limit to number of consoles?

I'm sure there must be a limit somewhere.
If nothing else there are only about 64K tcp ports,
but I'm wondering of there is some much lower limit
that I will run into first?  Right now we are at
667 consoles and growing.  Is this something I need
to worry about soon or do I have plenty of "headroom"?


Thanks,
John
PS, our devices are mostly connected through cyclades
    terminal servers in raw mode, but we do have some
    using LAT terminal servers and a few connected via
    a USB-serial adapter.  We are trying to phase out
    the LAT TSs owing to their age and scarcity (perhaps
    we are the worlds largest repository of DECserver 90s
    at this point :)