User's Manual

34
Network Planning
3
Virtual Private Network
The Gateway supports three of the most commonly used VPN protocols – PPTP,
L2TP and IPSec. These protocols allow remote users to establish a secure
connection to their corporate network. If your service provider supports VPNs, then
any of these protocols can be used to create an authenticated and encrypted tunnel
for passing secure data over the Internet (i.e., a traditionally shared data network).
The VPN protocols supported by the Gateway are briefly described below.
Point-to-Point Tunneling Protocol – Provides a secure tunnel for remote client
access to a PPTP security gateway. PPTP includes provisions for call origination
and flow control required by ISPs.
Layer Two Tunneling Protocol – L2TP includes most of the features provided by
PPTP, but has less overhead and is more suited for managed networks.
IP Security – Provides IP network-layer encryption. IPSec can support large
encryption networks (such as the Internet) by using digital certificates for device
authentication.