Re: [Ekiga-list] no video: is video transferred on separate connection?

[Chris Vine <chris cvine freeserve co uk>]

On Mon, 28 Jun 2010 10:58:21 +0300
Jānis Rukšāns <thedogfarted gmail com> wrote:
[snip]
> Unfortunately most consumer grade routers and wireless access points
> are symmetric NAT. At least here (Eastern Europe) I have yet to see an
> off-the-shelf "wifi router" that wasn't symmetric NAT. And one tend to
> have very restrictive firewall policies at work too. Just like SIP,
> H.323 uses RTP for audio and video (it was originally designed for LAN
> use only) and the same NAT issues apply to H.323 as well.

A useful summary, but out of a sample of 5 consumer grade wireless
routers that I have used over the course of a few years, all have
implemented port restricted NAT (according to NatTester, which is
pretty reliable).

That is not to say that ekiga does not experience trouble with
NAT-traversal with some of them - it does.  Not all endpoint
independent port restricted NATing routers appear to be equal.  This is
when communicating with outside public SIP servers where media
hairpinning shouldn't be relevant (some of the routers have supported
hairpinning, some haven't), but there may be some correlation with that.

Chris