Context-aware Authorization in Highly Dynamic Environments

Highly dynamic computing environments, like ubiquitous and pervasive computing environments, require frequent adaptation of applications. Context is a key to adapt suiting user needs. On the other hand, standard access control trusts users once they have authenticated, despite the fact that they may reach unauthorized contexts. We analyse how taking into account dynamic information like context in the authorization subsystem can improve security, and how this new access control applies to interaction patterns, like messaging or eventing. We experiment and validate our approach using context as an authorization factor for eventing in Web service for device (like UPnP or DPWS), in smart home security

Context-sensitive authorization for asynchronous communications

Main requirement of recent computing environments, like mobile and then ubiquitous computing, is to adapt applications to context. On the other hand, access control generally trust users once they have authenticated, despite the fact that they may reach unauthorized situations. We analyse how dynamic information can be used to improve security in the authorization process, especially in the case of asynchronous communications, like messaging or eventing. We experiment and validate our approach using context as an authorization factor for eventing in Web service for device (like UPnP or DPWS)

SIMPLEstone: Benchmarking Presence Server Performance

Presence is an important enabler for communication in Internet telephony systems. Presence-based services depend on accurate and timely delivery of presence information. Hence, presence systems need to be appropriately dimensioned to meet the growing number of users, varying number of devices as presence sources, the rate at which they update presence information to the network and the rate at which network distributes the user's presence information to the watchers. SIMPLEstone is a set of metrics for benchmarking the performance of presence systems based on SIMPLE. SIMPLEstone benchmarks a presence server by generating requests based on a work load specification. It measures server capacity in terms of request handling capacity as an aggregate of all types of requests as well as individual request types. The benchmark treats different configuration modes in which presence server interoperates with the Session Initiation protocol (SIP) server as one block