 Radius,     . 
Cisco       TACACS/TACACS+
(Terminal Access Controller Access Control System     
  ).

         RAS (Remote Access
Server        ,  
     ).    RAS, , -
    ,  ,      -
  .

           
( RAS,      ).    -
 :        .  
           
.      "  ".    
   ,    .  
        .  
         -
  RAS.

   ,     ,  CLID
(Caller Line ID    )   ( -
 ).         
      .    
,   CLID    .

  

   UNIX/Linux  / Bliss,   1997 , 
 RST.b,    2001 .     
  Web.    ,   -
.   Bliss  RST.b      
Linux   ELF.

2  1988 ,   17:00 -  
 .- (Robert . Morris Jr.)   Internet   -
 .     Internet-     
      Internet.      -
   ,   ,      
finger.          
   .      Internet,    -
  36 ,     .

       ,
  Internet.  ,     , 
        , 
  root,        -
 .

    UNIX  Linux     . 
      Windows NT.    
    ,      -

946                                                         VII. 