There has been growing attention to the realm of Self-Sovereign Identities (SSI) in the past few years, with significant effort being put into the development of standards and specifications, such as Decentralized Identifiers (DIDs), to be in conformity with essential identity prerequisites such as decentralization, privacy and interoperability. However, the portability of DIDs is still an under-researched topic, even though it is a requirement of great importance in order to guarantee user autonomy amidst the numerous implementations being developed by the industry. In this paper, we explore the concept of portability of DIDs, highlighting how the current standards and protocols don't fully address this major point. We also define key requirements for addressing this feature, and discuss some major concerns on security and privacy that may emerge with the development of DID portability schemes.

Regulations and consumer backlash force many organizations to re-evaluate the way they manage private data. As a first step, they publish privacy promises as text or P3P. These promises are not backed up by privacy technology that enforces the promises throughout the enterprise. Privacy tools cover fractions of the problem while leaving the main challenge unanswered.This article describes a new approach towards enterprise-wide enforcement of the privacy promises. Its core is a new framework for managing collected personal data in a sensitive, trustworthy way. The framework enables enterprises to publish clear privacy promises, to collect and manage user preferences and consent, and to enforce the privacy promises throughout the enterprise.One of the foundations of this framework is the "sticky policy paradigm" that defines a customer centric model for managing policies, preferences, and consent.

The perceived lack of security in the wireless environment has delayed many initiatives in providing access to E-commerce applications from wireless devices. Many organizations are skeptical that the same kind of security protections that they are used to in the current Internet (wired) E-commerce environment are also available for wireless transactions. We show that these perceptions are misplaced. We describe the security properties and mechanisms available for Internet (wired), WAP based and iMode E-commerce. We find that both WAP and iMode provide excellent security features and are geared to provide other security provisions over and above those commonly available in a wired environment.

As the use of information technology is increasing rapidly in organizations around the world, an important task is to design global networks with high security, eÆciency and functionality.While centralized systems have the advantages of simpli ed management, they face the problems of bottleneck and single point of failure.In this paper, we propose a new authorization scheme that operates over existing centralized authentication mechanisms.The goal is to enhance the performance and scalability in a centrally administered security architecture.A new technique of using one-shot authorization toke n s i s i n troduced.It facilitates a mechanism for updating or revocation of the access rights of users in online or o-line authorization models.A smart card is used as an authorization device in addition to its traditional function of user authentication.This scheme provides the mobility for users and the exibility in coping with dierent access control policies in a cross domain multi-application environment.