Cisco Systems OL-4387-02 Service Selection Methods, PPP Terminated Aggregation, PTA-Multidomain

C H A P T E R 5

Service Selection Methods

The Cisco 10000 series router supports the following service selection methods:

•PPP Terminated Aggregation, page 5-1

•PTA-Multidomain, page 5-1

•Web Service Selection, page 5-2

This chapter describes the service selection methods.

PPPTerminated Aggregation

PPPterminated aggregation (PTA) is a PPP selection method in which service selection is based on a structured domain name (for example, username@service.com). PTA terminates the PPP session into a single routing domain. Users can only access one service and users do not have access to the default network or SESM.

The PTA-MD exclusion list allows you to create a set of domains that you want to exclude from

SSG processing. When a PPP user attempts to establish a PPP session using a domain that is included in the exclusion list, the traffic is treated as non-SSG traffic and is processed by Cisco IOS software. The system does not apply SSG features and processing to the traffic.

PTA-Multidomain

PTA-Multidomain (PTA-MD) is a PPP selection method in which service selection is based on a structured domain name (for example, username@service.com). PTA-MD terminates the PPP sessions into multiple IP routing domains. SSG features and processing are applied to the user traffic and users can access one or more services at a time. PTA-MD service selection supports a wholesale VPN model where each domain is isolated from the other and has the capability to support overlapping IP addresses.

The Cisco 10000 series router implements PTA-MD service selection in the following way:

•The access provider terminates the user PPP sessions and logically associates each session with a particular service.

•Network side interfaces are associated with a service. SSG binds the user session and its service to the appropriate network side interface.

•SSG binds the network side interface associated with a service to a virtual routing and forwarding (VRF) instance. All users who subscribe to that service are also bound to that same VRF. Packets to and from the user and to and from the network side interface are routed within the same VRF.

Cisco 10000 Series Router Service Selection Gateway Configuration Guide

OL-4387-02 5-1