File:Bell telephone magazine (1922) (14753798904).jpg

Identifier: belltvol20elephonemag00amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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originating messages arehandled are called toll centers. Handling Interchanged Messages 1 HE relationships growing out ofthe exchange of millions of toll mes-sages between connecting companiesand Bell companies cover practicallyevery phase of the business. Onlythrough the closest cooperation is itpossible to coordinate the efforts ofboth groups so that a high grade oftelephone service will be provided.This involves not only the provisionof adequate plant, as to both gradeand quantity, but also the use of suchtraffic operating methods and routingsas will achieve speed and accuracy inthe handling of the messages to andfrom all points encountered in nation-wide service. Toll messages mayoriginate anywhere and likewise ter-minate anywhere, and the prompt andefficient handling of the millions ofsuch messages requires carefullythought-out operating methods andpractices. In order to achieve a universallygood telephone service on calls be- 90 Bell Telephone Magazine MAY 2 Toll(lenters-i Group
Text Appearing After Image:
.? Toll(lenlers-3 Groups 5 Toll (lenters- 10 Groups 7 Toll Cenlers- 21 Groups W Toll Genlers- ^45 Groups Fig. 3. Groups of Toll Circuits Required for Direct Connections betweenVarious Numbers of Toll Centers tween any two customers, regardlessof where they are located or whetherthey are customers of a Bell companyor a connecting company, it is neces-sary to provide toll circuits in suchnumbers and so arranged that satis-factory connections may be estab-lished quickly. Toll connections mayrequire operators at a number of tele-phone central offices along the routeto connect together toll lines in orderto build up the toll circuit between thecalling and called customers. Thesepoints of connection are referred to asintermediate switching points orswitches. Each additional switchintroduced in a built-up toll connec-tion increases the time required to es-tablish the connection and reducessomewhat the volume of speech trans-mitted. The telephone plant musttherefore be designed so that thesta

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