User manual

L2TP Overview
303532-A Rev 00
1-11
Bay Networks L2TP Implementation
In an L2TP network, the Bay Networks router is the LNS. LNS software operates
on the BLN
®
, BCN
®
, and ASN
™
platforms.
The Bay Networks LNS has the following characteristics:
• Each slot can act as an LNS, which means that one router can have many LNS
interfaces, each with its own address. You can have as many LNS interfaces as
there are available slots on the router.
• The LNS performs user authentication with a RADIUS server to prevent
unauthorized users from accessing the network.
• The LNS accepts only incoming calls; it does not place calls to the LAC.
• The Bay Networks L2TP implementation supports only IP traffic through the
L2TP tunnel. The LNS supports only numbered IP addresses.
• The router interface between the ISP and the corporate network (see
Figure 1-1
on page 1-7) is a leased line operating with frame relay, PPP
(including PPP multilink), or ATM. Bay Networks recommends that you use a
high-speed link, such as T1, for the leased connection.
• The LNS terminates PPP multilink and PPP encapsulated data within an
L2TP packet.
• The LNS operates with the LAC implementation configured on the Bay
Networks Model 5399 Remote Access Concentrator.
• The host (PC or router) dialing into the ISP network can be on the same
subnet as the IP interface on the LNS.
• The LNS supports RIP. RIP is particularly useful when the remote host is a
router, because it enables the LNS to learn routing information from the
remote router.
For instructions on how to configure a Bay Networks router as an LNS, see
Chapter 2
, “Starting L2TP.”