494     6   ________________________________

          -
  (Control Protocol),   IPCP, IPXCP  . .

 .     
     ,     -
        .
         .

   .      
 HDLC.      ,  -
      ,  ISDN, frame relay,
.25, Sonet  HDLC.

   LCP  NCP     -
  - . , ,    
 MTU  1000 ,        
   1500 ,    ,  
 -     .

      ,    -
 ,    ,     ?
          -
,     .      ( -
,       ) 
    ,    , -
     . , IP-    -
    ,       
 ,        .

       HDLC,     -
       HDLC.    -
     HDLC   .
        03.  
  ,   ,    -
 - TCP, SPX, NetBUEl, NCP  . .

       
      ,  
 .     , -
   MLPPP (Multi Link ).   -
         
 .     ,  
     .

         -
. ,        ,  
      frame relay.

6.2.4.     
 

         
     .   
 ,        , -