The reliability of holding time measurements

ONE of the fundamental quantities in traffic engineering is the average duration of subscribers' calls. This figure in seconds multiplied by the average number of calls expected over a given route in an hour, and divided by 3600, gives the traffic load submitted in average simultaneous calls — or “the average” as it is commonly called. Tables and curves are widely available which may then be consulted to find the number of paths to be provided so that no more than a desired small percentage of the calls presented will find all paths busy.