Browsing by Author "Younas, Muhammad"

Now showing 1 - 5 of 5

A fuzzy outranking approach in risk analysis of web service security
(2007-03-01)
Wang, Ping
;
Chao, Kuo-Ming
;
Lo, Chi-Chun
;
Huang, Chun-Lung
;
Younas, Muhammad
Risk analysis is considered as an important process to identify the known and potential vulnerabilities and threats in the web services security. It is quite difficult for users to collect adequate events to estimate the full vulnerabilities and probability of threats in the Web, due to the rapid change of the malicious attacks and the new computers vulnerabilities. In this paper, a fuzzy risk assessment model is developed in order to evaluate the risk of web services in a situation where complete information is not available. The proposed model extends Pseudo-Order Preference Model (POPM) to estimate the imprecise risk based on richness of information and to determine their ranking using a weighted additive rule. A case Study of a number of web services is presented in order to test the proposed approach.
An efficient transaction commit protocol for composite web services
(2006)
Younas, Muhammad
;
Chao, Kuo-Ming
;
Lo, Chi-Chun
;
Li, Yinsheng
;
資訊管理與財務金融系註：原資管所+財金所
Transaction commit protocols have widely been used to ensure the correctness and reliability of distributed applications. This paper investigates into the performance of such protocols within the context of composite web services. It presents a new commit protocol which aims to improve the performance of composite web services transactions. The proposed protocol is tested through various analytical experiments. These experiments reveal that the proposed protocol significantly improves the performance in committing a composite web service transaction. The experiments also exhibit the processing overhead of the proposed protocol in the case of unsuccessful execution of a web service transaction.
Consumer-centric QoS-aware selection of web services
(2008-03-01)
Lin, Wei-Li
;
Lo, Chi-Chun
;
Chao, Kuo-Ming
;
Younas, Muhammad
;
資訊管理與財務金融系註：原資管所+財金所
There exist many web services which exhibit similar functional characteristics. It is imperative to provide service consumers with facilities for selecting required web services according to their non-functional characteristics or quality of service (QoS). However, the selection process is greatly complicated by the distinct views of service providers and consumers on the services QoS. For instance, they may have distinct views of the service reliability-wherein a consumer considers that a service is reliable if its success rate is higher than 99%, while a provider may consider its service as reliable if its success rate is higher than 90%. The aim of this paper is to resolve such conflicts and to ensure consensus on the QoS characteristics in the selection of web services. It proposes a QoS Consensus Moderation Approach (QCMA) in order to perform QoS consensus and to alleviate the differences on QoS characteristics in the selection of web services. The proposed approach is implemented as a prototype tool and is tested on a case study of a hotel booking web service. Experimental results show that the proposed approach greatly improves the service selection process in a dynamic and uncertain environment of web services. (c) 2007 Elsevier Inc. All rights reserved.
Fuzzy consensus on QoS in web services discovery
(2006)
Lin, Wei-Li
;
Lo, Chi-Chun
;
Chao, Kuo-Ming
;
Younas, Muhammad
;
資訊管理與財務金融系註：原資管所+財金所
Ensuring consensus on QoS attributes is imperative for the discovery of web services. Inconsistent views of service providers and consumers on QoS attributes could be problematic, even though they have consensus on characteristics. For instance, they may have distinct views of the QoS attribute of service reliability, wherein a consumer considers that a service is reliable if its success rate is 99.9% or 100016, while providers may consider its service as reliable if its success rate is higher than 90% Different expectations in service discovery could hinder prevailing of the web services. This paper proposes a QoS Consensus Moderation Approach (QCMA) in order to perform QoS consensus and to alleviate the differences on QoS requirements in the web services discovery. The proposed approach is implemented and evaluated through an example of hotel booking web service.
QoS-aware mobile service transactions in a wireless environment
(2007-06-10)
Younas, Muhammad
;
Chao, Kuo-Ming
;
Wang, Ping
;
Huang, Chun-Lung
;
資訊管理與財務金融系註：原資管所+財金所
Mobile computing greatly facilitates the provision of mobile services using portable and handheld devices which are connected through wireless networks. A pre-requisite for the provision of an effective service is to ensure quality of service (QoS) during the concurrent execution of requests and system or network failures. This paper presents a new transaction management approach for the provision of mobile services which is based on advanced transaction models and fuzzy selection criteria. It employs a novel QoS consensus moderation approach in order to select preferred mobile services from among various alternatives, thus providing multiple pathways to the completion of mobile service transactions. Unlike traditional transaction management schemes, the proposed approach takes into account QoS attributes in the commit process of mobile service transactions. The proposed approach is implemented as a prototype tool and evaluated through a number of experiments. Experimental results show that the proposed approach effectively selects mobile services and significantly increases the throughput (i.e. commit rate) of mobile service transactions. Copyright (C) 2007 John Wiley & Sons, Ltd.