3Com 10014299 manual Basic Configuration at, Enable L2TP, Enable/Disable L2TP, L2tp enable

606CHAPTER 43: CONFIGURING L2TP

addresses (RFC1918). The addresses allocated to remote users are private addresses belonging to an enterprise, thus the addresses can be easily managed and the security can also be improved.

■Flexible network charging

Charging can be fulfilled at both LAC and LNS sides at the same time, that is, at ISP (to generate bills) and Intranet gateway (to pay for charge and audit). L2TP can provide such charging data as transmitted packet number, byte number, start time and end time of the connection. And it can easily perform network charging according to these data.

■Reliability

L2TP supports the backup of LNS. When an active LNS is inaccessible, LAC can reconnect the backup LNS, which improves the reliability and error tolerance of VPN services.

Basic Configuration at

LAC

Enable L2TP

Basic configuration at LAC side includes:

■Enable L2TP

■Create a L2TP group

■Originate L2TP connection request and configure LNS address

Configure AAA and local users

The L2TP on a router can work normally only after it is enabled. If it is disabled, the router will not provide the related function even if the L2TP parameters are configured.

Perform the following tasks in the system view.

Table 665	Enable/Disable L2TP
Operation		Command
Enable L2TP		l2tp enable
Disable L2TP		undo l2tp enable

By default, L2TP is disabled.

Create a L2TP Group To configure related parameters of L2TP, an L2TP group should be added. The L2TP group is used to configure the L2TP functions on the router and facilitate the networking applications of one-to-one, one-to-multiple, multiple-to-one and multiple-to-multiple connections between the LAC and LNS. L2TP group is numbered separately on the LAC and the LNS. Hence, it is only necessary to keep the corresponding relations between the related configurations of L2TP group at LAC and LNS side (e.g., the peer end name of the tunnel originating L2TP connection request and the LNS address).

After a L2TP group is created, other configurations related to this L2TP group, such as local name, originating L2TP connection request and LNS address, can be performed in L2TP group view. L2TP group1 works as the default L2TP group.

Perform the following tasks in the system view.