Abstract: The invention relates to a system and method for changing protocol parameters of a signaling protocol for the implementation of services in an Intelligent Network concept with user data transfer via a packet network. Resources are provided in a service control point for parameter changes to be made in the context of the services to the signaling protocol used. Implementation of a service, which requires a change to a protocol parameter in the signaling protocol, correspondingly adapted intelligent network application part procedures are used by a service switching point to trigger the parameter changes to be made in an service control point and the change to the protocol parameter is effected by the service control point in the service switching point. The invention has the advantage that it allows parameter changes, which are not provided in the ISDN user part because of their relationship with the packet network.