Design and Implementation of a Service Discovery Architecture in Pervasive Systems

The availability of cheap wireless technologies, which can be interconnected through the Internet, has paved the way to a large fruition of (web) services and the convergence of the Internet with mobile handheld devices. A potential market opportunity could become concrete only if users can easily locate and access the available services, thorough support for Service Discovery. There are a number of service discovery protocols and architectures incompatible with each other and sometimes applicable to only specific networks. Often the use of these protocols can be carried out only by experienced users. In this article we will describe an architecture implementing Service Discovery for a Pervasive System, which is simple, effective and compliant with standardization. Whenever a generic user, equipped with his wireless or wired terminal, get access into an IP Network, the Service Discovery service start up finding all the available and suitable services which can be accessed locally or remotely from that access point. This work has resulted in the context of DAIDALOS (Designing Advanced network Interfaces for the Delivery and Administration of Location independent, Optimised personal Services [1]), a project granted in the European 6th Framework Research Programme, within the IST (Information Society and Technology) thematic area. Index Terms – Service Discovery, Service Location Protocol, Pervasive System, Personalization, Context Awareness. I. SERVICE DISCOVERY henever services are to be located in a LAN or in the Internet, Service Discovery has to be performed. In order to enable automatic Service Discovery mechanisms, some protocols and software architecture have been proposed (SLP [2,3,4], JINI [5], UPnP [6], Salutation [7], UDDI [8], SDP [9] ecc.). Compatibility, autonomy, and simplicity of service discovery are important requirements for applicability in pervasive systems. Each Service Discovery solution is characterised by an architecture, a service description model to define service characteristics and rules for filtering and allowing service selection. Existing solutions are often not compatible with each other, in terms of architecture, description model and rules. In this work we propose a general architecture independent from the particular Service Discovery Protocol, which can perform Service Discovery both in automatic or manual mode, into a pervasive system. We then show a practical implementation based on SLP, which is an IETF standard protocol.