10 Gbit/s bit interleaving CDR for low-power PON

A novel, low power, downstream clock and data recovery (CDR)- decimator architecture is proposed for next generation, energy efficient 10 Gbit/s optical network units (ONUs). The architecture employs a new time division multiplexing bit-interleaving downstream concept for passive optical networks (Bi-PON) allowing early decimation of the incoming data and lowering of the processing speed to the user rate of the ONU, thus reducing the power consumption significantly

Energy efficient DBA algorithms for TWDM-PONs

Energy efficiency is of a vital significance in the design of next generation time and wavelength division multiplexed passive optical networks (TWDM-PONs). In this paper, we first review strategies to save energy in TWDM-PONs using the state-of-the-art dynamic bandwidth allocation (DBA) algorithms. The DBA algorithms should not only minimize energy consumption but should impose a minimal penalty on delay performance. In this context, mainly two DBA design paradigms can be exploited: offline and online. After reviewing the performance of various design paradigms, we propose an optimal algorithm, which minimizes the energy consumption at both the OLT and the ONUs, by combining the energy efficiency due to sleep modes and the load dependent use of transceivers at the OLT. Due to this, the average energy consumption is reduced to 31%

Energy Efficient Network Function Virtualisation in 5G Networks

Once the dust settled around 4G, 5G mobile networks become the buzz word in the world of communication systems. The recent surge of bandwidth-greedy applications and the proliferation of smart phones and other wireless connected devices has led to an enormous increase in mobile traffic. Therefore, 5G networks have to deal with a huge number of connected devices of different types and applications, including devices running life-critical applications, and facilitate access to mobile resources easily. Therefore given the increase in traffic and number of connected devices, intelligent and energy efficient architectures are needed to adequately and sustainably meet these requirements. In this thesis network function virtualisation is investigated as a promising paradigm that can contribute to energy consumption reduction in 5G networks. The work carried out in this thesis considers the energy efficiency mainly in terms of processing power consumption and network power consumption. Furthermore, it considers the energy consumption reduction that can be achieved by optimising the locations of virtual machines running the mobile 5G network functions. It also evaluates the consolidation and pooling of the mobile resources. A framework was introduced to virtualise the mobile core network functions and baseband processing functions. Mixed integer linear programming optimisation models and heuristics were developed minimise the total power consumption. The impact of virtualisation in the 5G front haul and back haul passive optical network was investigated by developing MILP models to optimise the location of virtual machines. A further consideration is caching the contents close to the user and its impact on the total power consumption. The impact of a number of factor on the power consumption were investigated such as the total number of active users, the backhaul to the fronthaul traffic ratio, reduction/expansion in the traffic due to baseband processing, and the communication between virtual machines. Finally, the integration of network function virtualisation and content caching were introduced and their impact on improving the energy efficiency was investigated

An FPGA implementation of a sleep enabled PON system

Owing to the growing demand for bandwidth-hungry video-on-demand applications, Passive Optical Network (PON) has been widely considered as one of the most promising solutions for broadband access. Environmental concerns motivated network designers to lower energy consumption of optical access networks. A well-known approach to reduce energy consumption is to allow network elements to switch to the sleep mode. In this framework, an improved Optical network Unit (ONU) architecture in TDM-PON is proposed to reduce the handover time of status switching. Energy-saving performances of current and improved architectures are compared in different scenarios. The simulation results show that by applying a proper sleep mode mechanism, the improved architecture can effectively reduce the ONU energy consumption. We further implement the cycle sleep scheme on a multi-ONU testbed based on the improved ONU architecture. The experimental results have substantiated the viability of the improved ONU architecture