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New Member

Difference Between port no and protocol number

Hey guys,

can you illustrate the difference between port number and protocol number.

  • LAN Switching and Routing
4 REPLIES
VIP Purple

Difference Between port no and protocol number

HI Pankaj,

You can think of a port as a phone extension, with the computer's IP address being like its phone number. You can call the number (IP address) to talk to the computer, then dial the extension (port) to talk to a specific application. An application needs to be listening on a port in order to communicate.

A protocol is just the language that the two applications on either end of a conversation agree to speak in. If your application is sending streams of bytes to my application, my application needs to know how to interpret those bytes.

Regards

Dont forget to rate helpful posts.

New Member

Difference Between port no and protocol number

My question is that we say that protocol number for ospf is 89 and RIP works on UDP port number 520

what is the difference in these two protocol number and port number.

VIP Purple

Difference Between port no and protocol number

Hi Pankaj,

Port numbers are use by TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) while Protocol numbers are reserved number used to identify protocols.

PC-------Network ---------web server

For example: PC contact to the web server’s port 80 to get the web page because HTTP uses well known port number of 80. PC also use a port number from the User port range as the source port (e.g. 1380). This port number is used by the web server to serve the webpage to PC i.e. web server send the page with source port of 80 and destination port of 1380.

In an IP header, the Protocol field identifies the service in the next higher level in the protocol stack to which data is passed.

Hope it helps.

Reagrds

New Member

Difference Between port no and protocol number

hi,

A port is just a channel that you select for the communication, and the protocol determines how the communication is done.

In Simple port means to whom you want to communicate& Protocol means how to communicate.

ports = ears, mouth,

protocols = English, Spanish, Sign Language

Regards,

Guru

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