thx , david55
i use peer but same problem.
=================== Notebook ========================
================extension.conf========================
[phones]
include => internal
include => remote
[internal]
exten => 24501,1,Dial(SIP/24501)
[remote]
exten => 24500,1,Dial(SIP/serverPC/24500)
exten => 24500,2,Hangup()
[serverPC_incoming]
include => internal
=====================sip.conf==============================
register => serverNB:pass_serverNB@172.30.232.106/serverPC
[serverPC]
type=friend
secret=pass_serverPC
context=serverPC_incoming
host=dynamic
disallow=all
allow=ulaw
[24501]
username=24501
secret=24501
host=dynamic
type=friend
context=phones
======================== PC ===========================
================extension.conf==========================
[internal]
exten => 24500,1,Dial(SIP/24500)
[phones]
include =>internal
include =>remote
[remote]
exten => 24501,1,Dial(SIP/serverNB/24501)
exten => 24501,2,Hangup()
[serverNB_incoming]
include => internal
===============sip.conf===========================
register => serverPC:pass_serverPC@172.30.232.230/serverNB
[serverNB]
type=friend
secret=pass_serverNB
context=serverNB_incoming
host=dynamic
disallow=all
allow=ulaw
[24500]
username=24500
secret=24500
host=dynamic
type=friend
context=phones