How SSH port became 22 (2017)

https://www.ssh.com/academy/ssh/port#the-story-of-getting-ssh-port-22

by sysoleg • 2 years ago

408 169 2 years ago

ssh.com

justahuman74• 2 years ago

this WKS field in DNS that it refers to isn't something I've heard about

Why isn't it used?

mzs• 2 years ago

https://datatracker.ietf.org/doc/html/rfc1123#page-14

duskwuff• 2 years ago

The WKS record type was, at one point, a record listing all network services available on a host. It consisted of a bitmap where each bit represented a port number, counting from 0 (!), where a bit being set indicated that the host offered a service on that port. This scheme only worked for low port numbers; it also inappropriately conflated DNS names with hosts. (The latter was perhaps a reasonable assumption when WKS was created sometime in the '70s or '80s, but it certainly isn't anymore.)

The most definitive references to WKS are probably:

* RFC 1035 (1987), which defines the record format.

* RFC 1912 (1996), which noted that "[WKS records] serve no known useful function, except internally among LISP machines. Don't use them."

justsomehnguy2• 2 years ago

You can do a lot better now with SRV records.

usr1106• 2 years ago

In 1995 everybody sending email was trustworthy. Those were the days...

Edit: Except if their address was @aol.com. Eternal September started in 1993.

I_am_uncreative• 2 years ago

I have a shirt that says "The Internet is full: Go Away!"

tetris11• 2 years ago

I will pay you 5 cents to print 15 of those t-shirts, with my company logo on it and a QR code that points to an article about an internet standard and why my crypto startup is better than it. 10 cents, final offer.

bazil376• 2 years ago

“Can I have port 22?”

“Yes”

the early days of the internet are so fantastical to me I can’t stand it. Makes me sad to be too young to have witnessed it.

Dwedit• 2 years ago

The early days of the internet were dominated by InfoSeek Net Search, then later on Alta Vista was the search engine of choice. Then later on, Google appeared and everyone else couldn't compete.

lttlrck• 2 years ago

That's closer to an abridged history of "World Wide Web" search engines.

The internet was decades old when Infoseek appeared.

blahyawnblah• 2 years ago

Was it DEC than ran Alta Vista? They were involved in some search engine

demondemidi• 2 years ago

I was using Archie and gopher in the late 80s. Do you mean web search instead of internet search?

jjav• 2 years ago

The early days of the internet were dominated by InfoSeek Net Search

That's 20-some years after the early days of the Internet.

defrost• 2 years ago

I'd been using the internet for 14 years before InfoSeek Net Search appeared in 1994, this is honestly the first time I've heard of it.

I don't even consider myself an early user of the internet either, the people I learnt from had already been using it a good while.

djao• 2 years ago

There was also that time Jon Postel asked all the DNS root server operators to make his server the root, and they did. https://www.wired.com/2012/10/joe-postel/

grepfru_it2• 2 years ago

Ah yes back when NANOG was an irc channel and anyone could join and discuss their routing problems.

It was a simpler time for sure

tptacek9• 2 years ago

You don't really need permission to take a port; you can run your service on 80/tcp if you like.

jraph2• 2 years ago

Here it's different than this, the question is rather "Can it be recorded that port 22 is reserved for my tool so it becomes a worldwide convention?"

autoexec• 2 years ago

You can, but you'll have to deal with the consequences of violating conventions and the impact of that might matter very little or a whole lot depending on the situation. Running a random service over port 80 can be a good idea (lots of networks have that port open), but you'd better be willing to deal with the traffic from people/bots/crawlers looking for a webserver there. If you aren't careful you can break things on your own network or get yourself cut off from others. The rules and standards that exist are there to make everyone's lives easier and promote things working. Deviate from them at your own risk.

EnigmaFlare• 2 years ago

Even if you were old enough, you probably wouldn't have witnessed it because it was only being worked on by a small number of people. There must be amazing future things which are in their early days right now but you and me aren't involved with them and nobody knows for sure what they even are until they explode.

I'm old enough to remember the early days of Bitcoin and how nobody I talked to about it had ever heard of it and was either dismissive ("That would be easy to hack" / "that can't work") or just treated it like a random chit-chat that didn't matter.

DonHopkins4• 2 years ago

Wow that's a lot less negotiation than is required to tell a TCP joke! ;)

  Hello, would you like to hear a TCP joke?

  Yes, I'd like to hear a TCP joke.

  OK, I'll tell you a TCP joke.

  OK, I'll hear a TCP joke.

  Are you ready to hear a TCP joke?

