The internal interface is used as the endpoint for a remote connection.
When a remote client connects, the server acquires an IP address from the
address pool to be the server end of the point to point connection. When a
remote client connects, the internal interface becomes active and is the
"virtual" interface for the remote connection.
Traffic between this interface and the LAN interface is controlled by
the server. If the remote client and the LAN machines are in different IP
subnets, traffic is routed between them by the RRAS server. If they are in
the same IP subnet, the server acts as a proxy for the remote machine and
relays traffic onto the LAN. It receives LAN replies addressed to the client
(using proxy ARP) and relays them over the point-to point link.
Note that this is purely an IP connection. It does not carry LAN
broadcasts. Name resolution will only work if you have a name server running
on the LAN (DNS or WINS). Otherwise you will need HOSTS or LMHOSTS files on
the client with entries for any LAN machines you want to access by name.
"The Ricster" <(E-Mail Removed)> wrote in message
news:04d401c3bb91$95bbc9f0$(E-Mail Removed)...
> My VPN server has only one nic card installed. Why are the
> Loopback and Internal interfaces listed in RRAS, and how
> are they used. Should not my active interface be the nic,
> although when installing, I got the message that the
> interface should be only used for ras? (which would mean
> that I could not see the rest of my lan).
>
> Please help (since I cant seem to get any replies to my
> other more important posts! 
>