My research is mainly focused on the following topics:

Data dissemination through the publish/subscribe paradigm


The publish/subscribe communication paradigm is an appealing alternative to the traditional request/reply sibling for all those applications where many-to-many data diffusion is heavily used. My research in this area focused on the design of new event routing mechanisms for distributed publish/subscribe systems; these mechanisms, applied on both managed and peer-to-peer systems, leverage clustering techniques to improve performance. Clustering, in fact, is used to put close in the overlay network on which event routing is realized, users sharing similar interest, reducing in this way the average number of messages generated to diffuse data. Currently I'm also investigating if and how the OMG's DDS (Data Distribution Service) specification can be implemented in large-scale settings.

Peer-to-peer overlay networks


Distributed applications faced in the last decade an enormous growth tanks to the introduction of the peer-to-peer interaction model. These applications are based on an infrastructure (overlay network) whose main purpose is to maintain a logical network connecting all the users. In this research area my interests were mainly focused on the study of gossip-based algorithm for the maintenance of random-like overlay network topologies, and, more specifically, on the impact of churn (the continuous addition/removal of users to the system) on these algorithms. In the same context, I also worked on the definition of a general framework for the implementation of distributed quorum systems for DHT-based overlay networks.

Mobile ad-hoc networks


Mobile ad-hoc networks (MANETs) are constituted by mobile nodes communicating directly though wireless network adapters without the need of any fixed infrastructures. Such systems pose challenging problems that have a huge impact at various level of the network stack: from low level communication protocols, up to applications. In this research field I worked on the design of a novel message routing protocol that tries to avoid the shortcomings of classic approaches, originally thought for static networks and then adapted to the mobile world. The proposed protocols leverage the peculiar characteristics of the wireless medium to probabilistically track node movements, and then uses this information to route messages. This technique has been first employed to implement an unicast communication primitive, and then to realize a simple, but effective, event routing mechanism for publish/subscribe.