: Jitter
 

This is mine as of 30 seconds ago, I type very slowly

[img]Download Failed (1)[/img]

Re: Jitter
 

Can't have been LINX loading or rerouting because only end-user connections saw any change.

Core nodes, CMTS, and everything else saw no change. If it were core network or interchange improvements anything on VM's network would be responding faster and not just end users on cable modems.

Re: Jitter
 

Surely the ping packets traverse the entire VM network? What about my improved speedtests from TBB?

Re: Jitter
 

Also that not everyone is seeing improvements.

Whenever I did ping analysis of my VM connection the following pattern was consistent.

No or almost no jitter right up until my CMTS.
Occasionally the CTMS itself would have some jitter but usually the jitter started at my ip.

This is harder to diagnose on outbound trace's because then the jitter shows on every hop but easy on inbound. So whatever VM's peering issues are they werent the cause of VM's jitter.

Also there has been VM graphs that have been like the improved ones posted that have existed for many months, my neighbour is on a upstream channel that seems to be very lightly utilised or maybe that channel already had the new configuration which seems to have been rolled out now to some other users.

Re: Jitter
 

I'm in a poor position to judge.

When I first noticed problems with TBB I was on 50 and there was no noticeable local congestion. Then came the local problems which I put down to a single 100/10 sale as the onset was so fast plus you'd sometimes see a huge improvement for a short time then really quickly back to dross (for 50) so I downgraded to 10 which I pretty much always got.

I first noticed better TBB charts maybe a month or so back - somewhere around the time I ordered Infinity. Then Openreach naffed me around so I decided to give VM another chance and upgraded to 60/3. Over this period lots of people have been reporting improvements + R36 which I'm now on offers less jitter.

Given that lot I've really no idea why I now see headline rate speedtests from TBB despite it all still going through Linx as it always has.

Re: Jitter
 

as ive just posted in another thread discussing the same subject I think VM have made p2p throttling far more aggressive, these could be the improvements we are seeing