Abstract:        This paper presents MANET-VoVON, a new Internet application for mobile ad-hoc networks (MANETs) providing voice over virtual overlay networks. A MANET-enabled version of JXTA peer-to-peer modular open platform (MANET-JXTA) is used to support user location and optionally, audio streaming over the JXTA virtual overlay network. Using MANET-JXTA, a client can search asynchronously for a user, and delay the call setup until a path is available to reach the user. The application uses a private signalling protocol based on the exchange of XML messages over MANET-JXTA communication channels. Nevertheless, it is fully interoperable with normal SIP clients through an embedded gateway function. This paper describes a prototype implementation of the proposed application and of the MANET-JXTA, and presents some performance measurements.