Mobile agent technology is a new paradigm of distributed computing, that models well some ofrnservices available in the net than other distributed computing approaches. Although thisrntechnology has generated considerable excitement in the research community, it has not beenrntranslated into a significant number of real-world applications due to a new dimensionality ofrnsecurity problems it brings along with it.rnMobile agents are programs that can autonomously migrate from nodes to nodes in a computerrnnetwork and perform a computation on the behalf of the user. It has a unique ability to transportrnitself from one system in a network to another. They work in conjunction with a mobile agentrnplatform which provides appropriate execution environment for the mobile agent. This platformrnneeds to be available at each potential host willing to entertain a visiting mobile agent. In thisrnthesis all the background information on the concept of mobile agent is given.rnThe security problem of mobile agent technology is of multidimensional. In this thesis the issuernof hostile host towards a visiting agent is given due diligence: Malicious host problem. It is onernof the most difficult problems to address. Threats emanating from malicious hosts are identifiedrnand a modified mobile agent computing model is proposed to prevent some of the threats. Thernproposed system design consists of components that provide support to the mobile agent while itrnis touring hosts in the agent space. It also protects the confidentiality and integrity of parts of thernmobile agent.rnKeywords: agents, mobile agents, malicious host problem, trusted nodes