Insight on India's Telecom Market and Bandwidth Optimization Needs

As India’s mobile service providers evolve from 2G to 3G networks, the nation’s rapidly-growing telecom market is poised to require a significant increase in core bandwidth in order to handle voice traffic. After exploring the transition from 2G to 3G and the voice bandwidth requirements of each network, this article will present a next-generation bandwidth optimization solution which can help service providers in India and worldwide cost-effectively embrace this inevitable core network evolution.

 

The transition from 2G to 3G and ultimately 4G has begun; however, more than 80% of the world’s mobile subscribers still use 2G service. In India, for example, 3G service is not yet available. Therefore, the number of 2G subscribers in India and globally will continue to grow, surpassing four billion worldwide by 2012 (Figure 1).

 

 

With this network evolution on the horizon, service providers are seeking ways to prepare for and ultimately make this transition. One key step involves the core voice network evolution from a network of TDM-based mobile switching systems (MSSs) to an IP-based mobile switching center (MSC (News - Alert)) server (Figure 2).

 

In 2G networks, voice is carried through the mobile core network between MSC switches uncompressed in 64 Kbps channels. By using compression solutions, mobile operators are able to reduce core bandwidth requirements by a factor of up to 16 with minimal to no reduction in voice quality. In 3G networks, voice arrives from the access network at the mobile media gateway over A-interface or IuCS-interface links, and is then transmitted over the Northbound interface using GSM-AMR or G.711 compression. Moreover, between the media gateways, the voice traffic is carried at a compression ratio of 2.7:1. Therefore, for 2G operators who are used to 8:1 to 16:1 compression ratios, transitioning to 3G networks means a three to five time increase in the bandwidth required to carry the same amount of voice traffic.

 

To address this problem, service providers need a low cost, scalable solution that can further compress the VoIP sessions sent between the media gateways without degrading voice quality. The requirements for such a solution include but are not limited to: transparency to 3G network elements, support for IP-over-TDM and IP-over-Ethernet networks, and scalability to support small remote sites as well as larger high-capacity nodes. This solution could enable operators to maximize session bandwidth optimization, improve transmission media efficiency, preserve voice quality performance, and offer high service availability. Moreover, this solution would ideally be designed to fit transparently between media gateways, ultimately allowing 3G operators to achieve the same bandwidth reduction benefits they realized when using TDM-based compression solutions between their 2G MSSs.

 

While 3G and 4G technologies tend to dominate the mobile investment discussion, most mobile subscribers in India and worldwide are still served by 2G networks. As service providers evolve from 2G to 3G, the bandwidth required in the core voice network will increase significantly. Therefore, service providers will require a next-generation VoIP session bandwidth optimization solution which can reduce voice bandwidth in 3G networks and ideally enable them to achieve the same higher bandwidth compression ratios they could achieve utilizing 2G. Mobile operators should investigate solutions from equipment vendors that will enable them to meet these needs.