As end-user demand for high-bandwidth services continues to escalate, so does the focus on energy efficiency, a smaller carbon footprint and eco-sustainability. In order to meet these challenges, wireline and wireless service providers must evolve their networks to a next-generation, all-IP multiservice infrastructure that is fully converged, optimized and scalable, according to telecom leader Alcatel-Lucent (News - Alert).
As part of the GreenTouch initiative – which is focused on improving the energy efficiency of Information and Communications Technology (ICT) networks – Alcatel-Lucent Bell Labs (News - Alert) researchers invented the bit interleaving passive optical network (BIPON) protocol for time division multiplexing (TDM) passive optical networks (PONs), the most commonly used fiber access technology.
The bit interleaving protocol reduces energy consumption in the optical network units (ONUs) by reducing clock speed requirements, data processing requirements, voltage requirements and memory requirements, as described in the recent Alcatel-Lucent TechZine article, “BIPON: A More Energy-efficient TDM PON."
“With the bit interleaving protocol, only the data intended for the ONU is sampled (also known as decimation). That means the high clock speed required to handle the incoming PON line rate is needed only for a very short period of time during clock recovery and the decimation process,” the article explained. This also means there is no longer a need for so-called massive parallel processing because further processing is applied only to target user data, which is typically only a small fraction of the total data available on the line, according to Alcatel-Lucent.
When this energy-intensive processing is complete, 97 percent to 99 percent of the original bits are dropped because they are intended for other ONUs on the passive optical network.
Reducing energy consumption in ONUs is a critical step toward lowering the overall energy consumption of communications networks – and progress has already been made, according to Alcatel-Lucent. However, as Bell Labs’ research confirms, there is more that can be done to reduce energy consumption in ONUs.
When implemented, the Alcatel-Lucent BIPON design can combine the bit interleaving protocol with sleep mode, which leads to further energy savings. Furthermore, the Alcatel-Lucent High Leverage Network (HLN) architecture can reduce total cost of ownership by employing fewer devices to do more with less, offering an eco-sustainable strategy choice for service providers.
By 2015, Alcatel-Lucent officials said the goal of the GreenTouch initiative is to deliver the architecture and roadmap needed to increase network energy efficiency by a factor of 1,000 from current levels.
Edited by Peter Bernstein