The problem of securing Ad Hoc networks represents a serious challenge. This is due primarily to the open nature of a MANET environment which relies on the air interface as being the medium of transmission of all traffic. In this context, MANETs inherit all vulnerabilities of traditional wireless technologies. To establish a data transmission between two nodes, typically multiple hops are required due to the limited transmission range. Mobility of the different nodes makes the situation even more complicated. Multiple routing protocols especially for these conditions have been developed during the last years, to find optimized routes from a source to some destination. The scope of this book is to test routing performance of six different routing protocols (AODV, DSR, LAR 1, ZRP, Fisheye and LANMAR) in variable network sizes up to two hundred nodes using QualNet Simulator from Scalable Networks to perform the simulations.