Hi,

what user agent are you using? IMSDroid or similar?
Quick note: 3GPP SMS over IP (sent as SIP MESSAGE) is never direct, but always store & forward, so you need an SMSC...

Thanks,
Carsten

Am 21.11.2015 6:01 nachm. schrieb "Thierry Luo" <langsir@yeah.net>:
Hi All,

I installed kamailio on Ubuntu as IMS pCSCF/iCSCF/sCSCF. REGISTER is fine,
but when I tried to send a MESSAGE (SMS) from one user to another, it was
always not successful. I captured IP packets on the server, and it seemed
that the error was caused on pCSCF.

User1 and User2 are both behind their NAT network.  Suppose User1's private
IP is Private_IP1, and User1's public IP (on router) is Public_IP1, and
User2's private and public IPs are Private_IP2 and Public_IP2:

User1                                pCSCF
iCSCF                                     sCSCF
user2
               MESSAGE
            ---------------->
                                                                   MESSAGE

--------------------->

MESSAGE

------------------->

MESSAGE

<-----------------------------------------------------

MESSAGE

----------------------------------------------------------------------------
---->


Unfortunately, from the captured data on the server, in the last step, the
MESSAGE was sent to the Private_IP2 of User2. It should be sent to the
Public_IP2. Of course, the datagram with the destination of Private_IP2
cannot reach User2 successfully.

Please help analyze why the pCSCF sent the MESSAGE packet to User2's private
IP instead of public IP. The configuration file was attached for reference.


BR.
Thierry Luo

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