How does IAX2 work?

I am using asterisk 1.4.25 with freepbx 2.5.5 compiled on ubuntu server 8.04

I am confused about a bunch of specific details about how the IAX2 protocol works.

I want to use IAX2 trunks to route calls between multiple of site systems.

is there any documentation about how the procols works between two systems

and what the major differences are between them

allow=ulaw <-- codex right?
type=friend <-- what is the difference between friend user and peer ?
context=from-pstn < – haven’t quite figure this one out?
nat=no <-- does this do anything?
insecure=very <-- this means no auth right ?
host=x.x.x.x <-- who I want to talk to right?
dtmfmode=rfc2833 <–key tone right ?

in context= what are my options and what does it do.

a lot of this might because I am an freepbx user and not a hard core asterisk config file person.

any help for a blind man in a desert would be great

thank you.

Hi

Sorry to say but you are very confused here as the options you posted are for SIP and not IAX2

For details on the settings check the sample config file as this will list all the avalible options

Ian