Introduction - Cisco ASR 5000 Administration Manual
Enhanced wireless access gateway
Hide thumbs
Also See for ASR 5000:
- Administration manual (466 pages) ,
- Installation manual (294 pages) ,
- Installation procedure (8 pages)
Table of Contents
Advertisement
▀ Introduction
Introduction
Providing a consistent subscriber experience and supporting the ever exploding demand for bandwidth to provide data
services in 3G/4G networks is quickly becoming a big challenge for mobile operators. Widely prevalent Wireless Local
Area Network (WLAN) at public hotspots, private corporate networks, and so on have been viewed as providing a
viable alternative to 3G/4G radio and providing a solution to the overloading of radio networks by providing an
offloading solution. These Interworking WLAN (I-WLAN) provide subscriber access to 3G/4G networks making
services offered by operators universally available.
However, due to the inherent un-trusted nature of WLANs, the I-WLAN solution has been designed keeping security
aspects in view and so is based on IPSec. The IPSec-based solution requires a client to be installed on the UE. At this
point in the evolution of subscriber access from WLANs, the UE client has been a major stumbling block in the
deployment of I-WLANs.
On the other hand, trusted Wi-Fi networks provide a unique opportunity in converting WLANs into seamless extensions
of 3G/4G mobile networks, enabling improved subscriber experience, especially indoors which often suffers poor
cellular coverage, as subscribers are able to reach their 3G/4G services via both mobile and Wi-Fi accesses.
The Cisco® eWAG enables Wi-Fi integration into 3G mobile packet core (MPC), allowing clientless UE attached to
trusted Wireless Local Area Networks (WLANs) seamlessly access 3G services. In this case, the UE does not require a
client, it has no dependencies on the Wi-Fi architecture, and does not realize that it is connecting to a 3G network (3G
access is integrated with the normal UE-WLAN attach procedure).
The Cisco® eWAG can be configured in the following modes:
RADIUS-based eWAG — This solution is based on RADIUS accounting messages generated by the WLAN
network. Here the UE attaches to the WLAN network after authentication and acquires an IP address, and then
the Accounting-Start message generated for the UE session from WLAN network is received at eWAG to
create the corresponding 3G session with the GGSN. This means that the 3G network operator will provide the
3G IP address and the UE has already obtained a Wi-Fi IP address during WLAN attachment procedure. So the
mobility between change of access is not possible as the UE changes its location.
For more information on R-eWAG, refer to the RADIUS-based Enhanced Wireless Access Gateway Overview
chapter.
DHCP-based eWAG — This solution is based on the DHCP protocol and uses the IP address allocated by the
GGSN node for the UE attaching to the WLAN network. The IP address is maintained across the access. There
is no separate IP address space like 3G IP address and Wi-Fi IP address. D-eWAG achieves this by acting as
DHCP-Server to the Wi-Fi network and allocating the IP address to the WLAN UE directly when it tries to
attach to the WLAN network.
For more information on D-eWAG, refer to the DHCP-based Enhanced Wireless Access Gateway Overview
chapter.
▄ Cisco ASR 5000 Enhanced Wireless Access Gateway Administration Guide
12
Enhanced Wireless Access Gateway Overview
Advertisement
Table of Contents
