Boundary node detection in wireless networks with uneven node distribution on open surfaces

Boundary node detection is essential in various application scenarios of wireless networks. However, most previous solutions are only suitable for planar networks with densely and evenly distributed nodes. They cannot satisfy scenarios where nodes are unevenly deployed on open surfaces because the nodes may have different heights, densities, and inter-distances. In this work, we propose a scheme named Surrounding Triangle Validation to detect boundary nodes in wireless networks with uneven node distribution on open surfaces. This solution randomly generates triangles from the 1-hop neighbors of a testing node and validates these triangles. The triangle generation step accepts the triangles with their two endpoints connected by one or more relay nodes in the areas with uneven node density. Then, the generated triangles surrounding the testing node are picked out by point in triangle tests. In the last step, the selected triangles are compared according to the characteristics of a special kind of boundary node to ensure the results of our method. We test our solution in networks with different node densities on several open surfaces. Simulation results show that our method works effectively. It detects boundary nodes more correctly than previous solutions.