Feature Description; Ue Identity And Location Information Support; Radius Aaa Support - Cisco ASR 5000 Administration Manual

Enhanced Wireless Access Gateway Overview

Feature Description

This section presents general description of features supported by the 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
 UE Identity and Location Information Support

Bulk Statistics Support

Threshold Crossing Alerts Support

Congestion Control Support

Redundancy Support
RADIUS AAA Support
The eWAG provisions a RADIUS server, as defined in RFC 2865, which enables the 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 eWAG, refer to the Enhanced Wireless Access Gateway AAA AVP
Support appendix.
The eWAG provisions configuring one or more RADIUS clients (with corresponding authentication keys) to create a
trusted set of AAA. The eWAG discards RADIUS messages from any device that is not in the RADIUS client list. The
eWAG authenticates each RADIUS message using a configured authentication key. The 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 eWAG. Here,
Wi-Fi AAA acts as the RADIUS accounting client and eWAG as the RADIUS accounting server. eWAG extracts the
necessary attributes required to create the GTP tunnel to GGSN. eWAG resolves the APN to get the GGSN address to
which to create the GTP tunnel. In this release, the PDP context will be created with a dynamic IP address.
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Cisco ASR 5000 Enhanced Wireless Access Gateway Administration Guide ▄
Feature Description ▀
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