1、CEPT T/CS*ZL-LZ*E 84 = 23264LY 0004b394 Page 1 (3 TCS21-12E Recommendation T/CS 21-12 (Montpellier 1984) CALL HANDLING FOR ALARM CALL SERVICES Recommendation proposed by Working Group T/WG 11 “Switching and Signalling” (CS) Text of the Recommendation adopted by the “Telecommunications” Commission: “
2、The European Conference of Postal and Telecommunications Administrations, considering - that alarm call services are supplementary services which are subject to harmonisation; - that the operational requirements for a number of such supplementary services are dened in the “Handbook on - that the ope
3、ration of those services when provided by a remote exchange requires the utilization of the “additional - that provision of such services by a remote exchange may be economically advantageous in the case of small local services and facilities offered to the subscribers in modern telephone systems” i
4、; signalling feature” as defined in Recommendation T/CS 20-26 2; exchanges, O recommendr to members of the CEPT to adopt for the call handling of alarm call services the requirements as described below.” 1. The SF Handbook provides operational requirements for the following supplementary services be
5、ing members of the “Alarm call service” family: - Service 2.1.3.: - Service 2.1.4. : - Service 2.1.5. : - Service 2.1.6. : Alarm call services, automatic, casual; Alarm call service, automatic, regular number of consecutive days; Alarm call service, automatic, regular specified consecutive days of c
6、alendar week; Alarm call service, automatic, regular specified programme of days. 2. Alarm call services can be provided either by the local exchange to which the user is,connected, or by a remote exchange. In both cases, the providing exchange should be equipped with the feature “Real time clock” a
7、s specified in Recommendation T/CS 20-18 3. 3. In the case where an alarm call service is provided by the local exchange there will be no specific requirements for interexchange call handling. 4. In the case where an alarm cail service is provided by a remote exchange, interexchange call handling wi
8、ll take place: (a) for the supplementary service control procedures, (b) for operation of the alarm call service. 5. The requirements for call handling for control of remotely provided supplementary services are laid down separately in Draft Recommendation T/CS 21-11 4. 6. When a call is set up due
9、to the operation of an alarm call service from a remote exchange to the user, this cail should be class marked as being an alarm call. For example, this class marking is required as the alarm call should override any incoming call barring supplementary services activated for the user to which the al
10、arm call is destined. Compatibility requirements with “call diversion” and %ail waiting” supplementary services have been identified as well but they still require further study. 7. According to the considerations and requirements described in the previous paragraphs, the following service instructi
11、on should be established for alarm call services provided from a remote exchange: Alarm call A forward service instruction sent together with the call Set-up information, indicating that the call is made due to the operation of an alarm call service. O Edition of May 15, 1986 - CEPT T/CS*23-32*E 4 =
12、 2326434 0004640 O TICS 21 -12 E Page 2 References i CEPT Handbook on services and facilities offered to the subscribers in modern telephone systems. Prepared by CEPT Working Group SF. 3rd edition 1981. 2 CEPT Recommendation T/CS 20-26. Additional signalling. 3 CEPT Recommendation T/CS 20-18. Real time clock. 4 CEPT Draft Recommendation T/CS 21-1 1. Control of remotely provided supplementary service (contained in Annex 4 to CEPT document T/CS (84)93: “Call handling sequences for supplementary services call handling”, working document November 1984).
