HP FlexNetwork MSR2003 Configuration Manual page 349

5. The server and the client exchange negotiation acknowledgment packets protected by using
the keys.
6. The server and the client use the keys to protect subsequent packets if they can restore the
protected negotiation acknowledgment packets.
If they cannot restore the packets, the negotiation fails.
Figure 143 Connection initialization process
Registration
Figure 144 shows the following registration process:
1. The client sends the server a registration request that includes its public address, private
address, and the connected private network.
2. The server sends the client an identity authentication request that specifies the authentication
algorithm.
If authentication is not required, the server directly registers the client and sends the client a
registration acknowledgement. VAM supports both PAP and CHAP authentication.
3. The client submits its identity information to the server.
4. The server performs authentication and accounting for the client through the AAA server.
5. The server sends the client a registration acknowledgement that includes hub information.
Figure 144 Registration process
Client
1) Registration request
2) Identity authentication request
3) Identity information
4) Registration acknowledgement
Tunnel establishment
A spoke can establish permanent tunnels to any number of hubs. Hubs in an ADVPN domain must
establish permanent tunnels.
Figure 145 shows the tunnel establishment process:
1. The initiator originates a tunnel establishment request.
To establish a hub-spoke tunnel:
The spoke checks whether a tunnel to each hub exists. If not, the spoke sends a tunnel
establishment request to the hub.
Server
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