Differentiated service

About: Differentiated service is a research topic. Over the lifetime, 5539 publications have been published within this topic receiving 105225 citations.

On the fly service composition for local interaction environments

Abstract: Dynamically creating new, composite services "on the fly" using existing ones in a local interaction environment (e.g. a home, meeting room, airport lounge, etc.) presents challenging problems. In this paper, we describe a middleware model for such service composition targeted, initially, to a home area network (HAN) scenario. Being able to automatically synthesize new and useful services in a HAN (or other environment) without user intervention makes the use of the network simpler and more attractive for non-expert users (e.g. home owners). We propose a service composition model which involves third-party "service providers" (SPs) in the composition process thereby allowing the discovery of services without direction from the users as to what type of service is desired. We also discuss our experiences with our initial prototype system where ontology based matching is done by the service providers and the resulting composite service is deployed as a workflow using available in-home protocols (e.g. UPnP, Jini, etc.).

Providing differentiated service from an Internet server

Abstract: Differentiated service has been proposed as a potential solution for bandwidth allocation and is expected to be supported in the next-generation Internet. However, a service-differentiating Internet with best-effort servers may not meet the overall goals of the differentiated service. In this paper, approaches and performance issues on providing differentiated services from an Internet server are studied. Experimental study and analyses prove that under near-saturation of server utilization, differentiating service provides significantly better performance to high priority tasks compared to a traditional service mode. Quantitative performance estimation of different priority levels of tasks is presented. It is also observed that an enhanced shortest queue first task assignment scheme helps in decreasing the average response time of the server system.

An Adaptive Access Control Model for Web Services

Abstract: This paper presents an innovative access control model, referred to as Web service Access Control Version 1 (Ws-AC1), specifically tailored to Web services. The most distinguishing features of this model are the flexible granularity in protection objects and negotiation capabilities. Under Ws-AC1, an authorization can be associated with a single service and can specify for which parameter values the service can be authorized for use, thus providing a fine access control granularity. Ws-AC1 also supports coarse granularities in protection objects in that it provides the notion of service class under which several services can be grouped. Authorizations can then be associated with a service class and automatically propagated to each element in the class. The negotiation capabilities of Ws-AC1 are related to the negotiation of identity attributes and the service parameters. Identity attributes refer to information that a party requesting a service may need to submit in order to obtain the service. The access control policy model of Ws-AC1 supports the specification of policies in which conditions are stated, specifying the identity attributes to be provided and constraints on their values. In addition, conditions may also be specified against context parameters, such as time. To enhance privacy and security, the actual submission of these identity attributes is executed through a negotiation process. Parameters may also be negotiated when a subject requires use of a service with certain parameters values that, however, are not authorized under the policies in place. In this paper, we provide the formal definitions underlying our model and the relevant algorithms, such as the access control algorithm. We also present an encoding of our model in the Web Services Description Language (WSDL) standard for which we develop an extension, required to support Ws-AC1.

Service-Oriented Product Lines: Towrads a Development Process and Feature Management Model for Web Services.

Abstract: Service-Oriented Architecture fosters the loose coupling of services aimed at maximizing flexibility, adaptability and configurability. Services of different providers can easily be integrated into a common framework with standardized technology like Web Services. A Software Product Line depicts a systematic software reuse approach by handling various types of flexible software artifacts that form a common platform and are the basis for deriving concrete products. This paper contributes towards the combination of both concepts by proposing a differentiated development process for Software Product Lines implementing a ServiceOriented Architecture. An extensive example shows how parts of this process can be solved technically with already developed methods for feature modeling and management using Web Services.

MODM-based Evaluation Model of Service Quality in the Internet of Things

Abstract: The Internet of Things (IOT) which is considered to be the next step of the revolution of internet lets us transform everyday objects into smart objects that can understand and react to their environment. For achieving the intelligent service provision in IOT environment depending on the context resource, a mechanism for Quality of Service (QoS) management which can analyze the contexts and employ methods to evaluate QoS is greatly needed. In this paper, a multi-objective decision making (MODM) based evaluation model of service quality is proposed. Both the resource state and the user preferences are taken into consideration in order to improve the reasonableness of the QoS evaluation model. The calculated result of the proposed model can act as a metric for service evaluation and selection. © 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of [name organizer]