The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Performance problems, which can stem from different system components, such as network, memory, and storage devices, are difficult to diagnose and isolate in a cluster file system. In this paper, we present an online performance anomaly detector which is able to efficiently detect performance anomaly and accurately identify the faulty sources in a system node of a cluster file system. Our method exploits...
Dynamic resource provisioning for virtualized server applications is integral to achieve efficient cloud and green computing. In server applications unpredicted workload changes occur frequently. Resource adaptation of the virtual hosts should dynamically scale to the updated demands (cloud computing) as well as co-locate applications to save on energy consumption (green computing). Most importantly,...
In this paper, we study the delay performance of wireless network considering different resource allocation schemes with single-hop traffic. Existing works studying the delay performance only consider a given resource allocation scheme, either multi-channel system (sharing bandwidth) or time slotted system (sharing time). The fundamental question ignored is which type of resource allocation scheme...
Considering convergence of vast and different technologies in new generation networks, the required quality of service is the key success factor. The site implementation according to special benchmarking (TPC-W), to achieve the acceptable service performance may be offered in a cost effective manner, is very complicated. In this paper a mathematical method will be introduced to help providers to make...
Pub/Sub systems permit users to submit subscriptions and notify interested users of the events detected in a distributed way. Moving a Pub/Sub system to a cloud infrastructure is for high performance and scalability. This paper describes how to migrate two Pub/Sub systems i.e. PADRES and Once Pub Sub to Xen Cloud Platform, especially proposes black-box method, grey-box method and white-box method...
Balancing communication workloads is a perennial performance issue in the area of Distributed Virtual Environments (DVE). The stringent time constraints of Multiplayer Online Games (MOG) complicate efforts to effectively distribute the networking load amongst servers. This issue becomes ever more exacting, when we move towards a fully Peer-to-peer virtual world (P2P-VE). We are consequently forced...
Providing quality-of-service (QoS) for concurrent tasks in many-core architectures is becoming important, especially for real-time applications. QoS support for on-chip shared resources (such as shared cache, bus, and memory controllers)in chip-multiprocessors has been investigated in recent years. Unlike other shared resources, network-on-chip (NoC) does not typically have central arbitration of...
We consider multihomed scalable video streaming, where videos are transmitted by a single server to multiple clients over heterogeneous access networks. The specific problem that we address is to determine which video packets to transmit over each network, in order to minimize a cost function of the expected video distortion at the clients. We present a network model and a video model that capture...
Many different accounting systems currently exist for the European Grids and for other distributed systems in general. Even though they often share equivalent technical approaches, concerning accounting metrics and batch-system log access, there are lots of different data formats, accounting-database layouts, communication- and implementation details that hinder a consistent and comprehensive accounting...
Performance and scalability of service-oriented applications, such as Web service compositions or business processes, depend on the dynamically bound services. In order to handle an increasing number of clients, load-balancing techniques are important. In this paper we assume the presence of multiple functionally equivalent services and explore different load-balancing algorithms to dynamically select...
Load balancing is a key component of P2P network. In this paper, we present a new load balancing scheme for Chord system, called dynamic group-based duplications scheme (DGDS). Firstly, we divide Chord ring into several continuous groups, in which light-loaded peers share the load of overloaded peers. Secondly, DGDS computes out how many duplications are required to lighten the load of overloaded...
In this paper we face the challenging issue of defining and implementing an effective law for load balancing in Content Delivery Networks. We base our proposal on a formal study of a CDN system, carried out through the exploitation of a fluid flow model characterization of the network of servers. Starting from such characterization, we derive and prove a lemma about the network queues equilibrium...
In this paper, we present a framework for performance modeling of virtual collaborative environments (VCE). Our model could be used as benchmarking tool for assessing the quality of experience of participants in a virtual environment. Our framework is designed to assess Second Life type of environments but could easily be extended to any kind of virtual worlds. We examine the case of users communicating...
Cloud computing often uses the multi-tenancy architecture where tenants share system software. To support dynamically increasing demands from multi-tenants, the cloud service providers have to duplicate computing resources to cope with the fluctuation of requests from tenants. This is currently handled by virtualization and duplication at the application level in the existing cloud environment, such...
The numbers of smart phone users and related applications are growing rapidly, and applications continue to become more data-intensive. In the cloud based service for smart phone, if user demand on virtual machines exceeds the hardware capacity of the server, the server incurs an overload and bottleneck, network delay, latency, and packet loss rate are increased in 3G and Wi-Fi connections. Therefore,...
The recent emergence of, cloud computing is making the, vision, of, utility computing, realizable, i.e., computing resources and services from a cloud can be delivered, utilized, and paid for in the same fashion as utilities like water or electricity. Current, cloud service providers have taken some steps towards supporting the true, pay-as-you-go or a utility-like pricing model, and current research...
Virtualization provides an effective management in server consolidation. The transparence enables different kinds of servers running in the same platform, making full use of hardware resource. However, virtualization introduces two-level schedulers: one from Guest OS, where the tasks are scheduled to virtual CPUs (VCPUs), the other from the virtual machine monitor (VMM), where VCPUs are scheduled...
In this paper, we propose a load balancing scheme for heterogeneous multiple AS (Application Server) system in IMS (IP Multimedia Subsystem) network. In IMS network, S-CSCF (Serving Call Session Control Function) utilizes iFC(initial Filter Criterion) downloaded by HSS(Home Subscriber Server) and generates service trigger through the SIP message. To perform load balancing among multiple AS with different...
Recently, Qin et al. proposed a three-tier Peer-to-Peer (P2P) architecture for real-time file search in distributed networks [8]. In this architecture, indices of files held by the user peers in the bottom layer are stored at the super-peers in the middle layer, and the correlation of those two bottom layers is controlled by the central server(s) in the top layer using the notion of tags. In Qin's...
The growing demand of mobile wireless internet access has prompted rapid growth of wireless data services. The key issue of wireless cloud is to provide complex services by using the available resources within reasonable cost. Accompanying the emergence of integrated wireless and mobile networks (e.g. WLAN, 3G/4G net), it makes a challenge of networks as service to supporting the complete lifecycle...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.