Cisco ASR 5000 Series Administration Manual page 130

▀ Example 2: Mobile IP Support Using the System as an HA
Figure 28. Call Processing When Using the system as an HA
Foreign
AAA Server
Packet Data Network
GGSN/FA
Context (Ctx.)
Interface
Service or
Configuration (Cfg.)
1. A subscriber session from the FA is received by the HA service over the Gi interface.
2. The HA service determines which context to use to provide AAA functionality for the session. This process is
described in the How the System Selects Contexts section located in the Understanding the System Operation
and Configuration chapter of the System Administration Guide.
For this example, the result of this process is that the HA service determined that AAA functionality should be
provided by the Source context.
3. The system then communicates with the Home AAA server specified in the Source context‟s AAA configuration
to authenticate the subscriber.
▄ Cisco ASR 5000 Series Gateway GPRS Support Node Administration Guide
Home
AAA Server
3 6
6
1
HA
AAA
AAA Cfg.
2
P
HA-
Gi
D
Service
N
4
Def. Sub.
5
Source Destination
Ctx. Ctx.
Local Ctx.
Mobile IP Configuration Examples
Packet Data Network
OL-22944-02