FUNDAMENTAL PLANS FOR TOLL TKLKl'IIOXK PLANT 



849 



Table I— Approximate Range of Losses I^etwkkx '1'oll 

 Centers in db 



new metliods of m(>asiiriiig rosults will lead to marked improvements. It 

 is of some interest that one of the major factors in securing improvement 

 appears to be the application of a statistical method of evaluating per- 

 formance along somewhat the same lines as the "(juality control" methods 

 used in other fields of industry. 



Since, with operator toll dialing only one operator is involved in many 

 connections and with customer toll dialing there is no operator on the 

 connection it is extremely important that everything be right. This is 

 typical of the reciuirements of any large scale "push button" operation 

 (Fig. 12). 



conclusion 



The fundamental plans proposed for Telephone Toll Switching provide 

 a basis for the progressive mechanization of toll service. The installation 

 of suitable switching mechanisms at Control Switching Points and the 

 provision of toll trunks utilizing the new instrumentalities will implement 

 the toll switching plan. The plan is sufficiently flexible to adjust for 

 changes in the telephone art as they develop. Also, the plan can fit in 

 with the requirements of those Companies whose plants connect with 

 the Bell operating network should they desire to arrange for operator 

 or customer toll dialing. 



Average speed of service will be improved. The flexibility in plant 

 design inherent in the new toll switching plan will increase service 

 security and improve the utilization of the entire toll plant. In addition, 

 adequate provision is made for the progressive introduction of customer 

 toll dialing as this becomes practicable and desirable. 



bibliography 



1. H. S. Osborne, "The General Switching Plan for Telephone Toll Service," 



A.I.E.E. Transaclions, 49, pp. 1549 1557, 19,30. 



2. C. M. Alapes, "Carrier is King," Bell Tel. Mnq., 28, pp. 191 203, Winter 



1949-50. 



