Single sign-on (SSO) helps users to cope with many online services that require authentication. Systems such as OpenID and SAML-based Shibboleth offer federated identity management where an Identity Provider authenticates the user on behalf of the services. Much research concentrates on making authentication stronger, preventing phishing and making the systems more user friendly but less attent...

Web single sign-on (SSO) systems enable users to authenticate themselves to multiple online services with one authentication credential and mechanism offered by an identity provider. The topic is widely studied and many solutions exist. However, logging out of a service using SSO has received less attention. While previous studies note that users want single logout when using SSO, most of the e...

Received: 21 January 2011 Revised: 15 July 2011 2nd Revision: 06 February 2012 3rd Revision: 10 September 2012 4th Revision: 19 September 2013 Accepted: 30 September 2013 Abstract Electronic services such as virtual communities or electronic commerce demand user authentication. Several more or less successful federated identity management systems have emerged to support authentication across di...

let $g$ be a finite group with the identity $e$‎. ‎the subgroup intersection graph $gamma_{si}(g)$ of $g$ is the graph with vertex set $v(gamma_{si}(g)) = g-e$ and two distinct vertices $x$ and $y$ are adjacent in $gamma_{si}(g)$ if and only if $|leftlangle xrightrangle capleftlangle yrightrangle|>1$‎, ‎where $leftlangle xrightrangle $ is the cyclic subgroup of $g$ generated by $xin g$‎. ‎in th...

An e-learning discussion forum, an essential component of today’s e-learning systems, offers a platform for social learning activities. However, as learners participate in the discussion forum, privacy emerges as a major concern. Privacy concerns in social learning activities originate from one learner’s inability to convey a desired presentation of oneself to another learner. A user-controlled...

Research suggests that Black youth are less likely to use e-cigarettes than their white counterparts, yet little is known as to why. We examined perceptions of e-cigarettes among Black young adults (ages 18-25) to explore the meanings these youth ascribe to e-cigarettes and the role that identity plays in how these devices are viewed. Analysis of in-depth interviews with 36 Black smokers and no...

Definition. A group G consists of a set G together with a binary operation ∗ for which the following properties are satisfied: • (x ∗ y) ∗ z = x ∗ (y ∗ z) for all elements x, y, and z of G (the Associative Law); • there exists an element e of G (known as the identity element of G) such that e ∗ x = x = x ∗ e, for all elements x of G; • for each element x of G there exists an element x′ of G (kn...

A number of potential initiatives are being considered including the creation of a international electronic identity management infrastructure for trustworthy services in egovernment and e-commerce. A lot of work has been done in recent years in the field of electronic identity management, including through a series of research programs and pilot projects. While each of these projects contribut...