Concentration Gradient based Routing for Molecular Nanonetworks

Due to the limited capabilities of nodes in biological nanonetworks, several nodes need to cooperate to perform complicated tasks. Therefore, a simple and efficient routing scheme is crucial for these networks. In this paper, a novel routing mechanism that utilizes a concentration gradient to guide routing towards the sink is proposed. In contrast to previous schemes that rely on a predetermined network topology or frequent information exchange for finding a routing path, thus incurring additional implementation cost, we utilize capabilities of bacteria, such as directional sensing and molecule prioritization, to design a simple to implement routing scheme which can facilitate information transfer towards a sink node. A simulative study is conducted and the properties of a multi-molecular field are investigated when changing parameters such as the rebroadcast period, the threshold initiating retransmission at the relay nodes and the transmission intensity. In addition, the effectiveness of the method is investigated in terms of the probability of successful message delivery and the associated propagation delay. Results demonstrate that with the appropriate selection of design variables, successful delivery probabilities close to 1 can be achieved, while at the same time maintaining small propagation delays.