How SSH Port Became 22
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How SSH Port Became 22
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Re: How SSH Port Became 22
#2(2017)
Re: How SSH Port Became 22
#3Personally I find how/why FTP uses two ports, 20 and 21, to be more interesting:
So the first thing to know is the FTP is 'old', in that it predates TCP and originally ran on NCP:
> The original specification for the File Transfer Protocol was written by Abhay Bhushan and published as RFC 114 on 16 April 1971. Until 1980, FTP ran on NCP, the predecessor of TCP/IP.[2] The protocol was later replaced by a TCP/IP version, RFC 765 (June 1980) and RFC 959 (October 1985), the current specification.
* https://en.wikipedia.org/wiki/File_Transfer_Protocol
The second thing to know is that, unlike TCP or UDP, NCP was not duplex:
> NCP preceded the Transmission Control Protocol (TCP) as a transport layer protocol used during the early ARPANET. NCP was a simplex protocol that utilized two port addresses, establishing two connections, for two-way communications. An odd and an even port were reserved for each application layer application or protocol. The standardization of TCP and UDP reduced the need for the use of two simplex ports for each application down to one duplex port.[1]
* https://en.wikipedia.org/wiki/Network_Control_Program
So the original transport layer that FTP relied on necessitated two ports, and when the move to a newer transport layer occurred the use of two ports was carried over for simplicity's sake. And several decades later that design still exists.
Re: How SSH Port Became 22
#4TLDR; "Because I just asked for it."
Re: How SSH Port Became 22
#5Uh, it was the next available
near 23/telnet which it aimed to replace?
Re: How SSH Port Became 22
#6I’m more surprised that there is an ssh.com. And that it looks like it was put together with a bad corporate WordPress template.
Re: How SSH Port Became 22
#7Personally I find how/why FTP uses two ports, 20 and 21, to be more interesting: So the first thing to know is the FTP is 'old', in that it predates TCP and originally ran on NCP: > The original specification for the File Transfer Protocol was written by Abhay Bhushan and published as RFC 114 on 16 April 1971. Until 1980, FTP ran on NCP, the predecessor of TCP/IP.[2] The protocol was later replaced by a TCP/IP versio…
I've written a lot of TCP deep-packet inspection code, including parsing FTP control protocol. So I was surprised by this post by Robert Graham: https://blog.erratasec.com/2019/08/hacker-jeopardy-wrong-ans... - FTP control protocol follows the specification for Telnet.
Re: How SSH Port Became 22
#8With the benefit of hindsight, we know that ssh became extremely successful, so allocating it a nice port was a good choice.
Re: How SSH Port Became 22
#9I’m more surprised that there is an ssh.com. And that it looks like it was put together with a bad corporate WordPress template.
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Re: How SSH Port Became 22
#10I’m more surprised that there is an ssh.com. And that it looks like it was put together with a bad corporate WordPress template.
SSH is a publicly traded company since the dotcom era[1]. I think corporate wordpress feel is in line.
[1]https://en.m.wikipedia.org/wiki/SSH_Communications_Security