Neil Turner's Blog

Blogging about technology and randomness since 2002

I Chat Through Walls

One of my friends picked himself a MacBook a few weeks ago and now that I have mine we’ve been comparing notes about how utterly awesome they are. But one thing neither of us have tried was using iChat AV, with full voice and video, so of course this was what we did this evening.
However, it took quite a bit of trial and error to get working, especially as the troubleshooting guide in iChat Help doesn’t get much above the ‘make sure you have a broadband internet connection’ level. Here are the two things that helped us get going:

  • In iChat, open up Preferences, and choose Video. Then, under Bandwidth Limit, set it to something like 500KB/s, rather than the default.
  • If you’re behind a NAT firewall, like me, you need to allow UDP connections on port 5060 and on ports 16384 to 16403 and have them forward to your machine.

With that done, we were able to have a two-way video conversation with no problems. Though iChat will open the ports on your Mac firewall, if you have another firewall downstream of your computer then you will need to open ports on that manually – Mac OS X doesn’t natively support UPnP or similar technologies that do this for you, which is a shame.


  1. I have so much trouble with all IM’s and firewalls/routers. They’re the bane of my existence. And the two most persistently annoying out of all of them are, getting fast (direct) file transfers with an msn buddy and getting video chat to work in iChat.
    Turned out that not only did I have to set up the port forwarding rules but that iChat also has a problem with some routers if uPnP is enabled (even though it doesn’t use it… go figure). So everytime I want to video chat with someone I have to visit and turn off uPnP, so annoying.

  2. Since when did WLM video call not suffice?

  3. Since I got a MacBook which didn’t have Windows on it 🙂 . Microsoft Messenger, the MSN program for the Mac, doesn’t support video messaging, but we both had iChat, which does, and AIM accounts.

  4. My iChat won’t let me audio or video with other users – why is this – text is fine but can’t do anything else?