Secure Service Discovery based on Trust Management for ad-hoc Networks

Abstract: In ad-hoc networks, mobile devices communicate via wireless links with-out the aid of any fixed networking infrastructure. These devices must be able todiscover services dynamically and share them safely, taking into account ad-hoc net-works requirementssuchas limited processing and communication power, decentralisedmanagement, and dynamic network topology, among others. Legacy solutions fail inaddressing these requirements.In this paper, we propose a service discovery protocol with security features, the SecurePervasive Discovery Protocol. SPDP is a fully distributed protocol in which servicesofferedbydevicescanbediscoveredbyothers,withoutacentralserver.Itisbasedonananarchy trust model, which provides location of trusted services, as well as protectionof confidential information, secure communications, or access control.Key Words: ad-hoc networks, service discovery protocol, security, trustCategory: C.2.2, C.4 1 Introduction Recent advances in microelectronic and wireless technologies have fostered theproliferation of small devices with limited communication and processing power.They are what are known as “pervasive systems”. Personal Digital Assistants(PDAs) and mobile phones are the more “visible” of these kinds of devices,but there are many others that surround us, unobserved. For example, todaymost household appliances have embedded microprocessors. Each one of thesesmall devices offers a specific service to the user, but thanks to their capacityfor communication, in the near future they will be able to collaborate with eachother to build up more complex services. In order to achieve this, devices in such“ad-hoc”networksshould dynamicallydiscoverand shareservices between themwhen they are close enough.In ad-hoc networks composed of limiteddevices, it is very important to min-imise the total number of transmissions, in order to reduce battery consumptionof the devices. It is also important to implement mechanisms to detect, as soonas possible, both the availability and unavailability of services produced when