The OS/2 Warp Server TCP/IP V4.21 stack includes Virtual Private Network (VPN) capability.
The actual implementation is based on the IP Security Architecture (IPSec) framework,
which provides security at the network layer.
While most of the VPN functionality of IPSec is not of particular interest here,
its packet filtering capabilities are, as these allow it to be used as a firewall
on a multi-homed host.
IPSec consists of four device drivers (only two of which are essential here)
and a number of configuration utilities, which will be looked at in the next section.
Now go to Basic Configuration