The efficient design and implementation of advanced wireless networks is based mainly on the capabilities of the available simulation environments. Towards a reliable simulation, the developing and modelling methodology is a critical issue. Thus, high adaptability of the simulation model to the real network behaviour is a major goal. In a real wireless network (e.g. cellular), call admission, hand-off, call termination and user movement procedures take place at the same time for every individual user. Every network procedure acts autonomously, interacts with the network environment, takes decisions, etc. Due to that fact each network procedure can be faced as an agent inside a concurrent environment. Regarding this approach, the agent cooperation and communication is a critical issue too. A centralized multi-agent negotiation scheme based on a multi-agent layered concurrent architecture for designing and evaluating channel allocation strategies is herein presented along with the dependency of the simulation results on the rules and implementation methods of agent negotiation schemes.