[asterisk-users] Choose IAX or SIP trunking?

[Kirill 'Big K' Katsnelson]

Steve Edwards wrote:
> Some say the audio quality is better with SIP. My experience has been with 
> "low volume" (xx) calls across the internet and "high volume" (xxx) within 
> the same cabinet.

My understanding was that IAX encapsulates the same RTP traffic, or, and 
the very least, same stream of data encoded by a codec. Is that not true 
in case of IAX? How can a transport protocol affect volume--or quality 
(lest it is dropping packets)?

  -kkm, now puzzled.