Ethernet Card Limitations to Number of Connections?

[Michael K. Smith - Adhost]

Hello All:

Are there any physical limitations to the number of connections
(TCP/UDP) that are determined by the physical interface itself?  We have
a PF load-balancing solution in place in front of a large number of mail
servers and we're considering using the same boxes to front our Name
Server/Name Resolvers.  I'm concerned that the single uplink port on the
PF box will be overloaded with the number of connections.

Any insights would be greatly appreciated.

Regards,

Mike