Subscriber Access Operation Flow

The subscriber access feature requires that a subscriber (for example, a DHCP client) send a discover message to the router interface to initialize dynamic configuration of that interface.

Figure 2 shows the flow of operations that occur when the router is using DHCP relay to enable access for a subscriber.

Figure 2: Subscriber Access Operation Flow

The following general sequence occurs during access configuration for a DHCP client:

1. The client issues a DHCP discover message.
2. The router DHCP component recognizes the DHCP message and adds the client to the router session database.
3. If configured, the router issues an authorization request to the RADIUS server.
4. The DHCP server issues an IP address for the client. When the address is relayed, the address is added to the router session database.
5. RADIUS issues an authorization response to the router.
6. The router adds RADIUS authorization information to the router session database.
7. The router combines the dynamic profile with the RADIUS authorization information.
8. The router alerts all internal applications involved with the subscriber access (for example, routing protocols, dynamic firewall, and dynamic Class of Service).
9. The router passes the message through to the DHCP server.
10. The router DHCP component sends an acknowledgement back to the client.

The subscriber now has access to the network and the authorized service.

Related Topics

• Subscriber Access Overview
• Configuring Subscriber Access