A new design criterion for store-and-forward networks

Given the current network evolution path, the designer of a data, record, or stored-voice communications store-and-forward system, must generally piggy-back the latter onto an existing bona fide circuit-switched system. This implies relinquishing some ports on the circuit-switched machine to accomodate the store-and-forward system. These ports come at a premium and thus the intermachine link must be optimized in the number of trunks.

The normal design methodologies to obtain the number of trunks are reviewed; an improved approach based on the new concept of the “contrained average” is presented. The constrained average is a methematical construct which derives an appropriate equivalent traffic level L(f,ϵ), with L(f,ϵ) bounded below by the average of the traffic f(t) on an interval [a,b], and above by the maximum of f(t) in [a,b].