Validation of Wireless and Mobile Network Models and Simulation

TLDR: Wireless and mobile networks present substantial challenges in the validation of large-scale network models and simulation, even beyond the already difficult problem of validation in more conventional wired and stationary networks.

Abstract: Wireless and mobile networks present substantial challenges in the validation of large-scale network models and simulation, even beyond the already difficult problem of validation in more conventional wired and stationary networks. These additional challenges are due to the complications and subtleties of physical movement and wireless propagation, making the system highly variable and substantially increasing the complex interactions between the parts of the system and the surrounding environment. These same factors also make wireless and mobile experiments in the real world not easily or accurately repeatable, reducing the use of such experiments for validation. In particular, the position and movement of nodes in the network can have a significant effect on the behavior and performance of the system being modeled. The position and possible movement of other objects in the environment around the nodes themselves, such as buildings, hills, and trees, or vehicles, people, and rain, can also significantly effect the system being modeled. Furthermore, to accurately control an entire experiment in the real world, all of these positions and movements would need to be controlled to within a fraction of a wavelength of the radios involved, due to differences in the radio multipath environment even such small position differences can cause. Having complete control over all of these factors is simply not fully achievable in any real system, and so models and real experiments, to some degree, can only be approximations.