<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Not quite sure of your point Geoff.<div><br></div><div>SIP has IP address details in the SDP - so if you have an ATA behind a NAT gateway then either the NAT gateway needs to understand how to do fixups or you have a Session Border Controller that does it (or both if you have a broken attempt at NAT fixup in your CPE).</div><div><br></div><div>ATAs behind NAT gateways is a VERY common deployment mechanism for consumer VOIP. Engin, for example, pretty much has it as a business model.</div><div><br></div><div>MMC<br><div><br><div><div>On 01/08/2008, at 2:46 PM, Geoff Huston wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Matthew Moyle-Croft wrote:<br><blockquote type="cite">On 01/08/2008, at 1:47 PM, Geoff Huston wrote:<br></blockquote><blockquote type="cite"><blockquote type="cite">After a decade of progressive NAT deployment, about the only applications<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">still doing the address in the payload thing are the brain dead dinosaurs. I suspect that the list beings and ends with ftp these days, because if<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">you do it today your novel application is just going to be fatally broken and<br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite">will never manage to achieve any form of critical mass in broad use.<br></blockquote></blockquote><blockquote type="cite">SIP does it,<br></blockquote><br>with gateways Matthew.<br><br><br></div></blockquote></div><br><div apple-content-edited="true"> <span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>-- <br>Matthew Moyle-Croft Internode/Agile Peering and Core Networks<br>Level 4, 150 Grenfell Street, Adelaide, SA 5000 Australia<br>Email: <a href="mailto:mmc@internode.com.au">mmc@internode.com.au</a> Web: <a href="http://www.on.net/">http://www.on.net</a><br>Direct: +61-8-8228-2909<span class="Apple-tab-span" style="white-space: pre; "> </span><span class="Apple-tab-span" style="white-space: pre; "> </span> Mobile: +61-419-900-366<br>Reception: +61-8-8228-2999 Fax: +61-8-8235-6909<br></div></div></span> </div><br></div></div></body></html>