On novelty in publish/ subscribe delivery

Abstract — In publish/subscribe systems, users express their interests in specific items of information and get notified when relevant data items are produced. Such systems allow users to stay informed without the need of going through huge amounts of data. However, as the volume of data being created increases, some form of ranking of matched events is needed to avoid overwhelming the users. In this work-in-progress paper, we explore novelty as a ranking criterion. An event is considered novel, if it matches a subscription that has rarely been matched in the past. I