adobe flash uses port 8890?

I am using Firefox 3.6.13 and I am getting firewall alerts that plugin-container.exe is using port 8890 when I play Mafia Wars or some other flash based games on facebook. Does anyone know why flash would use that port? The packets are TCP from my computer to 50.16.234.167, 50.16.235.182, 50.16.235.172, etc. It seems like those IPs are for Amazon in the APNIC database. Maybe these are for some sort of ads?

Plugin-container.exe is just the way Firefox works.

I’d create a zone [plugin.container - amazonaws.com] and put all the IP’s as they’re encountered into that zone Create a rule for plugin-container.exe that allows TCP out to [plugin.container - amazonaws.com] dest port 8890. Different sites will probably connect to different zones and different dest ports for associated flash content though. Set up new zones as you encounter 'em. Make additional rules to those zones w/associated dest ports as necessary.

As long as that’s happening at known & trusted sites and repeated to the same ports the traffic can be assumed to be benign. Eventually when the zone has enough IP addresses in it and plugin-container.exe has enough zones associated with it, you won’t get any more alerts. Don’t waste any time doing that if its a site you’ll probably never return to though.