AIS Router AI2524 - Manual (Page 253)

Chapter 11: AI2524 Sync PPP Configuration Steps
August 1997 Page 11-27
2524UM
Note: The MMP feature uses VPDN to connect multiple PPP
sessions for which individual dial-in calls have arrived on
different stack group members. VPDN provides speed and
reliability for the setup and shutdown of Multilink PPP.
Complete these steps to create a a VPDN connection between a remote
user and the home LAN:
1. The remote user initiates a PPP connection to the ISP using the an-
alog telephone system or ISDN.
2. The ISP network access server accepts the connection.
3. The ISP network access server authenticates the end user with
CHAP or PAP. The username is used to determine whether the
user is a VPDN client. If the user is not a VPDN client, the client
accesses the Internet or other contacted service.
4. The tunnel endpoints—the network access server and the home
gateway—authenticate each other before any sessions are at
tempted within a tunnel.
5. If no L2F tunnel exists between the network access server and the
remote user’s home gateway, a tunnel is created. Once the tunnel
exists, an unused slot within the tunnel is allocated.
6. The home gateway accepts or rejects the connection. Initial setup
can include authentication information required to allow the home
gateway to authenticate the user.
7. The home gateway sets up a virtual interface. Link-level frames
can now pass through this virtual interface through the L2F tunnel.
Figure 11-2 illustrates a VPDN connection from a remote user, who
makes a local call, to the corporate network, through an end-to-end
L2F tunnel (shown by the dotted line).