- Multicast potentially optimises bandwidth consumption and node resources, when several users simultaneously participate in a communication session. Nevertheless, contrary to the expectations, IP multicast has not experienced widespread deployment, with the exception of IPTV. On the other hand, emerging Wireless Sensor Network (WSN) applications could greatly benefit from multicast and constitute another field where multicast can be an effective and efficient technique. The questions are: do multicast advantages hold in WSN scenarios? Can we use IP Multicast functionality in WSNs? This paper discusses and evaluates the use of multicast in WSNs. Specifically, we evaluate the use of Source-Specific Multicast, as it is one of the most promising paradigms for IP networking, considering both IPv4 and IPv6 in WSNs. A sensor platform with IP and multicast support that is being developed in our lab is presented. Concurrently, simulation studies were performed in order to assess the usefulness...