...
Lets look closely on how clients sessions gets authenticated and established over the LAC.
View file
- Client initiates PPPoE call
- LAC and Client begins LCP negotiation
- after CHAP has been negotiated, LAC sends CHAP challenge
- Client sends CHAP response
- LAC checks whether client session should be forwarded to the LNS based on received domain name. Check can be done locally or using RADIUS server. Client also can be authenticated here before forwarding session.
- LAC brings up an L2TP tunnel
- LNS checks if the LAC is allowed to open a tunnel and run the authentication process. The Tunnel is up and ready to forward VPDN sessions.
- LAC forwards negotiated with the client LCP options, username and password to the LNS
- LNS authenticates the client locally or using RADIUS and sends CHAP response
- IP Control Protocol (IPCP) phase is performed, IP addresses and routes are installed. At this point sessions is considered established.
...