多租戶服務為涉及軟體即服務模式與平台即服務模式的一種服務概念。租戶可以透過與服務供應商協商的過程客製化個人需求，並記錄作為未來取得與審視服務內容的依據。由於軟體服務的日益普及，提供租戶多樣化的服務選擇，要如何從候選多租戶服務中選擇合適的服務，將形成一個重要的研究議題。因此，本研究將探索多租戶服務層級協議之效用模式，並基於此效用模式來對多租戶服務進行多準則決策分析，用以產生最佳化候選服務之選擇排名。首先，我們先正規化多租戶服務之服務層級協議，並討論符合其設定項目之效用模式；接著，多準則決策分析將用於發掘候選多租戶服務之選擇排名，這樣的選擇排名將可推薦並協助租戶獲取符合個人化需求的多租戶服務。本研究的貢獻在於透過簡單的數理模式演繹，介紹最佳化多租戶服務選擇概念，使用方法亦容易實作於現行軟體服務推薦系統，協助使用者找尋符合需求的適當服務。

Multi-tenancy service is one service concept involved with software as a service (SaaS) and platformas a service (PaaS). A tenant can customize personal requirements in a multi-tenancy service levelagreement (SLA) by negotiating with the service provider. Due to the popularity of software services, how toselect a reasonable service from various multi-tenancy services has become an important issue. Therefore,this research explores the utility function of the SLA and uses an approach for the optimal selection of amulti-tenancy service based on a SLA utility function. The approach formalizes the SLA and discusses a utilitymodel for the SLA’s configuration items. Then, the multi-criteria decision analysis is used to discover thereasonable selection order of multi-tenancy services. The selection order helps a tenant acquire a reasonablemulti-tenancy service which meets his personal requirements. This work demonstrates a method which is easyto implement in a software service recommendation system for selecting a reasonable multi-tenancy service.