1、 2326434 0009078 4 W Type of connection Internal Originating Terminating Transit 63 T/S64-30 Page E 1 Reference Load A lo- 5 x 10-3 2 10-3 10- Recommendation T/S 64-30 (Edinburgh 1988) DIGITAL EXCHANGE PERFORMANCE DESIGN OBJECTIVES Recommendation proposed by Working Group T/WG 1 1 “Signalling, Prot
2、ocols and Switching” (SPS) Text of the Recommendation adopted by the “Telecommiciiicnrions“ Commission: “The European Conference of Post and Telecommunications Administrations, considering - that the achievement of long-term harmonization of integrated digital networks and integrated services digita
3、l - the importance of specifying performances requirements appropriate to the integrated digital network and networks represents a major target in the current development of the European network, integrated services digital network, recommends that the members of the CEPT, when introducing digital t
4、ransit, local and combined exchanges, take account of and give effect to the following performance requirements specifications.” The reader is referred to CCITT Recommendations 4.543 i, to which this Recommendation is identical, expert for the additions and modifications indicated below. The section
5、 references (indicated 5) are to 4.543 i. 52.1. Delete Note (2). 52.1.1, Replace with: 2.1.1. Reference Load on Incoming Interexchange Circuits (a) Reference Load A - 0.7 Erlang average occupancy on all incoming circuits with call attempts/hour/incoming circuit = 20. This figure assumes 25% ineffect
6、ive call attempts. (b) Reference Load B - 0.85 Erlang average occupancy on all incoming circuits with cail attempts/hour/incoming circuit = 25. 52.1.2. 52.2.1. Delete Note 1. 52.2.2. Insert after Table la/Q.543 the following note: “Note. PABX lines are assumed to have approximately the same trafic characteristics as interexcliange circuits have.” O Replace Table 2/Q.543 with the following table: REFERENCE i CCITT Recommendation 4.543. Reference Load B 4 x lo- 3 x lo- 2 x lo- lo- Digital exchange peiformnrice design objectives. Edition of January 15, 1989 ./- -
