N-GEN Communications Web-based Seminars ©NGCS

Seminar - An Overview of Communications Technologies

Module 6 - Internet, Intranet, Extranet, e-Commerce and Web Services                                      Slide 25 of 70 _________________                                                                                  __________

                                                 Sockets and Ports

                                            Host-to-Host Connection

                                            Sockets

                                            Ports

_________________                                                                                  __________

Sockets and Ports are used by both TCP and UDP for applications on the sending computer to communicate with the applications on the receiving computer. When a host creates a connection with another host to access a perticular service, an end-to-end connection is set-up, and a socket is created at each end of the connection. It is like two people using a radio system selecting a band to communicate. To communicate on a radio two people must tune in to a channel. A Port is like a channel on the radio.

Well Known Ports:

A browser client knows that while accessing a Web server it should pass a particular inbound segment to the HTTP service.

Ports: There are three types of ports: Well Known Ports, Registered Ports and Dynamic and/or Private Ports. The Well Known ports are from 0 to1023, the Registered Ports are from 1024 to 49151 and the Dynamic and/or Private Ports are from 49152 to 65535.