Abstract This paper discusses how ad-hoc collaboration boosts the operation of a set of messengers. This discussion continues the research we earlier initiated in the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}MESSENGER\end{document} project, which develops data management mechanisms for UDDI registries of Web services using mobile users and software agents. In the current operation mode of messengers, descriptions of Web services are first, collected from UDDI registries and later, submitted to other UDDI registries. This submission mode of Web services descriptions does not foster the tremendous opportunities that both wireless technologies and mobile devices offer. When mobile devices are “close” to each other, they can form a mobile ad-hoc network that permits the exchange of data between these devices without any pre-existing communication infrastructure. By authorizing messengers to engage in ad-hoc collaboration, collecting additional descriptions of Web services from other messengers can happen, too. This has several advantages, but at the same time poses several challenges, which in fact highlight the complexity of ad-hoc networks
