ÿWPCL ûÿ2BJ|xÐ ` ÐÐÌÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿH øÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÌÐÐ °°°è ÐÑ Âx„|ü@Ž ÑÐ Å°6Ø'°6Ø'Å ÐÓÓÃÃRecommendation I.220 © Common dynamic description of basicÄÄ ÃÃtelecommunication servicesÄÄ 1.ÁHÁÃÃIntroductionÄÄ Ð  ÐÁHÁThis Recommendation provides the dynamic description of basic telecommunication services. The dynamic description for basic telecommunication services using the circuit©mode means of service establishment/dis©establishment is provided in section 2. The packet©mode description is for further study. Ð X ÐÁHÁThe dynamic description shows the flow of events, and states within the service, in a time sequenced format and identifies all possible actions relevant to the service as perceived by end©users. ÁHÁAlthough the service is described from the end©user perspective it does not concern details of the human©to©machine interface itself. In addition, the service description considers the network as a single entity. For example, information flows between nodes within the network are not shown. ÁHÁEnd©user perceptions of the service are shown in terms of "user/network" interactions. Internal network actions are included whenever they are or can be perceived by an end©user(s) during the operation of the service, and as required by SDL drawing rules. ÁHÁThe terminology and the meaning of the "user/network" interactions are provided in Annex A. The means for developing dynamic descriptions, e.g. the SDL symbols and their usage, is further elaborated in Recommendation I.210. ÃÃNoteÄÄ © In the development of the circuit©mode dynamic description, the bearer services © speech, 3.1 kHz audio, unrestricted, and the teleservices © telephony, Teletex, Telefax 4, mixed©mode and Videotex were considered. Others are for further study. 2.ÁHÁÃÃCircuit©mode dynamic description ÄÄofÃà basic bearer and teleservicesÄÄ (BASIC CALL PROCESS) Ô ñ,ÔŒ (BASIC CALL PROCESS Macro definition outgoing call) ÃÃNote 1ÄÄ © This is an event which may occur at the S/T reference interface and can be reflected at the user interface. (BASIC CALL PROCESS MACRO DEFINITION INCOMING CALL) Ô ñ,ÔŒ ÃÃNote 2ÄÄ © This is an event which may occur at the S/T reference interface but is not reflected at the user interface. Ô ñ,ÔŒ Ô ñ,ÔŒ ÁàÀMÁANNEX Aƒ ÁàÀDÁ(to Recommendation I.220)ƒ ÁàÀPÁƒ ÁàÀ;ÁÃÃTerminology for "user/network" interactionsÄă ÂHHÂÂX  ÂÂX øÂÁ€  ÁÁ€ HÁÁ€ÁÁHÁSETUPÁ øÁÁpÁ Interaction across the "user/network" interface regarding a service request.ÆÆ ÁHÁREPORTÂà ø Interaction across the "user/network" interface regarding alerting of the users terminal function, interworking with a non©ISDN network, or routing progress.ÆÆ ÁHÁCONNECTÂhø Interaction across the "user/network" interface regarding completion of circuit cut©through.ÆÆ ÁHÁDISCONNECT Interaction across the "user/network" interface ÂHHÂÂX  ÂÂX ø  regarding a user who has disconnected or user A cannot be   connected (e.g. Busy) to user B.ÆÆ Ð ` Ð Ð H ÐÁHÁRELEASEÁøÁ Interaction across the "user/network" interface regarding freeing of resources associated with the call/connection, such as call references and channels. ÁHÁNDUBÁ øÁÁpÁ Network determined user busy. ÁHÁUDUBÁ øÁÁpÁ User determined user busy.