Re: [Bloat] DSLReports Speed Test has latency measurement built-in

[Mikael Abrahamsson <swmike@swm.pp.se>]

On Thu, 7 May 2015, Jim Gettys wrote:

> Ideally, we need to get someone involved in WebRTC to help with this, to 
> present statistics that may be useful to end users to predict the 
> behavior of their service.

If nothing else, I would really like to be able to expose the realtime 
application and its network experience, to the user.

For the kind of classic PSTNoverIP system I mentioned before, it was 
usually possible to collect statistics such as:

Packet loss (packet was lost completely)
Packet re-ordering (packets arrived out of order)
Packet PDV buffer miss (packet arrived too late to be played on time)
I guess it's possible to get PDV buffer underrun or overrun (depending on 
how one sees it), if I get a bunch of PDV buffer misses and then I halt 
play-out to wait for the PDV buffer to fill up, and then I get 200ms worth 
of packets at once and I don't have 200ms worth of buffer, then I throw 
away sound due to that...

So it's all depending on the whole machinery and how it acts, you need 
different statistics. How to present this in a useful manner to the user 
is a very interesting problem, but it would be nice if most VoIP 
applications at least had a "status window" where these values could be 
seen in a graph or something similar to "task manager" in windows.

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se