Cisco 3825 Software Configuration Guide - Page 13

Chapter 1 Overview of the Cisco 3825 Mobile Wireless Edge Router Introduction Another equally important benefit is that substantial excess capacity is now available in the existing RAN backhaul network. The operator can reallocate this recovered bandwidth to carry traffic from other radios, such as UMTS Node Bs, GPRS, EDGE, 1xEV-DO, PWLANs, and other data overlays. This capability reduces the deployment and operating costs for new technologies, since the operator avoids the up-front and recurring costs of supplementing backhaul capacity. It also accelerates time to revenue from deployments of new radio technologies since there is no need for the operator to wait for additional microwave licenses or leased lines to be supplied. Compliance with 3GPP2 and 3GPP R5 and R6 transport standards is another appealing aspect of Cisco's RAN-O solution. Cisco converts today's CDMA transport networks into 3GPP2-compliant IP RAN transport networks, and GSM and R4/R99 UMTS transport networks into R5/R6 IP RAN transport networks now-and adds multi-radio backhaul compression as well. This means operators can enjoy the benefits of IP transport in their CDMA, GSM, and R4/R99 UMTS RANs today. Figure 1-2 Example of Cisco 3825 Router in a GSM Abis and UMTS Iub Optimization over IP GSM BTS IP-PBX BSC TDM 100Base-T PWLAN WCDMA-TDD WiMAX (802.16/20) ATM UMTS Node B (R4/R99) HSDPA Cisco MWR T1/E1 Cisco ONS 15454 Optimized Abis/lub over IP IP UMTS Node B (RS/R6) Mobile IP/FA VoIP Content Caching Multi VPN IP Multicasting QoS PPP DHCP Routing TDM IP-PBX ATM IP RNC Cisco Mobile Exchange 203232 Cell Site Access Network BSC/RNC Site Mobile Internet Edge Cisco GSM Abis Optimization over IP The Cisco GSM Abis Optimization over IP technology improves T1/E1 bandwidth efficiency by 33% to 50%, corresponding to a GSM voice call capacity gain of 50-100% per T1/E1, depending on the nature of the traffic on the interface. In a GSM RAN, the interface between the BTS and BSC is a 3GPP reference interface called the Abis interface. The physical trunk connecting a BTS and BSC is typically a T1 or E1 circuit, and carries 24 (T1) or 32 (E1) separate 64 kbps DS0 channels. One or two of these DS0 channels is used to carry control and signaling traffic, while the remainder are used to carry bearer traffic-voice and data from mobile OL-15667-03 Cisco 3825 Mobile Wireless Edge Router Software Configuration Guide 1-3