Universal Fuzzy Access Control Policy Description Language Study

Mark Weiser proposed the concept of ubiquitous computing in the year of 1991.With the development of wireless network,distributed computing and mobile devices,ubiquitous computing has been the newest computing paradigm,and been noted in industry and research.However,there is still key theory and technology to solve to realize the characters of distributing,fuzzy and dynamy of ubiquitous computing,and the security of ubiquitous computing has become an important issue. Access Control grants subject to operate on objects based on predefined authorization polices to protect unanthorized information from being leaked.And,it is an essential technology to guarantee the security of the complex system.Now,there are several access control polices,including discretionary access control,mandatory access control,role-based access control,etc.However,due to the characters of fuzzy uncertainty and dynamic adaptability of ubiquitous computing access control,the existed access control polices cannot meet the needs,especially cannot express the fuzzy uncertainty of ubiquitous computing access control polices and the dynamic adaptability of ubiquitous computing access control strength,which are the most important differences between ubiquitous computing access control and the traditional access control.Now,the researches of ubiquitous computing mostly focus on its infrastructures and its applications,there is few research on the security.Thus,based on its characters of fuzzy uncertainty and dynamic adaptability,ubiquitous computing access control policy language is presented using interval-valued fuzzy set theory and interval-valued fuzzy reasoning method to realize the security of ubiquitous computing.There are different ideas and methods between ubiquitous computing access control and traditional access control.Firstly,reasonable and correct fuzzy concepts of elements and the interval-valued fuzzy sets in ubiquitous computing access control are presented.Then based on first order predicate,a new interval-valued fuzzy production rule is presented,which is the syntax of ubiquitous computing policy language.The rule can effectively describe the fuzzy uncertainty and dynamic adaptability of ubiquitous computing access control and keep the consistency between access control policy and security needs.Besides these,according to application needs,some first order fuzzy predicates are defined to describe the complex contexts.The main researches are outlined as follows:(1)Based on the characters of ubiquitous computing and interval-valued fuzzy set theory,the reasons of the fuzzy uncertainty and dynamic self-adaptability are analyzed,the fuzzy concepts of ubiquitous computing access control are proposed.And the fuzzy predicates and the fuzzy quantifiers of ubiquitous computing access control are defined,according to which the interval-valued fuzzy sets are established,which are fuzzy set theory basis of the research of ubiquitous computing access control.(2)The traditional access control policy language and its syntax structures are analyzed;these policy languages are compared in order to understand the content of a policy language.Then,the conditions the ubiquitous computing policy language must satisfy are pointed out.The context predicates,basic authorization predicates and the relationship predicates of subjects and objects are defined,as well as quantifiers and conjunction are defined to express complex access control polices.Furtherly,a new interval-valued fuzzy production rule is proposed as the syntax structure of ubiquitous computing access control policy language.(3)Taking the instance of Smart space—smart classroom as the application background,and in Microsoft.NET platform,using C# language to research related theory and method.This paper is supported by the Natural Science Foundation of Shaanxi Province of China(NO.: 2006F27),the Key Research Project of Ministry of Education of China(NO.:107106),the National Natural Science Foundation of China(NO.:60773224).