TSPS No.1: System Organization and Objectives

At the outset of telephony, connections between telephones were established by operators through cords, plugs, and jacks at switchboards. Within the first decade, switchboard design and operating techniques soon settled into a pattern that is still followed today. The switchboards of SO years ago are remarkably similar to those commonly used today. (See Figs. 1 and 2.) With rapidly increasing traffic, it became apparent that to use operators to establish local calls was not the best way to continue. Dial switching was invented. Although the shift to local dial office operation started early in this century, it was in the years following World War II that the transition was rapidly completed. (See Fig. 3.) As the efficiency of transmission 2417 2420 TI-IE BELL SYSTEM TECHNICAL J O U R N A L , DECEMBER 1970 ORGANIZATION AND OBJECTIVES 2419 2420 TI-IE BELL SYSTEM TECHNICAL J O U R N A L , DECEMBER 1970 YEAR Fig. 3--Station growth.