154                                                                Internet

  

        -
       , 
      :

1.      .     -
 ,    HOSTS.TXT, . .  
         IP-
, .    DNS       
 RR  "".

2.      .  ,   
 HOSTS.TXT    :   
   IP-     . 
 DNS   ,   "IN-
ADDR.ARPA"  PTR. ,       1.2.3.4
   , RR  PTR   "4.3.2.1. IN-
ADDR.ARPA".

3.  .      -
           
.        QNAME,
QTYPE  QCLASS.    ,  -
 .

        
( RR  ),    (,   -
   ),  ,    
(,   ,     ).



      ( 2) 
  :

D SNAME   
 STYPE  QTYPE 
 SCLASS  QCLASS 

 SLIST  ,     ,   -
    .   -
    , , , -
   .

 SBELT  ,   SLIST.    
    ,   -
,        -
    .

D CACHE       .