以代理人實作SLA服務監測系統

Using Agent to Implement SLA-based Service Monitoring Systems

陳建麒(Chienchi Chen)

指導教授 ： 周立德

國立中央大學/資訊電機學院/資訊工程學系/碩士(2006年)

摘要

Web服務 (Web Service)技術近年來受到各界的歡迎，採用開放式標準(如HTTP和XML 等)，讓Web Service具有良好互通性並且整合異質平台溝通的特性，克服目前分散式系統各自使用不同機制造成整合困難的情形，然而服務品質 (Quality of Service，簡稱QoS) 整合在Web Service 而言更形重要。對於服務需求者而言，由服務品質可看出服務的優劣以作為服務需求者的參考。
本論文將提出利用代理者的服務監測機制，主要針對服務需求者與服務提供者雙方所簽定的服務等級協議 (Service Level Agreement，簡稱 SLA) 作服務監控的機制並且管理SLA合約，當有違反合約的服務品質時，即可作適當的處理機制。本論文的貢獻為服務需求者可利用代理者得知目前監控服務的情況，在量測的效能方面提出的方法比傳統的方法快，針對回應時間的量測所量測平均回應時間比傳統量測平均回應時間約少於4.42%，另一方面，提出的服務管理架構提供服務提供者註冊具有SLA的服務，在實作SLA語言方面，採用XML Schema 去定義SLA 合約，以表達對各式各樣的SLA 需求。

關鍵字

服務等級協議 ； 服務品質 ； Web服務

並列摘要

With the development of Web Service technologies has become more and more popular in recent years. The open standard protocol, which is such as HTTP, XML and so on, has the properties of easy communication and interoperable. Therefore, the Web Service is based on the open standard protocol to solve the integrated problems about distributed system with the different platform. Besides, for the aspect of service requestor, they treat the criterion of service which can be decided by Quality of Service (QoS) as the reference, so it is the key issue to integrate QoS with Web Service.
This thesis proposed a mechanism using agent monitoring the service. The mechanism aims to manage the Service Level Agreement (SLA) and monitor the SLA which is a negotiation between service requestor and service provider. While any action infringes SLA, the mechanism will handle it with some appropriate functionality. On the one hand of our contributions is to provide a watched result monitored by agent to the service requestor. For the performance of measurement, the proposed approach is less the average Response Time than the traditional approach about 4.42%. Therefore, the proposed approach is more efficiency than the traditional approach. On the other hand, the proposed service management architecture also allows the service provider to register the service of SLA. Moreover, this thesis used the XML Schema to define SLA Language in order to achieve the required SLA for different providers.

並列關鍵字

Service Level Agreement ； Quality of Service ； Web Services

參考文獻

[17] Service Level Agreement, http://www.sics.se/~rabih/pdfs/sla.pdf.

[3] W3C, “Simple Object Access Protocol (SOAP) 1.2,” W3C Note, http://www.w3.org/TR/soap/, June 2003.

[5] M. Tian, A. Gramm, H. Ritter and J. Schiller, “A Concept for QoS Integration in Web Services,” Proceedings of the Fourth International Conference on Web Information Systems Engineering Workshops, Rome, Italy, 2003.

[7] H. Ludwig, “Web Services QoS: External SLAs and Internal Policies Or: How do we deliver what we promise,” Proceedings of the Fourth International Conference on Web Information Systems Engineering Workshops, Rome, Italy, 2003.

[9] A. Schmietendorf, R. Dumke and D. Reitz, “SLA Management –Challenges in the Context of Web Service Based Infrastructure,” Proceedings of the IEEE International Conference on Web Services, San Diego, California, USA, July 2004.