SSH Mastermind
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I love technology. I love working with technology. So when I stumbled upon the origin story of our beloved SSH, I had to share it with you, my fellow tech geeks. I’m going to quote from the article, and share a link to it at the end of this page. Enjoy!

How SSH Port Became 22

The default SSH port is 22. It is not a coincidence. Tatu Ylonen wrote the initial version of SSH (Secure Shell) in the Spring of 1995. At this time, there were two widely used services in play; FTP and Telnet.

Tatu designed SSH to replace both telnet (port 23) and ftp (port 21). Port 22 was free, and was conveniently between the ports for telnet and ftp. Tatu figured having that port number might be one of those small things that would give him some aura of credibility. Yet, he wondered, “How could I get that port number? I had never allocated one before.” Thankfully he knew somebody who had allocated a port.

At the time, port allication was fairly simple. The internet was much smaller, and people were in the very early stages of the internet boom. The gatekeepers, the ones with authority, who could grant his request, was none other than the IANA (Internet Assigned Numbers Authority). At that time, it meant contacting two esteemed internet pioneers named Job Postel and Joyce K. Reynolds. Jon was the editor of a few minor protocol standards. You may have heard of them, they include: IP, ICMP, and TCP.

To Tatu, Jon felt outright scary, having authored all the main internet RFC’s. Just before announcing ssh 1.0 in July 1995, Tatu sent the following email to IANA:

From ylo Mon Jul 10 11:45:48 +0300 1995 From: Tatu Ylonen To: Internet Assigned Numbers Authority Subject: request for port number Organization: Helsinki University of Technology, Finland Dear Sir, I have written a program to securely log from one machine into another over an insecure network. It provides major improvements in security and functionality over existing telnet and rlogin protocols and implementations. In particular, it prevents IP, DNS and outing spoofing. My plan is to distribute the software freely on the Internet and to get it into as wide use as possible. I would like to get a registered privileged port number for the software. The number should preferably be in the range 1-255 so that it can be used in the WKS field in name servers. I'll enclose the draft RFC for the protocol below. The software has been in local use for several months, and is ready for publication except for the port number. If the port number assignment can be arranged in time, I'd like to publish the software already this week. I am currently using port number 22 in the beta test. It would be great if this number could be used (it is currently shown as Unassigned in the lists). The service name for the software is "ssh" (for Secure Shell). Yours sincerely, Tatu Ylonen ... followed by protocol specification for ssh-1.0
Tatu Ylonen
Software Engineer

The next day, Tatu received a response from Joyce with the response: “Tatu, We have assigned port number 22 to ssh, with you as the point of contact.”

Success!!!! And with that simple yet powerful response from Joyce, we now have a way to connect securely over insecure networks!

 If your like me, you use SSH for EVERYTHING. I use it to get a shell established to my linux servers. I use it to migrate data between devices. I’ve even went so far as to use SSH support as a basis for trying out a new piece of software, or replacing one with another product supporting SSH.

Well, if you want to read more, you can find the main article, along with other supplementary information here.

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