Energy-efficient Phase-based Cache Tuning for Multimedia Applications in Embedded Systems

Abstract-The proliferation of multimedia applications in embedded systems has led to a research focus on optimizing the energy consumption of these applications without significantly degrading the execution time and adhering to data processing deadline constraints. To maximize optimization potential, phasebased tuning methodologies specialize system configurations to different phases of application execution with respect to design constraints. Multimedia applications are ideal candidates for phase-based tuning since these applications exhibit variable execution characteristics. In this paper, we propose a phasebased tuning methodology for multimedia applications that leverages application characteristics to determine the best cache configurations for different phases of execution. Results reveal that phase-based tuning for multimedia applications determines cache configurations within 1% of the optimal on average and yields an average energy delay product savings of 29%

Energy and Thermal-Aware Video Coding via Encoder/Decoder Workload Balancing

Even with consistent advances in storage and transmission capacity, video coding and compression are essential components of multimedia services. Traditional video coding paradigms result in excessive computation at either the encoder or decoder. However, several recent papers have proposed a hybrid PVC/DVC (Predictive/ Distributed Video Coding) codec which shares the video coding workload. In this paper, we propose a controller for such hybrid coders that considers energy and temperature to dynamically split the coding workload of a system comprised of one encoder and one decoder. Results show that the proposed controller results in more balanced energy utilization, improving overall system lifetime and reducing operating temperatures when compared to strictly PVC and DVC systems

Analyses and design of a new integrated mobile SIP proxy to enhance the scalability in mobile network operators

The emergence of the two new technologies, namely Software Defined Network (SDN) and Network Function Virtualization (NFV) have radically changed the development of computer network fun etions and the evolution of mobile network operators (MN Os) infrastructures. The se two technologies bring to MN Os the promises of reducing costs, enhancing network flexibility and scalability to handle the growth in the number of mobile users and the need to extend its coverage to rural areas. The aim of this thesis 1s to exploit the advantages of the NFV concept to support the implementation of full y integrated solution with an external Session Initial Protocol (SIP) proxy application to enhance the scalability in MN Os. The proposed solution offers a hosted SIP proxy application installed on a virtual machine (VM) environment. The SIP proxy provides full Private Branch Exchange (PBX) and Switch (SW) functionality with Interactive Voice Response (IVR) capabilities. It maximizes the capacity in the existing servers and value-added services (VAS) data centers within the MNOs. The proposed solution enhances the usage of the existing bandwidth by using the unlicensed radio frequency (RF) spectrum bandwidth instead of the licensed RF spectrum to support a larger number of smartphones and data plans. In the initial experimental testbed, TeleFinity IP PBX, which is an external SIP proxy, 1s deployed on a virtual platform and integrated with the mobile network. The integration 1s realized by establishing a point to point protocol (PPP) SIP trunk connection between TeleFinity IP PBX and the Gateway Mobile Switch Center (GMSC). Severa! Testing scenarios were carried out over a local area network (LAN) and a wide area network (W AN) using different voice codees: G.711 u-law, G. 723, and G. 729 to validate the voice cali quality offered by the proposed solution. The Network analyzer software solutions: 1) Startrinity SIP tester, 2) Commview and 3) Resource Monitor are used to measure severa! Quality of Service (QoS) metrics. These include voice jitter, delay, packet Joss, and MOS. This procedure ensures that the proposed solution can handle voice communications with acceptable quality compared to LTE standards

Quality-aware performance analysis for multimedia MPSoC platforms

Ph.DDOCTOR OF PHILOSOPH