  Yes, I am ready to hear a TCP joke.

  OK, I'm about to send the TCP joke. 
  It will last 10 seconds, 
  it has two characters, 
  it does not have a setting, 
  and it ends with punchline.

  OK, I'm ready to hear the TCP joke 
  that will last 10 seconds, 
  has two characters, 
  does not have a setting, 
  and will end with a punchline.

  I'm sorry, your connection has timed out...

  ...Hello, would you like to hear a TCP joke?

mxuribe2• 2 years ago

OMG, this is brilliant! How have i never heard this one before!?! Thanks for sharing! :-D

dang2• 2 years ago

How SSH got port number 22 - https://news.ycombinator.com/item?id=33363795 - Oct 2022 (2 comments)

How SSH Port Became 22 - https://news.ycombinator.com/item?id=21350246 - Oct 2019 (81 comments)

How SSH port became 22 - https://news.ycombinator.com/item?id=17552100 - July 2018 (95 comments)

How SSH got port number 22 - https://news.ycombinator.com/item?id=14178091 - April 2017 (207 comments)

ChrisArchitect• 2 years ago

(2017)

Was this article updated recently in some way? Not sure why it's mentioned at top of page, maybe just appended for posterity.

HN discussion then: https://news.ycombinator.com/item?id=14178091

dang2• 2 years ago

Ah thanks! I've updated the list above.

danielvaughn• 2 years ago

I’ve always wanted to see something like a common port dictionary or encyclopedia. Just a big list of all the ports, each with their common usage and the history behind it.

presentmonkey• 2 years ago

There's this wiki page that's pretty cool https://en.m.wikipedia.org/wiki/List_of_TCP_and_UDP_port_num...

skissane2• 2 years ago

Wikipedia's list is better than the official one because it explains what some of those protocols actually are – especially the early ones which don't have any RFC specified in IANA's registry.

Although, in several cases, there is an RFC, even though IANA's registry doesn't record it. For example, port 1 (tcpmux / TCP Port Service Multiplexer) uses a protocol defined by RFC1078, as Wikipedia's article on it helpfully explains – https://en.wikipedia.org/wiki/TCP_Port_Service_Multiplexer – but IANA's registry doesn't mention that.

Or similarly, port 5 is listed as rje / Remote Job Entry in the registry, but Wikipedia helpfully notes that it is the protocol defined by RFC407 (and maybe RFC725 is a newer version of it?). I doubt that ARPANET RJE protocol (whose syntax resembles FTP, SMTP, etc) ever saw any great amount of implementation; I believe historically the most popular RJE protocols were IBM's (2780/3780 and later Network Job Entry / NJE which was used in RSCS, most notably on BITNET) – but those protocols don't have an assigned port number, since they don't natively run on top of TCP/IP.

There are however some historical mysteries in this IANA registry for which even Wikipedia does not know the answer: the first of many is what ports 2 and 3, "compressnet", were used for. (Edit: What Wikipedia doesn't know, HN does: https://news.ycombinator.com/item?id=37016159

hiAndrewQuinn• 2 years ago

Seconded. I made some Anki cards out of the table of the "Well-known ports" table and it has proven surprisingly helpful fingertip knowledge for my kind of work (Linux systems and small scale networks in odd places).

extraduder_ire• 2 years ago

Notably: port 666 - "Doom, the first online first-person shooter"

I'd like to see that email to IANA.

XorNot• 2 years ago

I mean if we wait long enough everything will be on port 443...

skissane2• 2 years ago

Questions from the distant future: "Why is there this hardcoded 16-bit field in the UDP header which is always 443? Why do we have an IPv6 header which is always followed by a UDP header which is always followed by a QUIC header? Why not just merge the three headers into one?"

And then RFC99999 defines a "new protocol" in which there is just a single header, which happens to have the same byte layout as IPv6+UDP+QUIC, with a bunch of fields like "reserved_01BB" which "always contains the bytes 0x01BB due to historical backward compatibility reasons"

dabber• 2 years ago

You can start with the IANA list [0]. You won't find posts like this listed but it should be a good place to start regardless.

[0] https://www.iana.org/assignments/service-names-port-numbers/...

adamzegelin• 2 years ago

On Linux, /etc/services often contains a list of at least protocol names and numbers.

ttyprintk• 2 years ago

Nmap ships with an nmap-services file, which is a lot like /etc/services. However, you might find it interesting because it lists common worm backdoor ports rather than some obscure license server.

