Talk:TCP and UDP port

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"Note that not all transport layers use network ports; for example, although UDP and TCP use ports, ICMP does not." - Thought ICMP was a network layer protocol

/H

Contents 1 Ports Analogy 2 Common Ports 3 Clarification 4 Not all transport layers use network ports

[edit] Ports Analogy

A lot of the people I explain ports to don't really it get it unless I give them some kind of analogy. I find this one quite affective but I'd like some input before I put it on the main article.

"Think of IP addresses and ports as a block of flats, or a university hall of residence. The IP address relates to the address of the actual block of flats as a whole, and the port number relates to the flat number within the block. If a letter (A data packet) is sent to the flats (IP) without a flat number (Port number) on it then nobody knows who it is for (which service it is for). In order for the delivery to work, the sender needs to include a flat number along with the address of the flats to insure the letter gets to the right destination."

Noopectro 17:58, 28 March 2007 (UTC)

I agree that analogies could be useful for this page. Even after reading the analogy above, I'm still fuzzy on TCP ports and sockets. The words themselves, 'port' and 'socket', invoke images of hardware connections, like USB ports and electrical sockets. Computers have plenty of physical ports and sockets, and a noob like me wonders if there are some tiny sockets on the motherboard or something (I know there aren't; there are, what, 9000 + sockets or something?).

I don't know if it's possible to come up with an analogy that would explain ports and sockets in the context of an operating system or other software, or even if OSs / software are relevant to this discussion. But for an encyclopedia article aimed ostensibly at a general readership, this one seems to take a lot of technical understanding for granted.

Why can't the computer just send the data to every port? From a brute force perspective 65000 seems insignificant. I wish it could determine automatically by sending to all them, and then the program responds when the matching program is found. I guess what I'm getting is "Do I have to port forward for every internet application when a router is introduced to my connection?" 206.248.174.127 (talk) 06:30, 6 January 2008 (UTC)

[edit] Common Ports

List of common ports? Seems relevant to me. If no objections, will add some ports from IANA published list (only ones in common usage by Joe Public). Tswsl1989 15:51, 9 May 2007 (UTC)

Please, just link to List of TCP and UDP port numbers. Multiple lists of this type tend to grow in different directions from each other... DStaal 14:23, 10 May 2007 (UTC)

Couldn't find a list on wikipedia when I looked for one. Thanks for pointing it out Tswsl1989 10:16, 13 May 2007 (UTC)

[edit] Clarification

What happens when one system has several IP's?

Each IP can be used or use the same port numbers?

Will those ports be different for different IP's?

I guess both answers are "yes".

Do not forget that an ENDPOINT of a communication link is still a Sockets that consists of a Port AND an IP adress —Preceding unsigned comment added by 87.159.110.4 (talk) 09:37, 24 January 2008 (UTC)

[edit] Not all transport layers use network ports

The article says

Not all transport layers use network ports; for example, although UDP and TCP use ports, ICMP does not.

However ICMP does not belong to the tranport layer. How can we rephrase this ? —Preceding unsigned comment added by 82.229.209.33 (talk) 13:51, 7 January 2008 (UTC)