Accessing network outside of office.

We have exchange server running on our NT server but use Novell 4.11 as our primary network. We use RAS to access our interoffice email from the exchange server when we are not in the office and use the proxy to serf the internet. My question is with what I described to you above is it possible for us to access our server when we are outside of the office with what I mention above through RAS and if yes please explain. Also if what we have above is not enough please explain throughly what wecan do to make this possible. We urgently need a response to this question as we try to expand our offices.