Design and Implementation of High-Availability-Driven Service Delivery Framework for Mobile Devices

• Main Authors: Chen, Ping-Chang, 陳炳璋
• Other Authors: Ma, Shang-Pin
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/30007462032545026221

碩士 === 國立臺灣海洋大學 === 資訊工程學系 === 102 === How to provide continued and smooth access to web services from smartphones under unstable network or during network disconnections is an important issue to be solved. In the past decade, many methods for service caching have been proposed, however, two significant concerns are usually overlooked in these methods: (1) a variety of contexts: users may use smartphones in a variety of network conditions, such as high-speed network, unstable network, and no network access; and (2) service error handling and recovery: currently, the service caching mechanism can tackle the problem of unavailability temporarily, but cannot handle the long-time service errors or malfunctions. In this paper, we propose a context-aware and risk-driven (CARD) RESTful service delivery approach to address the above issues. The CARD approach is encapsulated as client-side library to be utilized by mobile applications to invoke backend RESTful services in a highly-available manner. There are two main features of CARD approach: First, CARD can perform different actions for different network conditions, such as prefetching service responses and using cached service in high speed wireless network, only using cached service in unstable wireless network, and allowing the user to request cached service response from other users when no wireless network can be accessed. Second, based on the proposed risk-driven analysis method, CARD can supply reasonable service recovery plan when the original service is malfunctional. The implementation and experiment demonstrate that the proposed CARD approach can effectively improve service availability and shorten service response time in various network conditions.