This simulator supports multiple mobile sink.
if you are looking for the one-sink ring routing plz go to "https://github.com/howbani/RingRouting".
Mobile sinks are proposed for load-balancing and achieving uniform energy-consumption in wireless sensor networks. However, advertising the location of the mobile sink to the network introduces an overhead in terms of energy consumption and packet delays. In this paper, we propose a new routing protocol, Ring Routing, which aims to minimize this overhead while preserving the advantages of mobile sinks. Simulation results show that the performance of Ring Routing is not very far from the lower bound in terms of delay and energy consumption.