Nition• 2 years ago

One fun list is in the default NetComm router software which still has a huge list of pre-saved port forwarding info for multiplayer PC Games that hasn't been updated since around 2001. That's quite a fun nostalgic list to browse.[1]

[1] Here's A-D: https://i.imgur.com/tCn2FBB.png

aussieguy1234• 2 years ago

I always figured FTP is port 21, SFTP/SSH is port 22

IronWolve• 2 years ago

They seem to always leave off port 20 is also ftp.

grepfru_it2• 2 years ago

It’s just a data channel. This changed with nat and the introduction of the PASV command which allowed the client to set a non-well known port for the data channel

broodbucket• 2 years ago

That's exactly what TFA says?

joak• 2 years ago

Announced officially to the mythical cypherpunks@toad.com mailing list...

Fighting to legalize cryptography on the internet. PGP was banned. Sending encrypted emails was illegal...

Cypherpunks won. Thanks to them.

IAmNotACellist• 2 years ago

Conspiracy-minded theory: only once the government successfully arranged for a process (behind closed doors) to subvert or capture any US-based cryptography efforts or communications.

tptacek9• 2 years ago

Where were you that PGP was banned, or encrypting emails was illegal?

mratsim10• 2 years ago

Cryptography was considered a war weapon and only allowed for military use.

The United States had to be brought to court to finally allow cryptography: https://en.m.wikipedia.org/wiki/Bernstein_v._United_States

Years before, the government had placed encryption, a method for scrambling messages so they can only be understood by their intended recipients, on the United States Munitions List, alongside bombs and flamethrowers, as a weapon to be regulated for national security purposes. Companies and individuals exporting items on the munitions list, including software with encryption capabilities, had to obtain prior State Department approval. — Electronic Frontier Foundation: EFF's History

Before that, export rules could be "worked around" by printing cryptography in books.

atoav• 2 years ago

You are probably from the US and not aware how things looked outside of it? https://en.m.wikipedia.org/wiki/Crypto_Wars

michaelt• 2 years ago

PGP was not exactly banned but if you were in Europe when ITAR restricted its export, and you were trying to download from strait-laced corporate types like AOL, they wouldn't let you.

And even if a determined person could get around the blocks, they severely limited the network effects; office workers on their employers' PCs weren't going to be getting encryption software from IRC bots to bypass arms export laws.

Some time towards the late 90s PGP became much more easily available.

jeroenhd• 2 years ago

Encryption was (and in some countries, still legally is) considered dual use technology. You needed to go through paperwork and licensing to export cryptography across the border. Symmetric keys longer than 64 bits were considered too strong.

This led to all kinds of stupidity. Internet Explorer shipped with nerfed TLS capabilities, limiting key sizes to 40 bits or 56 bits depending on the version.

When the encryption laws changed in 2000, Microsoft allowed users to download an update to improve SSL encryption: https://learn.microsoft.com/en-us/previous-versions/tn-archi...

You could legally encrypt emails, of course, as long as you kept the key sizes small and didn't export the encryption software to another country.

If you sell and export encryption products from the USA (and a bunch of other countries, see the Wassenaar Accords) to certain places (including China and Russia), you're still obligated to register your product if you use modern key sizes. I'm not sure if governments still care now that OpenSSL and PGP are freely available to anyone, but if your proprietary email encryption program is found on North Korean computers, your government may ask you some uncomfortable questions.

sliken• 2 years ago

As discussed on thread, not banned, but posting it somewhere could get you in significant trouble. In fact, Phil Zimmermann got in quite a bit of trouble for his contribution towards the world getting a hold of PGP, which was considered a export restricted munition. I believe there was at least one court case, harassment, tax audit, and hassle at the border. My memory is a big vague, but you get the idea.

I was at codecon, forget if Zimmerman was there, or just quoted. His story was recounted, then someone else who attended codecon and mentioned releasing ITAR restricted crypto. They were part of a leak of the RC4 source code. A copy was sent to a well known member of sci.crypt, saying along the lines of "I think you can post this anonymously", if you agree to this please post a "Looking for Joe Random" post on sci.crypt. The source code was posted and there was no lawsuit, no tax audit, and no hassling by the government.

astrashe2• 2 years ago

I was on the Cypherpunks list, mostly as a lurker. The technical discussions were amazing. I was really into it at the time, but now I find some of the political ideas to be embarrassing.

Other people had a lot to do with the spread of strong crypto as well. Many people realized that encryption was necessary if we wanted to do business online. Matt Blaze (who was on the Cypherpunks list, but never said anything crazy), helped blow up the government's compromise solution, mandatory key escrow, by demonstrating flaws in their Clipper chip technology. The MIT Press published PGP's source code in book form, using an OCR font, because books couldn't be blocked as munitions. I think Hal Abelson, who wasn't on the list, was the person behind that.

