3Com WL-603 manual Operation, Connection between two devices, make sure that they support

VPN 117

VPN	The Router has a Virtual Private Network (VPN) feature that provides a
	secure link between remote users and the corporate network by
	establishing an authenticated and encrypted tunnel for passing secure
	data over the Internet. The Router supports three modes of VPN
	operation:
	■ IPSec (IP Security) — provides IP network-layer encryption. IPSec can
	support large encryption networks (such as the Internet) by using
	digital certificates for device authentication. When setting up an IPSec
	connection between two devices, make sure that they support the
	same encryption method.

Note: Enabling IPSec VPN disables pass-through to IPSec and L2TP over IPSec Virtual Servers on the LAN. Pass-through outbound from clients on the LAN to servers on the Internet is unaffected.

■PPTP (Point-to-Point Tunneling Protocol) — provides a secure tunnel for remote client access to a PPTP security gateway. It is not as secure as IPSec but is easy to administer. PPTP does not support gateway to gateway connections and is only suitable for connecting remote users. Check that your ISP’s routers support this protocol before you use it.

Note: Enabling the PPTP Server disables PPTP pass-through to a Virtual Server on the LAN. Pass-through outbound from clients on the LAN to servers on the Internet is unaffected.

■L2TP over IPSec — this is a combination of two protocols. L2TP is used to authenticate a user, and IPSec is used to encrypt data. L2TP over IPSec does not support gateway to gateway connections and is only suitable for connecting remote users. Check that your ISP’s routers support this protocol before you use it.

Note: Enabling L2TP over IPSec disables pass-through to IPSec and L2TP over IPSec Virtual Servers on the LAN. Pass-through outbound from clients on the LAN to servers on the Internet is unaffected.

Using the VPN Tunnel Configuration screen, you can add new IPSec, L2TP over IPSec and PPTP connections, and to edit existing connections. When adding or editing values on this screen remember that both ends of the connection must contain the same information.