Mobile ad-hoc networks are continuously self-configuring infrastructure-less network of mobile devices. The ad-hoc term means « for this situation ». Publications usually do refer to such systems with the MANET acronym for Mobile Ad-hoc NETworks. Their internal operations enables exchange of information in infrastructure-less environments. The management of data packets is shared among different devices undertaking one after the other routing operations. This document deals with the issues related to these systems, their principles, architecture, operations and industrial applications implemented. For a better understanding of their process, OLSR, AODV and ZRP routing protocols are partially presented. Future prospects of these systems are addressed with future mobile phone networks and tomorrow’s vehicular networks also called VANET for Vehicular Ad-hoc NETwork. In order to better understand the challenges of futures VANET networks, one model proposal for carriage packets based on quality of service routing path and ant colony optimization algorithm is presented.