Causally Ordered Delivery Protocol for Overlapping Multicast Groups in Broker-Based Sensor Networks
In sensor networks, there are a lot of overlapping multicast groups because of many subscribers, associated with their potentially varying specific interests, querying every event to sensors/publishers. Also gossip-based communication protocols are promising as one of potential solutions providing scalability in P (Publish)/S (Subscribe) paradigm in sensor networks. Moreover, despite the importance of both guaranteeing message delivery order and supporting overlapping multicast groups in sensor or P2P networks, there exist little research works on development of gossip-based protocols to satisfy all these requirements. In this paper, the authors present a causally ordered delivery guaranteeing protocol for overlapping multicast groups, based on sensor-brokers as delegates. In the protocol based on sensor-broker, sensor-broker might lead to make overlapping multicast groups organized by subscriber's interests.