Cisco Cisco Packet Data Gateway (PDG) Guia De Resolução De Problemas
Understanding the Service Operation and Configuration
▀ Terminology
▄ Cisco ASR 5000 Series Packet Data Serving Node Administration Guide
OL-22939-01
Terminology
This section defines some of the terms used in this manual.
Contexts
A context is a logical grouping or mapping of configuration parameters that pertain to various physical ports, logical IP
interfaces, and services. A context can be thought of as a virtual private network (VPN).
interfaces, and services. A context can be thought of as a virtual private network (VPN).
The system supports the configuration of multiple contexts. Each is configured and operates independently from the
others. Once a context has been created, administrative users can then configure services, logical IP interfaces,
subscribers, etc.for that context. Administrative users would then bind the logical interfaces to physical ports.
others. Once a context has been created, administrative users can then configure services, logical IP interfaces,
subscribers, etc.for that context. Administrative users would then bind the logical interfaces to physical ports.
Contexts can also be assigned domain aliases, wherein if a subscriber‘s domain name matches one of the configured
alias names for that context, then that context is used.
alias names for that context, then that context is used.
Contexts on the system can be categorized as follows:
Source context: Also referred to as the ―ingress‖ context, this context provides the subscriber‘s point-of-entry in
the system. It is also the context in which services are configured. For example, in a CDMA2000 network, the
radio network containing the packet control functions (PCFs) would communicate with the system via R-P
interfaces configured within the source context as part of the PDSN service.
radio network containing the packet control functions (PCFs) would communicate with the system via R-P
interfaces configured within the source context as part of the PDSN service.
Destination context: Also referred to as the ―egress‖ context, this context is where a subscriber is provided
services (such as access to the Internet). Destination contexts are typically named after particular domains. For
example, the system‘s destination context would be configured with the interfaces facilitating subscriber data
traffic to/from the Internet, a VPN, or other PDN.
example, the system‘s destination context would be configured with the interfaces facilitating subscriber data
traffic to/from the Internet, a VPN, or other PDN.
AAA context: This context provides authorization, authentication, and accounting (AAA) functionality for
subscriber and/or administrative user sessions. The AAA context contains context-specific AAA policies, the
logical interfaces for communicating with AAA servers, and records for locally configured subscribers and/or
administrative users.
logical interfaces for communicating with AAA servers, and records for locally configured subscribers and/or
administrative users.
Important:
It is important to note that ―source,‖ ―destination,‖ and AAA functionality can optionally be
configured within the same context or be configured as separate contexts. As a general rule, however, if the carrier owns
and operates the AAA server, it is recommended that AAA functionality be configured within the source context.
Conversely, if a home network other than the carrier‘s own operates the AAA server, it is recommended that AAA
functionality be configured within the destination context. To ensure scalability, AAA functionality for subscriber
sessions should not be configured in the local .
and operates the AAA server, it is recommended that AAA functionality be configured within the source context.
Conversely, if a home network other than the carrier‘s own operates the AAA server, it is recommended that AAA
functionality be configured within the destination context. To ensure scalability, AAA functionality for subscriber
sessions should not be configured in the local .
AAA Realms
A AAA realm is the location within the AAA context where subscriber-specific templates can be defined that are
applied to subscribers who match that realm. A AAA realm is considered part of the AAA context; and the AAA
applied to subscribers who match that realm. A AAA realm is considered part of the AAA context; and the AAA