5.3.  IP     391

  ,   RIP.   -
    -     
 ,       ,   
 .   Unix-   -
,   ,      RIP.

      Unix-.  -
  .

 U  ,     .  
  Status   NetBuilder.

        .  
 ,     ,    
.

 G  ,       -
 (gateway).      -
 .

 D  ,      Redirect ()
 ICMP.        -
  .  ,     -
        -
     ,      
ICMP ,         
   .  ICMP   -
  -,    
    .       -
,       .
  Unix-    ,  -
 .  Refcnt ,      -
   .  Use   ,
   .

   NetBuilder     .
   TTL (Time To Live)     -
,     .    
     .  Source   -
    .        -
,        
    .

      

      TCP/IP.  -
      
   ,       -
  .

, -,       -
  ,         -
    .    
      213.34.12.0  198.21.17.0,  