The author (Tatu Ylonen) sent an email to Joyce K. Reynolds at IANA, on release of v.1.0 of SSH protocol, and IANA agreed to assign port 22.
That's kinda it.
A summary of SSH use follows the story which is a good overview for someone new to it.
What has changed is that there is essentially no chance of getting a privileged port allocated now.
One of the side effects of them being such a widespread and networked group is that when I made my application, they suggested I go talk to one of my coworkers (as loosely defined as that is at Microsoft) since he helped standardize the body anyhow. A bit of zen - "the answers you seek were within you[r org chart] the whole time"
1. https://www.iana.org/assignments/service-names-port-numbers/...
(Update: s/network/company/
I doubt they had all that many networked computers at the time, but fuzzy memories of a third-hand story.)
Things were considerably more casual in the 90s...
https://en.wikipedia.org/wiki/Request_for_Comments
"Unlike the modern RFCs, many of the early RFCs were actual requests for comments and were titled as such to avoid sounding too declarative and to encourage discussion"
Its just an informal agreement. Its just a 16bit number.
There are certainly cases of different software using the same unprivileged ports by default. It's probably more rare for the privileged ports.
Whats the big deal if you run ssh on port 443 as many do, together with nginx on the same port?
Or if you run a web-server on port 22 and irc on 21.
The deal is that if we're talking of TPC apps on a single network interface, you can't.
The deal is also that it's handy to know where you can expect to see a common service running.
No, but you can fake it with sslh: http://www.rutschle.net/tech/sslh.shtml
I recall the feeling I got the first time I sent a message to the Nessus mailing list. I couldn't compile the program so I was asking for help.
I thought I was going to wait for a long time, but was surprised when a response came a few minutes after. The response came from the author of the program itself, and he was very nice in how he answered my question. It was obvious that I was a noob and needed hand-holding. It made a lot of difference to me.
You have no idea how that positive response affected Tatu.
Edit: Changed possible to positive in the last paragraph.
I blogged about this at http://verticalsysadmin.com/blog/cfengine-is-awesome/
I wonder if the creator of ssh thought that he/she would still be working on it in 2017.
You'd be surprised in how interesting me and other find this story.
Of course if you grew up talking all these for granted, and don't have an interest at how things were back then, it might not be.
But there are tons of interesting stuff in this short post, including the informality of how SSH started.
Bit pejorative there.
I find it more "huh, nice to know" rather than "wow, I'll tell my friends"; I'll hand in my rainbow books on the way out ...
I've been using the internet since one could decide how to route the emails one sends, I've used SSH a lot: it's just not interesting as a story, it's barely a factoid.
FWIW I think a better analogy is the adoption of CQD as the distress signal for Morse operators (https://en.m.wikipedia.org/wiki/CQD). It's interesting, but the manner in which it was adopted has no story to it.
What if they simply said; no. Try again in a year. I wonder if SSH would be widespread today if that were the case
Request: Mon Jul 10 11:45:48 +0300 1995
Response: Date: Mon, 10 Jul 1995 15:35:33 -0700