restricting access to a server

We want to secure access to a server by restricting the number of users who can login to it. Our users are NIS users. Only few of them can telnet/ssh this server.

Do you have any idea on how to implement that?

thanks.

There's a few ways, tcp wrappers or netgroups spring to mind.

A 2 second google would have answered this :rolleyes:

-c