Systems and methods for creating scalable presence subscriptions in federated presence environments

Abstract

Systems and associated methods for providing scalable presence subscriptions in federated presence environments are described. Embodiments provide for intelligent addition of subscriptions to a presence system. Embodiments identify if a virtualized presentity (corresponding to a new query) can be composed from existing virtualized presentities, and if so, corresponding query processing cells (QPCs) (servicing existing queries) are reused to retrieve the presence information (partially or fully) for the new incoming query. Embodiments organize the existing QPCs into a hierarchy such that a QPC/virtual presentity at a higher layer fetches presence information of all or some presentities from QPCs/virtual presentities at lower layer(s) to service the new query.