Sprint Corporation and Subsidiaries, f.k.a. United Telecommunications, Inc. - Page 5

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               General Background                                                     
               Broadly, the three basic components of a telecommunications            
          system are station equipment, transmission facilities, and                  
          switches.  Station equipment is generally located on the                    
          customer's premises and includes such items as the telephone at a           
          residential customer's house.  Transmission facilities provide              
          the paths over which information is transmitted between customers           
          (whether the medium is used for local network transmission or               
          transmission over trunks, which are lines between different                 
          networks) and consist of transmission media such as copper and              
          fiber optic cable, as well as the equipment used to amplify and             
          regenerate the transmitted signals.  Switches connect                       
          transmission facilities at key locations and route incoming and             
          outgoing calls.                                                             
               The basic objective of the telephone switch is to connect              
          any calling outlet with any wanted inlet, a process that can be             
          visualized by picturing an operator sitting at an old manual                
          switchboard.  As a call is made, the operator pulls a flexible              
          cord connected to the caller's line and physically plugs it into            
          a receptacle connected to another line in the same network or to            
          a trunk line if the recipient is in a different network.                    
               The process of switching actually involves four sequential             
          phases, each consisting of certain activities or functions.  The            
          first phase, preselection, encompasses activities related to                
          recognizing a new call request and determining how to route it.             




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Last modified: May 25, 2011