Sip.conf

[200]
disallow=all
secret=mysecret
allow=alaw
type=friend
host=dynamic
context=extensions
reinvite=no
canreinvite=no
qualify=yes
callerid="200" <200>
nat=yes
outgoinglimit=2
incominglimit=2
dtmfmode=rfc2833



[201]
disallow=all
secret=mysecret
allow=alaw
type=friend
host=dynamic
context=extensions
reinvite=no
canreinvite=no
qualify=yes
callerid="201" <200>
nat=yes
outgoinglimit=2
incominglimit=2
dtmfmode=rfc2833


[123456]

disallow=all
secret=mysecret
allow=alaw
type=friend
host=dynamic
context=pstn
reinvite=no
canreinvite=no
qualify=yes
at=yes
outgoinglimit=2
incominglimit=2
dtmfmode=rfc2833


Extension.conf

[extensions]

; define what to do when my extension is called
exten => 200,1,Dial(SIP/200,60)
exten => 200,2,Congestion
exten => 200,102,Busy

;here is another sip extension
exten => 201,1,Dial(SIP/201,60)
exten => 201,2,Congestion
exten => 201,102,Busy



; Test number
exten=> 199,1,Answer
exten=> 199,n,Ringing
exten=> 199,n,Wait(2)
exten=> 199,n,saydigits(${CALLERID(num)})
exten=> 199,n,Wait(2)
exten=> 199,n,hangup 


[pstn]
; here is where we put the stuff to handle incoming calls

exten => 123456,1,Dial(SIP/200&SIP/201,60)
exten => 123456,2,Congestion
exten => 123456,102,Busy