Is there a limit to the number of XBox 360's you can connect using system link?

I'm inviting some people round for a Halo night and I'm going to ask them to bring their own TVs/XBox 360s is there a limit to the number of XBox 360s you can connect using system link? I have a switch and I'll be connecting them all up to a hub which should assign them IP addressed using DHCP.

Last time I did this we had 4 x boxes connected ups with 12 players (One screen was too small to play with 4 players on it) I know that Halo only lets you play with 16 players locally, I was wondering if that was due to a 4 XBox Limitation.

The system limit is apparently 16.

From their support site:

System link play is a form of multiplayer gaming that allows you to connect 2 Xbox 360 consoles with a cable or up to 16 consoles over a network. With linked consoles, multiple players can play the same game. This type of multiplayer gaming is different from split-screen multiplayer gaming, in which all the players are connected to the same console.