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Cisco 3825 Mobile Wireless Edge Router Software Configuration Guide
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Overview of the Cisco 3825 Mobile Wireless Edge Router
The Cisco 3825 Mobile Wireless Edge Router is a networking platform optimized for use in mobile
wireless networks; specifically designed to be used at the cell site edge as a part of a 2G, 3G or 4G Radio
Access Network (RAN). The Cisco 3825 Mobile Wireless Edge Router is a general purpose router
platform specializing in 2/2.5G Global System for Mobile Communication (GSM) and 3G Universal
Mobile Telecommunication System (UMTS) RAN backhaul transport and optimization.
The Cisco 3825 router offers high performance at a low cost while meeting the critical requirements for
deployment in cell sites, including small size, high availability, and
DC input power flexibility.
This chapter includes the following sections:
• Introduction, page 1-1
• Cisco IOS Software Features, page 1-6
• MIB Support, page 1-10
• Limitations and Restrictions, page 1-11
• New Features in Cisco IOS Release 12.4(16)MR2, page 1-13
• New Features in Cisco IOS Release 12.4(16)MR1, page 1-13
• New Features in Cisco IOS Release 12.4(16)MR, page 1-27

Introduction

A typical RAN is composed of thousands of Base Transceiver Stations (BTSs)/Node Bs, hundreds of
Base Station Controllers/Radio Network Controllers (BSCs/RNCs), and several Mobile Switching
Centers (MSCs). The BTSs/Node Bs and BSCs/RNCs are often separated by large geographic distances,
with the BTSs/Node Bs located in cell sites uniformly distributed thr oughout a region, and the BSCs,
RNCs, and MSCs located at suitably chosen central offices (COs) and/or M obile Telephone Switching
Offices (MTSOs). The traffic generated by a BTS/Node B is transported to the corresponding BSC/RNC
across a network, referred to as the backhaul network, whic h is often a hub-and-spoke topology with
hundreds of BTSs/Node Bs connected to a given BSC/RNC by point-to-point time-division multiplexing
(TDM) trunks. These TDM trunks may be leased line T1/E1s or their logical equivalents, such as
microwave links or satellite channels. The interface between the BTS and BSC in GSM and Code