WHAT IS PORT ?
In the Internet Protocol suit, a port is an endpoint of communication in an operating system. in software it is a rational construct that classifies a particular process or a sort of network service. And it is permanently related with an IP address of a host and the protocol type of the statement, and thus finalizes the destination or origination network address of a communication session.
Port is called called as a service delivered by a machine and each and every service running with a particular or customized port (The service is recognized by a port number). There are a lot of consistent port numbers for general services.
Ports is signified by optimistic (16-bit) numeral value between 0 and 65535
The port numbers are allocated into three ranges
- Well Known Ports 0 to 1023. Assigned & controlled by IANA.
- Registered Ports, 1024 to 49151. Not assigned & controlled by IANA.But registered by IANA.
- Dynamic and/or Private Ports, 49152 to 65535.Not assigned & registered by IANA
Some ports have been kept to provision shared / well known service.
- FTP 21/tcp
- Telnet 23/tcp
- SMTP 25/tcp
- SSH 22/tcp
WHAT IS SOCKET ?
A network socket is one endpoint in a statement flow in the middle of two programs running over a network, also it is maintaining and allow communication between two different processes on the same or different machines. socket address is the combination of an IP address and a port number.
In networking, a socket is used to allow many processes within a single or different host to use TCP communication simultaneously. The socket is formed by including the IP address with the port number to uniquely identify each separate data stream. A connection can be fully specified by the sockets at each end.
Also we call socket as type of a ‘tag’, that individually identifies and keeps a connection, such that request and reply are sent & received by the correctly mapped application running on a device.
Socket arrange for an interface for programming networks at transport layer.
TYPE OF SOCKETS
Associated to a remote active socket through an open data connection.
Closing the association terminates the active sockets at each point.
Associated, but awaits an incoming connection, which will brood a new active socket.
For more clarity , lets take an example – Think of your machine as an apartment building –
- A port is an apartment number.
- A socket is the door of an apartment.
- An IP address is the street address of the building.
Some of commonality between port number and Socket is shared below –
- Ports and sockets help identify process running on host machine uniquely.
- When a web page is terminated automatically , the socket programs will be terminated and associated port numbers are released back.