  Wireless Fidelity (WiFi) is the fastest growing wireless technology to date.
In addition to providing wire-free connectivity to the Internet WiFi technology
also enables mobile devices to connect directly to each other and form highly
dynamic wireless adhoc networks. Such distributed networks can be used to
perform cooperative communication tasks such ad data routing and information
dissemination in the absence of a fixed infrastructure. Furthermore, adhoc
grids composed of wirelessly networked portable devices are emerging as a new
paradigm in grid computing. In this paper we review computational and
algorithmic challenges of high-fidelity simulations of such WiFi-based wireless
communication and computing networks, including scalable topology maintenance,
mobility modelling, parallelisation and synchronisation. We explore
similarities and differences between the simulations of these networks and
simulations of interacting many-particle systems, such as molecular dynamics
(MD) simulations. We show how the cell linked-list algorithm which we have
adapted from our MD simulations can be used to greatly improve the
computational performance of wireless network simulators in the presence of
mobility, and illustrate with an example from our simulation studies of worm
attacks on mobile wireless adhoc networks.
