A method of providing a new network service to selected subscribers, who are already receiving known network services, uses labels. A distinct label is assigned to each network service and is also attached to subscribers already receiving that service. To access newly selected subscribers for providing a further service or a notification, the method uses predetermined subscriber-access-labels which lead to a class of intended subscribers. The intended subscribers are listed by using the subscriber-access-labels and a label-matching-algorithm in a flat hierarchy to generate a list of the newly selected subscribers. The list assists to dispense either a new network service or otherwise to reach them. Label matching also enables producing a desired list of specified network services. A computer readable medium for the method is included. The present method enables faster service by avoiding a largely hierarchical approach to retrieving customer listings, and is well suited for applications like AJAX®.