240_________________________________________ Internet

     ,  ,
   ,   -
     TCP  UDP.

   "" WWW-   SSL
(Secure Sockets Layer),    
 ,    ,  
. SSL     -
,      HTTP,  , , FTP 
SMTP. SSL       RSA,
DES  MD5,          
 .     -
 HTTP     .

 HTTP  CGI-

CGI       .
 ,     CGI    WWW-,
  ,  CGI-   , 
  1993     HTTP-,  
    .   HTTP-, CGI-
        -
      .    
 HTTP-,  CGI     -
        HTTP.

,     URI,   CGI-.
  , HTTP-   (  -
),     CGI-,    -
 HTTP        CGI-
.

       
  CGI-  ,   -
  HTTP-.

 AUTH_TYPE     (  
).    "Authorization:"  "Request-
Header"

 CONTENT_LENGTH    .  
"Content-Length:"  "Entity-Header"

 CONTENT_TYPE     .  
"Content-Type:"  "Entity-Header"

 QUERY_STRING     URI . , 
 URI     : "scheme ://host:port/