Erbin Lim

Towards a community-based, social network-driven framework for Web services management

This paper discusses a framework to manage Web services using the concept of community and the metaphor of social networking. On the one hand, a community gathers Web services that offer similar functionalities together. These Web services are referred to as either master or slave. On the other hand, social networking captures all interactions that occur between Web services located in the same or separate communities. Five interactions are identified and referred to as supervision, substitution, competition, collaboration, and recommendation. The mining exercise over the social networks that capture these interactions results in assigning social qualities to Web services, similar to those found in peoples daily life such as selfishness, fairness, and trustworthiness. Experiments showing the mining exercise are also reported in this paper.

Social Engineering of Communities of Web Services

This paper discusses the engineering of communities of Web services with emphasis on the social interactions that arise between these Web services and hence, can put some restrictions on their behaviors. Like service parks, communities gather Web services that offer similar functionalities to users. The social interactions between Web services take place within and across communities and are captured using structures known as social networks. Five types of networks are established during this engineering, which are supervision, competition, substitution, collaboration, and recommendation. Above these networks mining operations are performed, which results in assigning social attributes to Web services such as selfishness, fairness, and unpredictability. Details on the experiments are, also, reported in this paper.

Towards Defining and Assessing the Non-functional Properties of Communities of Web Services

This paper discusses some of the research done in the area of communities of Web services. A community allows Web services offering similar functionalities to be grouped together. One challenge that arises as a result of this grouping concerns the assessment of the level of service of the community. We refer to this level of service as Quality of Community (QoC). The QoC is important as it permits differentiating the communities from each other as well as promoting and maintaining a certain service level in preparation for receiving user requests for processing. The QoC of a community is assessed based on the QoSs of the individual Web services that reside in this community. Different attributes specific to the community such as variance, selection rate, and substitution rate define the QoC. Experiments illustrating the use of the QoC are, also, reported in this paper.

Using 3-Way Satisfaction for Web Service Selection: Preliminary Investigation

This paper examines the problem of Web service selection in a community. Web services reside in communities due to the similiar functionalities they offer. The selection in communities is important because each Web service provides a different level of service. Selection methods thus far only consider the satisfaction of users and neglect the satisfaction of Web services and the community to which they belong. In this paper we propose a method of selecting a Web service based on the satisfaction of all three parties - user, Web service and community. The proposed solution consists of first formalizing the selection process and then using linear programming techniques to define a score function, which can be maximized to find the best selection based on the three satisfaction factors.

Communication of Technical QoS among Cloud Brokers

Service brokers are commonly used in the cloud computing paradigm to represent service requesters to select a service provider. They act as an intermediary between the two parties. One model of the cloud computing paradigm involves 3 layers, the user, the SaaS provider and the Cloud provider. The selection of service requesters is challenging due to the different levels of Quality of Service that each service provider can provide. In this paper we propose a unique mechanism that allows communication between service brokers in different layers in order to further improve this selection. In addition, we introduce a metric, efficiency, which service brokers can use to deterministically compare service providers with each other.

Sustaining high-availability and quality of web services

In this work, we study how to sustain the high availability and quality of Web services by using communities of Web services. Availability is the probability that a Web service is in functioning condition at a specific time. Communities of Web services gather Web services that provide the same functionality, but not necessary with the same quality. Within this framework, an available Web service can be selected or even substituted by another one when it fails. In this research, we aim at investigating how to manage the community to sustain not only the high availability but also to guarantee the quality of service expected by the user.

Using Fixed-Price Auctions for Selection in Communities of Web Services

This paper introduces an approach that allows Web services to handle user requests where the price that the users are willing to pay is fixed. In such cases, a user search for the highest quality of service based on the submitted fixed price. Instead of searching for individual Web services, the user finds it more convenient to send requests to middlemen (or brokers) who act on behalf of a group of Web services. These middlemen then select a Web service within the group to handle the request. In this paper we demonstrate how fixed price requests can be included into the operation of a community of Web services. Our approach introduces auction theory into the selection process. Experiments using real world values are conducted to demonstrate the effectiveness of the approach.

UsiWSC: Framework for Supporting an Interactive Web Service Composition

In this paper, we propose the UsiWSC framework for designing, deploying and executing Web service compositions with user interactions. The UsiWSC design relies on an extension of the BPEL standard: UI-BPEL. The extension supports the derivation of user interfaces as well as executable compositions for different user contexts. The UsiWSC execution requires the coordination of the control and data flows between web services and user interfaces.