Radius Proxy - Cisco ASR 5000 series Product Overview

▀ Service Modes

RADIUS Proxy

In the event that the Access Gateway is incapable of sending two separate RADIUS Start message, the IPSG can be
configured as a RADIUS Proxy. As shown in the following figure, the IPSG receives an IPSG RADIUS proxy Access
request, then generates the Authentication and Accounting requests to the AAA Server.
Figure 114. IPSG Message/Data Flow (RADIUS Server Mode - RADIUS Proxy)
RADIUS Snoop Mode
When configured in RADIUS snoop mode, the IPSG simply inspects RADIUS accounting request packets sent to a
RADIUS server through the IPSG.
As shown in the following figure, the IPSG has three reference points: sn, si, and sr. The sn interface transmits/receives
data packets to/from the access gateway (GGSN, HA, PDSN, etc.). The si interface transmits/receives data packets
to/from the Internet or a packet data network. The sr interface receives RADIUS accounting requests from the access
gateway. The system inspects the accounting request packets and extracts information to be used to determine the
appropriate service(s) to apply to the flow. Information is not extracted from the RADIUS accounting responses so they
are sent directly to the access gateway by the RADIUS Server, but can also be sent back through the IPSG.
▄ Cisco ASR 5000 Series Product Overview
IP Services Gateway Overview
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