Design And Implementation Of Address Allocation Based On RPL Routing Protocol In Wireless Sensor Networks

In Wireless Sensor Networks (WSNs), sensor nodes typically have limited computing and storage capabilities. Traditional routing protocols usually need to store large amounts of routing state information, and will generate a lot of control overhead in process of routing, so they do not fit for the resource-constrained WSNs. IETF Roll Working Group presents a special routing protocol for the low-power and lossy networks named RPL (IPv6Routing Protocol for Low-Power and Lossy Networks). It aims to solve the resource-constrained problem and reduce storage requirements and routing signaling overhead. However, in the large-scale networking environment, the address configuration in RPL may cause some new problems as follows. The uneven distribution of sensor nodes leads to a waste of address resources, and frequent changes of network topology result in too much routing overhead and network maintenance overhead.This paper proposes a hierarchical addressing scheme for the large-scale WSNs, which the hierarchical form can reflect the network topology. In our approach, we can immediately locate the information of a node’s subnet and parent node through its address, which saves the network maintenance overhead. Especially when the nodes communicate with nodes in different subnets, communication path can be informed in advance by the address information, which greatly reducing the time of querying and matching routing table, and saving the routing overhead. Additionally, this paper also presents the concept of addresses lease and a dynamic mechanism coping with network merging to reduce network maintenance overhead caused by the network frequent unrest of the network. The uneven distribution of nodes that leads to the waste of address resource can also be solved by the proposed scheme. Simulation on the cooja simulator and implementation on60real sensor nodes verify the feasibility of the scheme.