Abstract: In a method for providing a service between a service unit and terminal devices of at least one communication network, a synchronization unit evaluates the service provided by a service unit with respect to at least one technical requirement for use by at least one terminal device, establishes at least one rule for exchanging data of the service in accordance with the evaluation result, and stores the evaluation result. The synchronization unit forwards information regarding a registration for a service to at least one network unit of at least one communication network, with which a user of the terminal devices is registered. Upon inquiry by a terminal device for provision of the service through the service unit the synchronization unit exchanges the data via the synchronization unit in accordance with at least one established rule that depends on the technical requirements of the inquiring terminal device.