Thomas Kunz
Systems and Computer Engineering
338
Ports and Sockets
nCommunications through the Internet occurs between a
"Client" application software and
the same application software running on a "server"
nEach connection is uniquely identified by 4 addresses:
(1) Client IP address, (2) client
application port #, (3) server IP address and (4) server application port.
nApplication ports on the server side are called:
"Well-known Sockets". The port number for each application is known to all
hosts
Application
Application
Application
Application
Application
TCP
IP
TCP
IP
TCP
IP
Application
ports
ports