The application concerns a method for invoking a communication service that is realized by means of a peer of a peer-to-peer system, the method comprising the step of identifying a peer hosting the communication service and invoking the communication service by means of a distributed directory, where the distributed directory carrying entries that enable a client to invoke the communication service, the method further comprising the step of identifying an alternative peer hosting an alternative communication service in case the identified peer or the communication service is unavailable, where the distributed directory carrying entries that enable a client to invoke the alternative communication service. And the application concerns a computer software product and a telecommunication system for providing communication services corresponding to the method.