A method for distributing symmetric encryption keys in a communication system comprising a plurality of nodes is disclosed. Each node comprises information about printer control settings and printer jobs and a printing device configured for generating encryption keys. The method comprises: providing to each node an initial session key information that comprises an initial printer control setting and an initial printer job setting; providing to each node as a one-time pad an initial session key package encrypted with the initial session key information and comprising items of first session key information, wherein any two nodes have a common item of first session key information; generating at each node second session key information that is different for each of the other nodes; and sending from one of the nodes to another node a message encrypted with the first session key information and comprising the second session key information.