%0 Journal Article %T Multiagent Systems Protection %A Antonio Mu£żoz %A Pablo Anton %A Antonio Ma£ża %J Advances in Software Engineering %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/281517 %X Agent-systems can bring important benefits especially in applications scenarios where highly distributed, autonomous, intelligence, self-organizing, and robust systems are required. Furthermore, the high levels of autonomy and self-organizations of agent systems provide excellent support for developments of systems in which dependability is essential. Both Ubiquitous Computing and Ambient Intelligence scenarios belong in this category. Unfortunately, the lack of appropriate security mechanisms, both their enforcement and usability, is hindering the application of this paradigm in real-world applications. Security issues play an important role in the development of multiagent systems and are considered to be one of the main issues to solve before agent technology is ready to be widely used outside the research community. In this paper, we present a software based solution for the protection of multiagent systems concentrating on the cooperative agents model and the protected computing approach. 1. Introduction In the area of information systems, security is one of the most interesting topics. Recently, with the huge growth in the number of distributed systems, the number of computing attacks has increased and therefore so has the number of protection systems. The first work done on software agents was in the mid 1970s by Hewitt and Baker [1]. Hewitt created an agent model (named Actor), which he defined as an autonomous object that interacts and executes concurrently with an internal state and communication capability. Since that initial conception, and due to the work developed in Distributed Artificial Intelligence (DAI), a new concept has arisen known as the Multi-Agent System. The main appeal of these systems is that they allow two or more entities to join forces to perform a common task, which is very difficult to complete individually. Nowadays a huge variation of software agents exists according to their features, abilities, or properties. Mobile agents are implementations of remote programs, that is, those programs developed in a computer and distributed in other computers to continue their execution [2]. The migration capability provokes different security risks and makes controlling the following aspects essential: the protection of hosts against agents and the protection of agents against the host and authors to define the network protection. The firsts MAS applications appeared in the middle of the 80s. These first systems covered a wide variety of environments (manufacturing systems, process control, air traffic control, information %U http://www.hindawi.com/journals/ase/2011/281517/