Nortel Networks manual Components of an L2TP Network, Remote Host

Configuring L2TP Services

Components of an L2TP Network

The following sections describe the components of an L2TP network. For illustrations of L2TP networks, see Figures 1-1 and 1-2 on page 1-7.

Remote Host

At the remote site is the user who wants to dial in to the corporate network. The remote user can be located anywhere, provided that the user can dial into an ISP network using a PC or a router. The ISP provides the connection to the Internet.

The host at the remote site can be a PC or router that uses PPP for dial-up connections.

•If the PC or router does not have built-in L2TP software capabilities, it dials into a LAC, which provides a tunnel across the Internet to the corporate LNS.

•If the PC or router is an L2TP client, that is, it has built-in L2TP functionality, the L2TP client software provides a tunnel through a RAS across the Internet to the corporate LNS. A LAC is unnecessary with an L2TP client.

The main difference between connecting an L2TP client and a nonclient is the starting point of the tunnel. For an L2TP client, the tunnel begins at the PC or router; for a non-L2TP client, the tunnel begins at the LAC. All tunnels end at the LNS.

Note: This guide’s primary focus is on an L2TP network between a remote host that does not have built-in L2TP capabilities and uses a LAC, rather than a RAS.

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