:
. ( ). , - , . , , . - , .
. , . - , , .
. - . - . - ,
(host-to-host delivery)
(process-to-process delivery)
. 2.15.
3
. 2.16 . , () , - () j k (j k -). ( ) - , , - () ( . 2.16). - (j k, ). - (A P). - . , -
.. . 1 33 .. . 1 34
() .
, , -, .
(ApplicationLayer)
|
|
, ( ) . - ( SNTP POP3), ( FTP), WWW HTTP . - ( ) - . , , (message).
. 2.17. .
FTP FTP . 2.16.
, . () . , , , - - .
TCP UDP TCP/IP SPX Novell. - TCP UDP. , TCP (Transmission Control Protocol ), (, ) . , TCP , - . , UDP (User Data Protocol ), , .. ( ) . , UDP .
. 2.17.