The basic political idea behind the list was that you could effect change by writing code. Instead of going to the government, with your cap in your hand, and saying, Please, sir, can we have strong encryption?, you write code and give it away, thus making the law impossible to enforce. This sounds really cool when you're young, especially if you write code, but it's an anti-democratic idea.

The political positions of some of the leaders was kind of an extreme, anarchist spin on libertarianism. Bitcoin is a currency designed to solve a specific problem -- it's kind of the ultimate solution to the old goldbug fear that governments will print money and dilute the currency. That's impossible under Bitcoin.

The original crypto currency the Cypherpunks were really into was David Chaum's Digicash, which was designed to solve a completely different problem, the same one Monero is aimed at today. It was supposed to be untraceable. Instead of asking governments to lower taxes, the idea was that programmers could create a way to transfer funds anonymously. In theory, taxes would become impossible to collect, and national borders would collapse.

Eventually this led to things like discussions of anonymous murder contracts. There was a proposed protocol that was supposed to allow you to put out a hit on someone with complete safety. You could pay the killer anonymously with digital currency. I think the payment would go into some sort of escrow, so the killer would know they'd get paid. I don't remember how the system was able to know that the hit had taken place.

Those murder contracts were one of the things that made me pull back from the list. But it really was terrific to read, even though I think it would be a mistake to lionize it too much. Arguably, they were struggling to make the whole world run on 8chan's rules.

Hendrikto• 2 years ago

This sounds really cool when you're young, especially if you write code, but it's an anti-democratic idea.

Is it? Code was deemed free speech, after all. So suppressing it would be anti-democratic, not spreading it.

j16sdiz• 2 years ago

I wonder if IANA still assign numbers? Can I have them assign ports for, say, redis?

sgjohnson• 2 years ago

Yes, they do. Their mission hasn’t changed since IANAs inception.

But getting a port assignment these days is going to be virtually impossible. It’s probably not going to happen without at least a Proposed Standard RFC.

https://www.iana.org/assignments/service-names-port-numbers/...

There’s not a single RFC published that concerns redis. It’s not going to happen.

ivlad• 2 years ago

I got a port assigned a few years ago.

I needed to write a justification why the organisation I represented needs a port number (a custom binary protocol), a formal confirmation that protocol has versioning built-in (so we will not request for a new port number for the next version of the protocol), a confirmation that we have a running code implementing the protocol (if I recall correctly, link to documentation was sufficient), and the reasons why we cannot use any of the existing protocols.

It’s not impossible and I think it’s totally doable for redis unless the port is already reserved for something else.

dmurray• 2 years ago

Probably for the best.

If there was a moderately complicated bureaucratic process to be assured of getting one, it wouldn't be Redis or the next SSH that got assigned ports. It would be Oracle or HP or someone else incapable of pretending to be a good Internet citizen, who filled in 10,000 of the forms promising that they have 10,000 totally necessary well known enterprise services.

chupasaurus• 2 years ago

Someone should steal 666 TCP/UDP, no RFC and contact email is of a person who leaved id in 1996.

elzbardico• 2 years ago

They could if redis went the way of proposing a RFC for their protocol. But I don't think it would be a good idea. But, if instead someone came up with a RFC proposing a standard protocol for communications with generic key-value stores like redis, it would make a lot more sense.

teddyh5• 2 years ago

You shouldn’t need a hardcoded port number for a newly designed protocol. Register a service name instead, and use SRV or SVCB records in the DNS (and/or ZeroConf).

You’ll notice that on the official IANA list of port numbers and service names, there is a separate section, after the numbered ports, listing only service names¹. Just apply for one of those.

1. At the time of writing, starting on page 135 of the HTML version: <https://www.iana.org/assignments/service-names-port-numbers/...>

a-dub• 2 years ago

reminds me of the days when s/keys over telnet were cool.

there should be a vh1 where are they now special for assigned ports in /etc/services that shipped with early slackware.

SeanLuke• 2 years ago

The headline of the article does not match the posting, which breaks a rule I believe. Could we at least correct the posting's grammar? To "How SSH became Port 22".

acer4666• 2 years ago

"The -p <port> option can be used to specify the port number to connect to when using the ssh command on Linux. The -P <port> (note: capital P) option can be used with SFTP and scp."

