sip.conf

root@sip:~ # service pf restart
Disabling pf.
Enabling pf.
root@sip:~ # cat /usr/local/etc/asterisk/sip.conf
[general]
transport=udp
; tcpenable=yes
; qualify=yes
port=5060
bindaddr=192.168.0.2
; disallow=all
allow=ulaw
allow=alaw
allow=gsm
nat=yes
; public_ip=82.177.238.240
externip=82.177.238.240
localnet=192.168.0.0/255.255.255.0

[friends_internal](!)
type=friend
host=dynamic
context=from-internal
; disallow=all
allow=ulaw
allow=ulaw
allow=alaw
allow=gsm

[demo-alice](friends_internal)
secret=password

[demo-bob](friends_internal)
secret=password