IP telephony over mobile ad hoc networks is a topic of emerging interest in the research arena as one of the paths toward the fixed-mobile convergence in telecommunications networks. To investigate the performance characteristics of this service, we propose a complete system architecture, which includes a MAC protocol, a routing protocol, and the treatment of voice packets. The telephone system is analyzed in the case of point-to-point calls inside the ad hoc network, and the endto-end performance is assessed in terms of the percentage of blocked and dropped calls, packet loss, and packet delay. The analysis takes into account network scalability by investigating how the size of the multihop ad hoc network impacts the quality of service. Moreover, the synthetic mean opinion score of the telephone service is evaluated according to the ITU-T E-model. Quality of Service for Packet Telephony over Mobile Ad Hoc Networks n mobile ad hoc wireless networks, multiple mobile stations communicat...