[asterisk-users] Best Practices: Empirical measure of call latency

[asterisk-users at kfife.mailworks.org]

I would like to hear your favored method to obtain an empirical measure
of latency in the media path.  
I'm doing several things that bring the media path through asterisk, and
this would allow me to make informed decisions about

(a)PSTN termination providers
(b)DIDs in local and remote locations (and variance between ITSP's)
(c)time to/from various cellular networks  (and variance between ITSP's)

Thanks!  Your opinion would be greatly appreciated
-Karl Fife

p.s.
Speaking of latency, I've noticed that some sip endpoints (i.e. Aastra
57i Wireless) add significant latency.  It would be interesting to do an
apples-to-apples comparison between with various fxo/dect, sip/dect,
wi/sip, fxo/Spread-spectrum digital , and fxo/analog 47/900/2400mhz.