Ethernet a must for mobile backhaul

The global industry alliance of organisations from all sectors of the telecoms industry has unveiled its Carrier Ethernet for Mobile Backhaul Implementation Agreement (MBIA), which lays out how to apply existing MEF specifications and industry standards to meet the increasing demands for mobile data and other high bandwidth applications.

The growing adoption of 3G services, and the wide scale rollout of new 4G technologies, means that the need for significant amounts of network capacity at the back end is only going to accelerate.

Phil Tilley, vice president of marketing for the IP division at Alcatel-Lucent, a member of the MEF, explained that there have been fears about moving to Carrier Ethernet for mobile backhaul.

These have primarily been around technical concerns such as availability, management, synchronisation and scalability, but Tilley believes that these have all been addressed, paving the way for wide-scale rollout of the technology.

"The questions about the use and implementation of Carrier Ethernet are no longer questions," he said.

Michael Howard, an industry analyst at Infonetics Research, maintains that Ethernet is the only viable and cost-effective option for next-generation mobile backhaul networks.

"When you take into account the popularity of the iPhone and its clones, plus a new wave of mobile devices including computer dongles, it is not difficult to see why the operators are under pressure to deliver a lot more bandwidth in highly competitive markets," he said.

"Legacy Time-Division Multiplexing (TDM) and Asynchronous Transfer Mode (ATM) backhaul transport services cannot match the scalability, much lower cost-per-bit, and other packet advantages of Carrier Ethernet."

Recent research from Infonetics predicts that Ethernet backhaul, be it over copper, fibre or microwave, will add over a million new or converted connections between 2009 and 2011 worldwide.

Operators usually turn to E1 or T1 lines for their mobile backhaul networks, relying on TDM and ATM technologies to deliver mobile voice, data and video broadband applications.

However, considering the growth rate of these services, this is not sustainable in the long term, further highlighting the need to implement Carrier Ethernet as it is optimised for packet data traffic and easily deployed over a multitude of transport media.

"By specifying what the service looks like, it doesn't matter what the access technology is, be it fibre, copper or microwave," said Tilley.

The tight performance requirements of mobile networks, particularly around the synchronisation between base stations to ensure smooth hand-offs between them, means that extra specifications are required compared to other Ethernet networks, which can operate asynchronously.

The MEF has identified these specific requirements, and the MBIA advises service providers on how to implement Carrier Ethernet successfully and cost-effectively for mobile backhaul.

It also aims to address performance and quality of service parameters, synchronisation options, and recovery and protection mechanisms.

The MBIA also includes recommendations for the network design, architecture and operation of packet-based mobile backhaul networks, and is designed to facilitate the deployment of profitable, data-driven mobile services by explaining the benefits and technical implementation details.

"A recent edition of Heavy Reading's Ethernet Backhaul Quarterly Market Tracker service suggests that most cellular network operators are initially looking at a self-build strategy for their transition to Ethernet backhaul," said Patrick Donegan, senior analyst at telecoms research firm Heavy Reading.

"This implementation agreement will not only help them, but present an opportunity for wireline operators to offset their revenue erosion. Investment in Ethernet backhaul services is a chance to use spare capacity and reach a growing market, as BT has done with its Vodafone UK agreement.

"The multi-year contract uses BT's 21st Century Network-enabled Ethernet service, offering backhaul speeds of up to 60Mbit/s, and allows Vodafone UK to avoid capital investment risk while benefiting from the economies of scale and national reach BT Wholesale offers."