Jerry is the project manager for a team developing a retail store management system for a chain of sporting goods stores. Company headquarters is in Las Vegas, and the chain has 27 locations throughout Nevada, Utah, and Arizona. Several cities have multiple stores. Stores will be linked to one of three regional servers, and the regional servers will be linked to corporate headquarters in Las Vegas. The regional servers also link to each other. Each retail store will be outfitted with similar configurations of two PC-based point-of-sale terminals networked to a local file server. Jerry has been given the task of developing the architecture design and hardware and software specification for a network model that will document the geographic structure of this system. He has not faced a system of this scope before and is a little unsure of how to begin. What advice would you give?