Virtual Private Networking
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L2TP
The
Layer Two Tunneling Protocol
was developed by Microsoft and Cisco as a multi-
purpose network transport protocol.
Many DSL ISPs use L2TP over ATM to create tunnels across the Internet backbone.
The SnapGear L2TP implementation can only run L2TP over Ethernet since it doesn't
have an ATM adapter. L2TP packets are encapsulated in UDP packets on port 1701 and
sent over Ethernet to the L2TP server.
L2TP VPN client
The SnapGear L2TP VPN client is configured and operates in a similar way to the PPTP
VPN Client.
Figure 9-30