28
NAT (Network Address Translation ) TCP/IP, IP- .
NAT , , . SNAT, (. source) (. destination) . / .
, IP- . , . , . , . IP- . , , n- .
3 :
(Static Network Address Translation),
(Dynamic Address Translation),
(NAPT, NAT Overload, PAT).
NAT IP- IP- . , .
NAT IP- IP-. NAT , , , .
NAT (NAPT, NAT Overload, PAT, ) NAT, IP-, . PAT (Port Address Translation). , .
NAT .
1. IP- ( NAT PAT), IP- IP- ( , , ).
2. ,
3. /. , , (, 80- TCP (HTTP-) 54055-). , , IP- ( ) http://example.org:54055, , NAT, 80- . .
|
|
1. NAT. , .
2. - .
3. , , , . , NAT- , , Universal Plug & Play, .
IP IP-
gateway
, IP-
IP-
IP-, IP-.
IP-.
.
NAT . .
NAT . ( NAT) NAT ( ).
29
(Wide-Area Network, WAN). .
:
" - " (point-to-point);
"" (cloud).
N N(N - 1)/2
WAN "". .
"" :
( );
( E-mail);
( IP, X.25), ( Frame Relay), ( ATM).