ROUDIER Y.

It is a well known fact that user-chosen passwords are somewhat predictable: by using tools such as dictionaries or probabilistic models, attackers and password recovery tools can drastically reduce the number of attempts needed to guess a password. Quite surprisingly, however, existing literature does not provide a satisfying answer to the...

User connectivity patterns in network applications are known to be heterogeneous and to follow periodic (daily and weekly) patterns. In many cases, the regularity and the correlation of those patterns is problematic: For network applications, many connected users create peaks of demand; in contrast, in peer-to-peer scenarios, having few users...

Expressing security policies to govern distributed systems is a complex and error-prone task. Policies are hard to understand, often expressed with unfriendly syntax, making it difficult for security administrators and for business analysts to create intelligible specifications. We introduce the Hierarchical Policy Language for Distributed...

Expressing security policies to govern distributed systems is a complex and error-prone task. Policies are hard to understand, often expressed with unfriendly syntax, making it difficult to security administrators and to business analysts to create intelligible specifications. We introduce the Hierarchical Policy Language for Distributed...

OAuth 2.0 is a recent IETF standard devoted to providing authorization to clients requiring access to specific resources over HTTP. It has been pointed out that this framework is potentially subject to security issues, as well as difficulties concerning the interoperability between protocol participants and application evolution. As we show in...