458     6   

  Internet.   ,  
Internet,  .      Web-
     ,   
   ,     , 
     , -
  ,     chat, -
    ( News),     
     .

  (  )    
    ,      ,
   ,   -
  Internet,    ,    
   chat,      
  .

  Internet     
   ,      
 .       -
       Web--
,       
,      .  -
   intranet,     ,  
Internet    .   intranet  
  Web,    Internet   
,    ,    
  ,    Internet  -
    .

          -
        .

        -
 ,       . -
 ,         
    .

  

        . 6.2.
   : S (switch)  ,   -
, R (router)  , MUX (multiplexor)  , UNI
(User-Network Interface)    -   NNI (Network-Network
Interface)    - .  ,    -
 ,       DCE,  
  .

     ()  , -
      .  
    (),     -
 ,          
  ,  (cell).       -
      ,    -