In my thesis I focused my work on analysing and developing a working prototype of a remote maintenance system for a military weapon system. The diagnostic system DS is an application which is developed by Diadrom Holdings for diagnostic and maintenance of the Saab Dynamics weapon system WS. The possibility of remote maintenance was analysed with a focus on the connection limitation of using Satellite or military radio. The analysis needed to determine what functionality that could be used in a remote scenario. The analysis was made as a basis for making a concept. The concept was a solution to lower the cost of maintenance of the weapon system. The idea was to make a structure which would use NAT traversal with UPnP. I developed an extension of the existing diagnostic system and verified it by connecting to a simulator of the weapon system. The connection limitations were not a problem for the implemented prototype.