Modern train systems generate vast amounts of data. Analysis of this data may sometimes not be performed on the running train, and must be transmitted to other systems operated by the train management. The ability to transfer information to and from trains is often dependent on imperfect communication channels, such as mobile phone networks. Accordingly, there is an immediate need for an effective, robust and secure communication framework to abstract away these considerations from the information producers and consumers. This project attempts to define a framework for reliable data communication using unreliable communication channels, interacting with existing train systems. The result consists of a prototype design and a .Net implementation of such a framework, as well as a generic and extensible type library corresponding to the types of data generated by the Flytoget train system. Furthermore, several performance tests were undertaken; it is shown that while the use of such a framework may be detrimental on bandwidth usage, this negative impact may be lessened by the use of compression and message batching. The results presented in this thesis will be of general use on modern train systems, while the prototype was designed specifically for Flytoget.