this book take a system-wide design approach to campus LANs. As such , we do not delve into details of implementation and configuration; presumably, readers are already familiar with such details for the applications and devices on their particular network . for the sane reason we also do not go into detail about the individual technologies, devices, and protocols that exist in campus network the connect here is developing the overall campus network to meet critical design goals; efficient traffic flow, resiliency security mobility and scalability