In reply to a post by tommy45:

it's the underlying cause if such exists that could be key to why this is happening, and should this be coupled with a lower level of throughput ,it would reinforce the theory of some links reaching full or near to full utilisation (congestion) or something else that isnt able to cope with the peak time traffic flow properly

It's probably a side-effect of their traffic management/queuing systems, but 40ms of jitter at peak times isn't a bad enough issue (to them) to warrant a full-scale overhaul of their network. Maybe if the customer base grew and regular peak jitter rose to 80ms or 100ms action would be taken. We do have to consider that Plusnet are a budget ISP, whereas this would be considered a fault in need of a fix at BE (of old?).

Interesting that ICMP is in the titanium queue and still suffers the lag.

In reply to a post by Oliver341:

It's probably a side-effect of their traffic management/queuing systems, but 40ms of jitter at peak times isn't a bad enough issue (to them) to warrant a full-scale overhaul of their network. Maybe if the customer base grew and regular peak jitter rose to 80ms or 100ms action would be taken.

But reading through the Plusnet forums there are complaints about lower than normal throughput during peak times, if the two are linked then i would be suprised if it was soley down to there traffic management,

In reply to a post by tommy45:

But reading through the Plusnet forums there are complaints about lower than normal throughput during peak times, if the two are linked then i would be suprised if it was soley down to there traffic management,

I would expect throughput-affecting latency to result in an elevated green line (e.g. congestion), but this latency issue seems not to do that.

40ms is a lot of jitter.

however plusnet staff seem to be stating it isnt affecting tcp and actual gaming packets so as such isnt a major problem.

be aware if average rises to 40ms that isnt 40ms jitter. Whilst the plusnet graphs look dodgy I suspect the jitter isnt as high as 40ms on them.

what does pingtest.net report at peak?

There were complaints in Feb. That was a config issue which was resolved and unconnected to the TM platform.

If we started seeing performance issues due to kit/config, we'd be all over it to make sure we knew what was going on and trying to fix. Our reporting suites aren't highlighting anything to be concerned about at the minute.

This is why online communities are great. They help us spots issues fast.

In reply to a post by Chrysalis:

be aware if average rises to 40ms that isnt 40ms jitter. Whilst the plusnet graphs look dodgy I suspect the jitter isnt as high as 40ms on them.

As I understand it, jitter is the difference between minimum ping and maximum ping. Typically, the Plusnet graphs show a minimum ping of 20ms with maximum ping reaching 60ms ping at peak. 60ms - 20ms = 40ms jitter.

Wikipedia defines it

In the context of computer networks, the term jitter is often used as a measure of the variability over time of the packet latency across a network. A network with constant latency has no variation (or jitter).[3] Packet jitter is expressed as an average of the deviation from the network mean latency. However, for this use, the term is imprecise. The standards-based term is packet delay variation (PDV).

That implies "jitter" is the average, not the maximum.

In an example of a base latency of 10ms, with 1 packet getting a 40ms delay followed by 99 packets with zero delay: The mean latency is 10.4ms, and the total deviation is 79.2ms - so the jitter is 0.8ms

It also says that the term is imprecise, but I think they mean that people use different definitions.

I wonder how pingtest.net calculate it. They say:

"Once you understand ping, jitter should also make sense. Jitter is merely the variance in measuring successive ping tests. Zero jitter means the results were exactly the same every time, and anything above zero is the amount by which they varied. Like the other quality measurements, a lower jitter value is better. And while some jitter should be expected over the Internet, having it be a small fraction of the ping result is ideal."

I suppose that doesn't really explain their method of calculation though.

no it isnt.

eg.

10
10
10
80
10
10
10
10
10

is not 70ms jitter.

In reply to a post by Chrysalis:

no it isnt.

eg.

10
10
10
80
10
10
10
10
10

is not 70ms jitter.

Ok. What would be the jitter in your example?