<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<HTML>
<HEAD>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii">
<META NAME="Generator" CONTENT="MS Exchange Server version 6.0.4417.0">
<TITLE>Multiple IPs and SIP</TITLE>
</HEAD>
<BODY>
<!-- Converted from text/plain format -->
<P><FONT SIZE=2>This topic has already been brought up lately, but I'd like to inquire if there are any news.</FONT>
</P>
<P><FONT SIZE=2>I have 2 IP addresses assigned to my ethernet card (eth0 and eth0:0) that are on 2 different subnets (one public, one private), because our PSTN gateway provider has established a private link with us using private addresses. Yes, that's not exactly "clean", 2 ethernet cards would be better, but it shouldn't make a difference for this issue.</FONT></P>
<P><FONT SIZE=2>Now the problem: I have asterisk bound to 0.0.0.0 in sip.conf, so it binds to every address I have. The routes in my system are configured correctly. But as soon as asterisk tries to send a SIP packet to a private address, using eth0:0, the following happens:</FONT></P>
<P><FONT SIZE=2>- the packet actually arrives at my PSTN provider's border gateway</FONT>
<BR><FONT SIZE=2>- the sender IP address in the UDP packet is correct, it's my private address, so linux did its routing job correctly</FONT>
<BR><FONT SIZE=2>- the SIP packet contains my public (!) address in the "From" and "Contact" fields, which is wrong, and confuses our PSTN provider's gateway, which in turn tries to send the reply to our public address, which it will never find, because their server is on a private network only</FONT></P>
<P><FONT SIZE=2>This has to do with the fact that SIP wants to encode ethernet packet information in a higher layer, which is somewhat stupid IMHO, but I think we have to live with this :)</FONT></P>
<P><FONT SIZE=2>We're using CVS-HEAD-08/24/04 (yes, I have to upgrade sometimes...). Has this issue been addressed lately, or is it somehow unsolvable?</FONT></P>
<P><FONT SIZE=2>Thank you everyone</FONT>
<BR><FONT SIZE=2>-Manuel</FONT>
</P>
</BODY>
</HTML>