However, little is known about how to optimize the design - almost all the problems of work to optimize the flow of a given design assumptions. Basic book handling optimization network structure itself, comes to understand the design principles and realistic. With the level of fixed costs, the model implies a natural class of optimal source-destination connections directly, but consideration of variable load and environmental intrusion and then enforce the trunking in the optimal design, produce clean arteries or hierarchical. Connections are made with admirable job of degree? Dn Sigmund on optimal mechanical structure and also with neural networks, processing and communications, including Internet and Worldwide Web.