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THE BELL SYSTEM TECHNICAL JOURNAL, MARCH 1953 



0.01 

 8 



Q. 0.001 

 8 



0.0001 



Fig. 8 

 c = 1. 



20 

 t/h: 



30 40 50 60 70 80 



DELAY IN MULTIPLES OF AVERAGE HOLDING TIME 



Delayed traffic served in random order, exponential holding times, 



circuit system. The resultant delay distribution is shown as Curve B 

 on Fig. 7. (It is appreciated that this hardly represents a tolerable 

 normal operating situation, but rather illustrates what the performance 

 might be under extremely heavy traffic conditions.) The results are very 

 close to those obtained with perfect queueing (Curve C) and show in 

 striking fashion the gains in service to be made in certain delay situations 

 by providing a limited storage apparatus with a memory not subject 

 to confusion during moments of heavy overload. 



When the 1000 calls of Runs 1 and 2 are submitted to the 2 paths 

 through a simple gate in order to produce approximate queueing, the 

 resultant delays are shown by Curve D on Fig. 7. Large improvements 

 again occur in reducing the very long delays found with random handling. 

 In fact by use of this simple (and usually relatively inexpensive) gating 



