SIP VIA Header has wrong IP - internal NAT IP

[padge]

Hi, Hope someone can help.

I am evaluating 3cx phone manager in a test environment.

I have got 3cx phone manager (latest version) installed on an XP machine behine a NAT firewall.

Firewall test goes ok from 3cx admin pages. VOIP line registers ok with my SIP provider (node4 in UK), and is shown as active in line status page.

I am using 3cx voip client, which registers ok, and can make voip calls to another 3cx voip client on the internal network.

Problem is that I can't make external calls through the SIP provider. My provider has said it is because the SIP VIA header contains the internal IP address of the 3cx server and it needs to have the public IP address of the router. How can I set phone manager up to send this IP in the via header?

Thanks in advance for any help or advice.

I'm using wireshark to see SIP traffic, so I can confirm that the VIA header has the wrong IP

 

[nitup]

I can confirm that the VIA header has the wrong IP

Can you refer to some RFCs that proves your words and specify that exactly external IP MUST be passed in Via header?

 

[zoomzoomvince]

I'm also trying to use Node4 and they have also given me the same response.

"According to the RFC 3261 via header should be included the client's host name or network address as in the example below ;

Via: SIP/2.0/UDP 192.0.2.1:5060;branch=z9hG4bK87asdks7
20.42 Via
A Via header field value contains the transport protocol used to send the message, the client's host name or network address, and possibly the port number at which it wishes to receive responses."

Has anybody got outside calls working with Node4 ???

 

[zoomzoomvince]

This is what Node4 are saying. It looks like the Via header doesn't contain our IP address/port.

A Via header field value contains the transport protocol used to send the message, the client's host name or network address, and possibly the port number at which it wishes to receive responses.

However we've observed that this information is missing in the Via line.

INVITE sip:[email protected]:5060 SIP/2.0
Via: SIP/2.0/UDP ;branch=z9hG4bK-d8754z-d00ec81064266e2f-1---d8754z-;rport
From: "1454" <sip:[email protected]:5060>;tag=f440d027
To: <sip:[email protected]:5060>
Call-ID: N2I0YzI4M2I2YzE2ZjZiMjg2Y2RjYmM0NGQxNjg1NDk.
CSeq: 1 INVITE
Contact: <sip:[email protected]:5060>
max-forwards: 70
user-agent: 3CXPhoneSystem 6.0.805.0
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REGISTER, SUBSCRIBE, NOTIFY, REFER, INFO
Content-Type: application/sdp
Content-Length: 282

 

[zoomzoomvince]

Well after several hours speaking to Node4 tech support I have given up on them as they just don't seem interested in getting it to work and I am moving to VOIP Unlimited instead.