Feature Description; R-Ewag-Wlc/Wi-Fi Aaa Interface - Cisco ASR 5000 Administration Manual

RADIUS-based Enhanced Wireless Access Gateway Overview

Feature Description

This section presents general description of features supported by the R-eWAG.
 RADIUS AAA Support

Differentiated Services Code Point Marking

Access Point Name Selection

Quality of Service Profile Selection

GGSN Selection

GGSN Failover Case

Network Address Translation and Application Level Gateway Support

Virtual APN Support

Offline Charging Support

UE Identity and Location Information Support

Lawful Intercept Support

Bulk Statistics Support

Threshold Crossing Alerts Support

Congestion Control Support

Redundancy Support

R-eWAG-WLC/Wi-Fi AAA Interface

The R-eWAG provisions a RADIUS server, as defined in RFC 2865, which enables the R-eWAG to act as a RADIUS
accounting server supporting receiving and responding to RADIUS accounting messages as defined in RFC 2866.
For the list of RADIUS attributes supported by R-eWAG, refer to the RADIUS-based Enhanced Wireless Access
Gateway AAA AVP Support appendix.
The R-eWAG provisions configuring one or more RADIUS clients (with corresponding authentication keys) to create a
trusted set of AAA. The R-eWAG discards RADIUS messages from any device that is not in the RADIUS client list.
The R-eWAG authenticates each RADIUS message using a configured authentication key. The R-eWAG creates a new
PDP context (for a subscriber session) upon receiving a valid RADIUS Accounting Start Request.
No 3GPP interface has been defined between WLAN and MPC. Therefore, RADIUS messages generated by core Wi-Fi
network (for example, from WLAN AAA client (WLC or ISG)) are used to provide WLAN session information (Wi-Fi
IP address of UE) to MPC and set up access side association. For this, RADIUS accounting messages
(Start/Interim/Stop) are used.
Many attributes required by MPC (IMSI, MSISDN, APN, Charging-Characteristics, and others) are not inherent in
WLAN access interactions. So, these have to be populated by a WLAN network entity after obtaining it from the MPC.
This enrichment is done by the Wi-Fi AAA. The Wi-Fi AAA interacts with the MPC AAA to obtain these attributes
when UE authentication (EAP over 802.1x) is initiated during initial WLAN attach. Wi-Fi AAA caches these attributes.
After successful authentication and session establishment, WLAN AAA-client (WLC or ISG) generates Accounting-
Start message. This message is proxied by Wi-Fi AAA, enriched with MPC-related attributes, and sent to R-eWAG.
Cisco ASR 5000 Enhanced Wireless Access Gateway Administration Guide ▄
Feature Description ▀
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