In the area of data link layer protocol and algorithms our group has been focusing on developing a variety of novel single and multiple wavelength bandwidth allocation protocols for GPONs, long-reach PONs and WDM-PONs to resourcefully and dynamically arrange the bandwidth among subscribers.
In view of recent developments on energy efficient PONs our group is focusing on Green Networks in developing energy efficient layer-2 solutions deployed over NG-PON1 and NG-PON2. The research target in this area is to design and implement energy efficient protocols and algorithms while doing minimum modifications to the existing network protocols and at the same time improving the network performance by factor of 100 from existing solutions.
This research program is geared towards improving the performance of NG-PONs through the development of advanced dynamic bandwidth allocation (DBA) protocols. In particular, the aim is to enhance the quality of service (QoS) offered by standard PONs by means of providing subscribers with service level agreement (SLA) to fulfil applications and associated bandwidth requirements on demand. A novel service and bandwidth focused DBA protocol is developed for standard time division multiplexing (TDM), gigabit-capable PONs (GPONs) by flexibly assigning a guaranteed minimum bandwidth to each optical network unit (ONU), terminated at subscribers premises.
To overcome the inevitably limited communication capacity of single wavelength TDM protocols and with the transportation of the ever increasing, time-sensitive, multi-media services in mind, a novel multi-wavelength DBA protocol is then developed to be applied to a wavelength division multiplexing–PON (WDM-PON).
Layer-2 protocols and algorithms for OFDMA-PONs (as part of our active involvement in European FP7 ACCORDANCE project) have also been one of the main focuses of our group. New medium access control protocols and frame formats have been developed, exhibiting hybrid OFDMA/time division multiple access scheduling, for capacity enhancement and granular bandwidth allocation. The developed sequential dynamic subcarrier allocation algorithms allow the network optical line terminal to grant the optical network units (ONUs) bandwidth using both status and non-status based reporting.
In addition, IP backhauling of LTE-A base stations over developed OFDMA-PON was investigated from layer-2 perspective in order to provide an effective mapping mechanism between optical and wireless queues for QoS provisioning.
Following recent developments in NG-PON2, where the FSAN meeting in April 2012 selected the time and wavelength division multiplexed passive optical network (TWDM-PON) as a primary solution, our group has been focusing on proposing a new protocol and algorithms towards this direction to enable multi-wavelength operation over splitter-PON.
To that extent, a novel advanced dynamic multi-wavelength (DMW) protocols and algorithms have been developed to increase the network upstream bandwidth and introduce a multiple service levels to a FTTH-based TWDM-PONs.