DHOP (Distributed Higher Order Processes) is a small programming language for distributed systems based on the behavioural paradigm of process calculi. It has modern features like static typing, first class processes, and a dynamically reconfigurable network topology. Unlike most of similar languages which also rely on message passing, DHOP enforces directed one-to-one communication channels between processes. A typing system using the idea of linear types allows statically to check this one-to-one condition. The soundness of the typing system can be shown based on the operational semantics that is defined by means of graph grammars.