2,635 research outputs found
Towards Autonomic Service Provisioning Systems
This paper discusses our experience in building SPIRE, an autonomic system
for service provision. The architecture consists of a set of hosted Web
Services subject to QoS constraints, and a certain number of servers used to
run session-based traffic. Customers pay for having their jobs run, but require
in turn certain quality guarantees: there are different SLAs specifying charges
for running jobs and penalties for failing to meet promised performance
metrics. The system is driven by an utility function, aiming at optimizing the
average earned revenue per unit time. Demand and performance statistics are
collected, while traffic parameters are estimated in order to make dynamic
decisions concerning server allocation and admission control. Different utility
functions are introduced and a number of experiments aiming at testing their
performance are discussed. Results show that revenues can be dramatically
improved by imposing suitable conditions for accepting incoming traffic; the
proposed system performs well under different traffic settings, and it
successfully adapts to changes in the operating environment.Comment: 11 pages, 9 Figures,
http://www.wipo.int/pctdb/en/wo.jsp?WO=201002636
E3MS: A traffic engineering prototype for autoprovisioning services in IP/DiffServ/MPLS networks
This paper presents the testbed definition, implementation and trials of a new strategy for traffic autoprovisioning for MPLS and IP/DiffServ. This is the proof of concept of a new scenario for traffic engineering, for selfconfiguring control and end-to-end quality of service management by means of a tool based on Web Services. The system is structured in 3 layers: A Graphical User Interface, a Network Elements layer (an interface to physical devices) and, in the middle, a Network Management System layer, where decisions about admission, load balancing, path selection, rerouting and bandwidth allocation per class are taken. The system includes Dynamic Resource Allocation (DRA) and Background Monitoring System (BMS) modules to globally manage network resources. The so-called Squatter and Legalization mechanisms are introduced as novelties added to traffic engineering. Those strategies permit the use of part of the available resources from other classes only while unused by the class owning them. The trials hav validated the management system, using Cisco routers.Postprint (published version
Revenue maximization problems in commercial data centers
PhD ThesisAs IT systems are becoming more important everyday, one of the main concerns is that users may
face major problems and eventually incur major costs if computing systems do not meet the expected
performance requirements: customers expect reliability and performance guarantees, while
underperforming systems loose revenues. Even with the adoption of data centers as the hub of
IT organizations and provider of business efficiencies the problems are not over because it is extremely
difficult for service providers to meet the promised performance guarantees in the face of
unpredictable demand. One possible approach is the adoption of Service Level Agreements (SLAs),
contracts that specify a level of performance that must be met and compensations in case of failure.
In this thesis I will address some of the performance problems arising when IT companies sell
the service of running âjobsâ subject to Quality of Service (QoS) constraints. In particular, the aim
is to improve the efficiency of service provisioning systems by allowing them to adapt to changing
demand conditions.
First, I will define the problem in terms of an utility function to maximize. Two different models
are analyzed, one for single jobs and the other useful to deal with session-based traffic. Then,
I will introduce an autonomic model for service provision. The architecture consists of a set of
hosted applications that share a certain number of servers. The system collects demand and performance
statistics and estimates traffic parameters. These estimates are used by management policies
which implement dynamic resource allocation and admission algorithms. Results from a number of
experiments show that the performance of these heuristics is close to optimal.QoSP (Quality of Service Provisioning)British Teleco
An Architecture for QoS-Enabled Mobile Video Surveillance Applications in a 4G EPC and M2M Environment
© 2016 IEEE. Mobile video surveillance applications are used widely nowadays. They offer real-time video monitoring for homes, offices, warehouses, airports, and so on with live and pre-recorded on-demand video streaming. Quality of service (QoS) remains a key challenge faced by most of these applications. In this article, we propose an architecture for mobile video surveillance applications with a guaranteed and differentiated QoS support. The architecture relies on the 3GPP 4G evolved packet core (EPC). The main components are the QoS enabler, media server, and machine-to-machine gateway and surveillance application. To demonstrate its feasibility, a proof of concept prototype has been implemented and deployed. We also took measurements to evaluate the performance. Several lessons were learned. For instance, multimedia frameworks must allow for buffering controls in media streaming to reduce live streaming delay. In addition, we have learned that publicly available materials related to the EPC prototyping platform we have used (i.e., OpenEPC) are scarce. This has made our prototyping task rather difficult
A Real-Time Service-Oriented Architecture for Industrial Automation
Industrial automation platforms are experiencing a paradigm shift. New technologies are making their way in the area, including embedded real-time systems, standard local area networks like Ethernet, Wi-Fi and ZigBee, IP-based communication protocols, standard service oriented architectures (SOAs) and Web services. An automation system will be composed of flexible autonomous components with plug & play functionality, self configuration and diagnostics, and autonomic local control that communicate through standard networking technologies. However, the introduction of these new technologies raises important problems that need to be properly solved, one of these being the need to support real-time and quality-of-service (QoS) for real-time applications. This paper describes a SOA enhanced with real-time capabilities for industrial automation. The proposed architecture allows for negotiation of the QoS requested by clients from Web services, and provides temporal encapsulation of individual activities. This way, it is possible to perform an a priori analysis of the temporal behavior of each service, and to avoid unwanted interference among them. After describing the architecture, experimental results gathered on a real implementation of the framework (which leverages a soft real-time scheduler for the Linux kernel) are presented, showing the effectiveness of the proposed solution. The experiments were performed on simple case studies designed in the context of industrial automation applications
Grid Analysis of Radiological Data
IGI-Global Medical Information Science Discoveries Research Award 2009International audienceGrid technologies and infrastructures can contribute to harnessing the full power of computer-aided image analysis into clinical research and practice. Given the volume of data, the sensitivity of medical information, and the joint complexity of medical datasets and computations expected in clinical practice, the challenge is to fill the gap between the grid middleware and the requirements of clinical applications. This chapter reports on the goals, achievements and lessons learned from the AGIR (Grid Analysis of Radiological Data) project. AGIR addresses this challenge through a combined approach. On one hand, leveraging the grid middleware through core grid medical services (data management, responsiveness, compression, and workflows) targets the requirements of medical data processing applications. On the other hand, grid-enabling a panel of applications ranging from algorithmic research to clinical use cases both exploits and drives the development of the services
G-QoSM: Grid Service Discovery Using QoS Properties
We extend the service abstraction in the Open Grid Services Architecture citeogsa for Quality of Service (QoS) properties. The realization of QoS often requires mechanisms such as advance or on-demand reservation of resources, varying in type and implementation, and independently controlled and monitored. Foster et al. propose the GARA citeFostKessl99 architecture. The GARA library provides a restricted representation scheme for encoding resource properties and the associated monitoring of Service Level Agreements (SLAs). Our focus is on the application layer, whereby a given service may indicate the QoS properties it can offer, or where a service may search for other services based on particular QoS properties
Proof-of-Concept Application - Annual Report Year 1
In this document the Cat-COVITE Application for use in the CATNETS Project is introduced and motivated. Furthermore an introduction to the catallactic middleware and Web Services Agreement (WS-Agreement) concepts is given as a basis for the future work. Requirements for the application of Cat-COVITE with in catallactic systems are analysed. Finally the integration of the Cat-COVITE application and the catallactic middleware is described. --Grid Computing
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