I'm running a sendmail 8.11.6 mail server behind a firewall.  I allow
internal users get mail from the server with POP3 and send messages out
with SMTP thru the server.  I did this by allowing the local network to
relay off the server

What I would like to do is allow users from the outside of my firewall
to be able to get their messages with POP and be able to send messages
thru my sendmail SMTP server.  I want to be able to have my remote users
to be able to setup POP and SMTP server information in their e-mail
client like they would for an ISP.  The remote users will have different
IP addresses

My question, how do I setup my sendmail server to only allow
authenticated users to be able to send mail thru my server, and not make
the server an open relay. (Like an ISP)

I've searched Yahoo and a sendmail book, but I haven't really found what
I'm looking for.  (I don't know if I've been using the correct
terminology, so far i've been looking for things like - client smtp
authentication relay ...) Does anyone know how to do what I'm to do, or
can point me in the right direction.

Thanks for any help
Jim Streit