Rec. ITU-T I.355 (03/1995) – ISDN 64 kbit/s CONNECTION TYPE
AVAILABILITY PERFORMANCE
FOREWORD
CONTENTS
SUMMARY
1 Introduction
1.1 Purpose
1.2 Scope
1.3 Abbreviations
1.4 Related Recommendations
1.5 Methodology of availability specification
1.6 Organization of this Recommendation
2 ISDN 64 kbit/s packet-switched connection type (PSCT) availability performance
2.1 PSCT availability function
2.2 PSCT availability parameters
2.3 PSCT availability objectives
3 ISDN 64 kbit/s circuit-switched connection type (CSCT) availability performance
3.1 CSCT availability function
3.2 CSCT availability parameters
3.3 CSCT availability objectives
4 ISDN 64 kbit/s dedicated-circuit connection type (DCCT) availability performance
4.1 DCCT availability function
4.2 DCCT availability parameters
4.3 DCCT availability objectives
Annex A – Sampling estimation of ISDN availability parameters
A.1 Estimation of the availability state of switched ISDN 64 kbit/s connection type portions
A.2 Procedure for estimating availability of switched ISDN 64 kbit/s connection type portions
A.3 Procedure for estimating mean time between connection portion outages of switched ISDN 64 kbit/s connection types
A.4 Statistical basis of Phase I minimal test with N = 4
A.5 Application of the sequential probability ratio test (SPRT) to the Phase I minimal test for availability
Annex B – Representative end-to-end availability performance of ISDN 64 kbit/s connection types
B.1 Representative end-to-end design availability performance of ISDN 64 kbit/s packet-switched connection type (PSCT)
B.2 Derivation of the end-to-end fi95th percentilefl availability from fiworst-casefl availabilities of connection portions
Annex C – Related availability parameters
Annex D – Factors to be specified in reporting ISDN availability performance of 64 kbit/s connection types
D.1 Planned hours of connection portion availability