[Asterisk-Users] voice over atlantic

[David Hajek]

Hi-

I'm using IAX between two boxes, where one box is located in US and the
second in Europe. I'm trying to achieve the best voice quality and
mainly reliability between these boxes and looking for hints and
experience of others. 

Facts:
- Asterisk 1.0.7
- RTT varies from 130-170 ms, depends on time and actual Internet
throughput

Questions:
- What is the sugested codec for such setup? Now I'm using ULAW, but
realizing it may not be the best choice. Sometimes I can hear broken
audio. Maybe speex is better choice? 
- Jitter buffer, yes/no? What are the suggested values. Currently I'm
using these values:
jitterbuffer=yes
dropcount=10
maxjitterbuffer=500
maxexcessbuffer=300
minexcessbuffer=20
jittershrinkrate=2 
- Trunking? Is it reliable enough?

Thanks for any hints.

--
David