Chapter 6. Accessibility

  1. William C. Hardy

Published Online: 18 APR 2002

DOI: 10.1002/0470845910.ch6

QoS: Measurement and Evaluation of Telecommunications Quality of Service

QoS: Measurement and Evaluation of Telecommunications Quality of Service

How to Cite

Hardy, W. C. (2002) Accessibility, in QoS: Measurement and Evaluation of Telecommunications Quality of Service, John Wiley & Sons, Ltd, Chichester, UK. doi: 10.1002/0470845910.ch6

Author Information

  1. WorldCom, USA

Publication History

  1. Published Online: 18 APR 2002
  2. Published Print: 1 JUN 2001

ISBN Information

Print ISBN: 9780471499572

Online ISBN: 9780470845912

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Keywords:

  • accessibility;
  • availability;
  • encoding overhead;
  • effective capacity;
  • handling overhead;
  • MTBO;
  • mean time between outages;
  • MTBOSI;
  • outage;
  • outage latency;
  • service interruption;
  • throughput efficiency

Summary

Describes the origin and nature of user concerns with ability to use a telecommunications service when needed. Defines a generic measure, accessibility, that reflects users' exposure to inability to use a telecommunications service, rather than service failures. Recommends Operating Characteristic Curves (OCCs) for Mean Time between Service Interruptions (MTBOSI) as the most meaningful quantifier for accessibility of intermittently used services and Operational Effective Capacity (OEC) for continuously used services. Displays the mathematical relationships between OCCs for MTBOSI and Mean Time between Outages. Shows how to calculate the OEC as a function of its various components, such as connection availability, throughput efficiency, and various overheads. Associated Appendix B explains why availability is a singularly inappropriate measure for addressing this concern.