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Scalable Video Coding is one of the layered video coding method, which codes the video into different temporal, spatial and quality scalability levels. It allows partial removal of the scalable video levels to provide good QoE/QoS in a resource constrained environment. In a heterogeneous environment of devices and network technology, resources vary from device to device and one technology to another...
High Performance Computing(HPC) applications are highly optimized to maximize allocated resources for the job such as compute resources, memory and storage. Optimal performance for MPI applications requires the best possible affinity across all the allocated resources. Typically, setting process affinity to compute resources is well defined, i.e MPI processes on a compute node have processor affinity...
This paper proposes a new congestion control method based on a hop-by-hop rate control in named data networking (NDN). The proposed method suppresses the excessive reduction of Interest sending rate due to continuous negative acknowledgement (NACK) packets caused by the propagation delay. The proposed method limits the rate reduction to once per congestion. The point of our method is not to change...
GPU accelerators have successfully established themselves in modern HPC clusters due to their high performance and energy efficiency. To increase the GPU computational power in a cluster node and tackle larger problems, multi-GPU nodes have become the platform of choice for scientific applications. In a multi-GPU node, GPU devices are interconnected together via different communication channels. Thus,...
The recent advent of stacked die memory and logic technologies has lead to a resurgence in research associated with fundamental architectural techniques. Many architecture research projects begin with ample simulation of the target theoretical functions and approach. However, the logical and physical nature three-dimensional stacked devices, such as the Hybrid Memory Cube (HMC) specification, fundamentally...
This paper presents a reasoning-based approach to analog circuit synthesis using ordered node clustering representations (ONCR) to describe alternative circuit features and symbolic circuit comparison to characterize performance tradeoffs of synthesized solutions. Case studies illustrate application of the proposed methods to topology selection and refinement.
In order to cope with the expected increase in traffic demand, the large-scale deployment of Small Cells (SC) becomes a cost-efficient way to realize the foreseen capacity explosion in the near future. In this paper we investigate, for a particular forecast in the 2020, what are the requirements in terms of capacity per area unit and how SC densification along with other design criteria can fulfill...
This paper presents a design methodology for low-distortions (feed-forward) Delta-Sigma (ΔΣ) modulators topologies used in next generations wireless applications. Thus, optimized folded cascode OTA and telescopic OTA gain-boosting are selected to implement the switched capacitor (SC) integrator. First, a second order ΔΣ modulator is implemented for 2MHz bandwidth. Second, a 2–2 cascaded ΔΣ modulator...
In the provisioning of Broadband Television (BTV) services, user call blocking probability (CBP) denotes the ratio of failed user requests, which is one of the most important metrics on BTV quality of experience (QoE). This paper aims to evaluate and further to decrease the CBP of BTV services in networks with tree topology. At first, we analyze a currently typical BTV delivery network architecture,...
In current vehicles, a large number of control units are connected by several automotive specific communication buses, facilitating innovative distributed applications. At the same time, computers and entertainment devices use IP and commodity communications technology like Ethernet to connect to the Internet, allowing for innovative solutions and maintaining fast innovation cycles. Today, one can...
Peer-assisted content distribution technologies have been attracting attention. By using not only server resources but also the resources of end hosts (i.e., peers), we can reduce the offered load on servers as well as utilization of the access bandwidth of the servers. However, offered traffi to the network may increase because the traffi exchanged between peers passes across the network. Specificall,...
New service providers, completely separated from the Internet Service Providers (ISP), are growing today in the Internet scenario to create new multimedia services through the P2P approach. These providers are manifesting great interest not only for classical multimedia applications, like video streaming and video on demand, but also for other applications, like for example video-conferencing, multi-party...
Although distributed computing over a network of computers has become a reality; its success mainly depends on the performance of the underlying topology. The number of users may grow way beyond the number for which the physical topology was originally designed for, resulting in performance degradation. In such situation, the redesign of network topology is an essential scheme to improve the performance...
We compare the information retrieval performance of a network based on nodes with layer 3 and the same network based on nodes with layer 3 and 7. We begin to analyse a simple case (chain of proxies) and generalize this case in a multiline network of proxies. In this way we create a simple formulation to evaluate the gain of layer 7 (caching) with respect to the layer 3 (routing), by taking into account...
Many current parallel computers are built around a torus interconnection network. Machines from Cray, HP, and IBM, among others, make use of this topology. In terms of topological advantages, square (2D) or cubic (3D) tori would be the topologies of choice. However, for different practical reasons, 2D and 3D tori with different number of nodes per dimension have been used. These mixed-radix topologies...
The active queue management in Internet routers exploits the idea that an incoming packet can be dropped by the router even if there is some available buffering space in the router. Therefore, the router can send congestion signals to TCP before the actual congestion occurs, preventing queues and delays from growing too high. Many active queue management algorithms has been proposed till now. Unfortunately,...
ClearSpeed's CSX600 that consists of 96 Processing Elements (PEs) employs a one-dimensional array topology for a simple SIMD processing. To clearly show the performance factors and practical issues of NoCs in an existing modern many-core SIMD system, this paper measures and analyzes NoCs of CSX600 called Swazzle and ClearConnect. Evaluation and analysis results show that the sending and receiving...
New system-on-chip (SoC) design techniques are necessary to address the communication requirements for future SoC. The currently used bus-centered approach becomes an inappropriate choice because of its limitation as a shared medium that restricts the scalability of the communication architecture. Also, long bus wires result in performance degradation due to the increased capacitive load. The long...
To recover link failure on resilient packet ring (RPR) networks, IEEE 802.17 working group defines two protection mechanisms, steering and wrapping, which can restore a failed network in less than 50 ms. In this study, we focus on the RPR protection mechanisms and the properties of the three different traffic classes defined in RPR for the two mechanisms by simulation. We find that the frame delay...
Significant theoretical research was done on interconnect topologies and topology aware mapping for parallel computers in the 80s. With the deployment of virtual cut-through, wormhole routing and faster interconnects, message latencies reduced and research in the area died down. This paper presents a study showing that with the emergence of very large supercomputers, typically connected as a 3D torus...
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