Network systems: general mobile computing with a focus on routing and content distribution in DTNs, MANETs, and social networks.
Network security: trust and reputation, general wireless security and privacy.
Network theory: applications of network coding and extended graph models for DTNs and cognitive radio networks.
Computer systems: GPU-based systems, multi-core applications in mobile phones, and energy-aware green computing.
Applied Machine Learning: wireless networks, crowdsourcing, and recommendation systems