In this paper, the boundary effect in multimedia TDMA personal mobile communication network simulation is investigated. We evaluate the performance of several Channel Assignment Strategies (CASs) for multi-rate traffic calls in a Manhattan-like microcellular environment under two different simulation topologies. These are the wrapped around topology, which minimize the boundary effect, and the unwrapped topology, which ignore it. Both, uniform traffic and uneven time varying traffic are considered. Also, the user mobility is taking into account. The CASs evaluated are the Maximum Packing (MP) algorithm with cluster channel reservation (CCR) and the Extended Local Packing (ELP) algorithm. The ELP is a practical distributed dynamic CAS that approaches closely the system capacity of the MP with CCR algorithm. Simulation results obtained using the unwrapped topology compared to those obtained using the wrapped one differs no more than 2%.0-7803-7005-8/01/$10.00 0 2001 IEEE