The present document defines the stage 1 service description for phase 2 of the CTM service. Stage 1 is an overall service description, primarily from the service subscriber s and user s point of view, but does not deal with the details of the human interface itself. The present document includes information applicable to network operators and terminal, switch and database manufacturers. The present document specifies the requirements where the service is provided to the CTM user via a telecommunications network that is either the pan-European ISDN or a PSTN as provided by European public telecommunications operators.
The present document includes interworking requirements for cases where users in a call are located on different networks.
The provision of the CTM service on mobile networks is outside the scope of the present document.
The present document contains the core requirements for phase 2 of the CTM. A service may be provided on the basis of these core requirements alone.
The present document also documents some optional service features which may be used to enhance the service.
Furthermore, additional functionalities not documented in the present document may be implemented. The requirements of which are considered outside of the scope of the present document and consequently outside the scope of the corresponding stage 2 and stage 3 standards. Such additional functionality may be on a network-wide basis, or particular to one CTM user or a group of CTM users. Such additional functionality does not compromise conformance to the core requirements of the service.
Charging principles are outside the scope of the present document, unless specific service requirements are stated. These requirements deal with the allocation of certain call charges to particular CTM users. Interactions with services and ISDN supplementary services not listed in clauses 8 and 9 are outside the scope of thepresent document.The (...abbreviated)