The most annoying thing about SSH/scp!

dijit• 2 years ago

I always just use -o port=<xx> for this reason.

jbaber• 2 years ago

Wait, lower case 'o' works?

lnxg33k1• 2 years ago

I use rsync with -e 'ssh -p PORT', so that I can also have the ability to resume just in case :D, interesting how everyone has a different solution ^^, let's see how many ways of doing the same thing can we collect in this thread

hsbauauvhabzb3• 2 years ago

Use ~/.ssh/config to add per host or wildcard values for port :)

bombcar• 2 years ago

This right here is the next big trick behind using CTRL+R to find the last ssh command.

DiggyJohnson2• 2 years ago

~/.ssh/config is one of the simplest, most useful features I use on a daily basis. It would be easy to accomplish much of it's behavior even if it didn't exist (bash script for each account@host), but it wouldn't be as elegant.

The config-aware shell completion is especially cool.

zamadatix2• 2 years ago

Great if you only ever ssh from your primary box/profiles, an amplifier of the problem (due to entering the commands less often) otherwise!

tracker1• 2 years ago

I use this for aliasing as much as for Port assignment.

blensor• 2 years ago

What's even more annoying is that -P for scp has to be put before the target while -p for the ssh client I am using can be put after the target.

So when you write your scp command and then realize you forgot to put in the port you have to go back and put it before the target.

deaddodo4• 2 years ago

The most annoying thing about SCP is args ordering, I would have preferred a single direction arg for transfer details, if it meant we didn't have to worry about positional args.

Then again, I'm speaking as someone that came into the scene well after development, so that could just be annoyance via naivete.

rnts08• 2 years ago

Even more fun when you are doing ssh, scp and throw in some random nmap in there as well, where -P and -p are both used.

mpcjanssen• 2 years ago

Add the lowercase -r for recursive scp and you have two screens with man pages open.

atribecalledqst• 2 years ago

This tripped me up hardcore at work recently, because I was trying to SSH into a VM using a non-standard port, but the port-forwarding went from the non-standard port into the usual 22 on the VM. So when I got "Connection Refused" on port 22, I thought that meant the connection was getting through the NAT layer but then failing at the VM for some reason.

NOPE I'd just specified the option wrong!

codegeek• 2 years ago

Agreed :). I always have to google which case applies where as I use ssh and scp heavily.

donalhunt• 2 years ago

Had a very similar experience when I requested a Private Enterprise Number (PEN) in the early 00s.

I was doing some experimentation with LDAP, mailman and identity based encryption and needed some OIDs to support my undergraduate project work.

Private Enterprise Numbers are identifiers that can be used in SNMP configurations, in LDAP configurations, and wherever the use of an ASN.1 object identifier (OID) is appropriate.

So I went about signing up my university for a PEN. It helped that I also worked for the IT Services team at the time but I distinctly remember the request being done by email with the response more of less being "here's your number". :)

To my knowledge, I believe I'm the only person who has made use of the PEN assigned to the university.

mjlee• 2 years ago

Why 22 was available is also interesting. Network Control Protocol was the precursor to TCP and used different ports for inbound and outbound traffic, typically even for outbound and odd for inbound.

If you look in /etc/services you'll notice that all the older protocols listen on odd numbered ports.

Some of this still survives today. In active mode FTP servers listen on 21, ACK the inbound request and then connect to the client from 20.

macintux2• 2 years ago

I do not miss the days of trying to figure out which FTP mode would work through a given firewall configuration.

imaginator• 2 years ago

This is a good example of make it easy for others to say yes.

teddyh5• 2 years ago

I designed SSH to replace both telnet (port 23) and ftp (port 21).

As I have written here previously¹, that’s actually a bit of revisionist history, or at least a significant omission. Speaking as someone who was actually using Unix systems when this happened, the "ssh" command was replacing the rsh command, and also still ships an "slogin" command, replacing rsh’s companion command, "rlogin" (and "scp" replaced "rcp"). Where I was, nobody was even using telnet or FTP internally; everybody was using rsh, rlogin and rcp! This also better explains the naming; going from "rsh" to "ssh" is easier.

If someone had wanted to make telnet encrypted, they would just have had to implement the standard telnet protocol and add another option in the protocol; it has a bunch already, and even one for encryption, IIRC.

1. <https://news.ycombinator.com/item?id=14178333>

throw0101c• 2 years ago

If someone had wanted to make telnet encrypted, they would just have had to implement the standard telnet protocol and add another option in the protocol […]

    This document describes a the telnet encryption option as a generic
    method of providing data confidentiality services for the telnet data
    stream.  While this document summarizes currently utilized encryption
    types and codes, it does not define a specific encryption algorithm.
    Separate documents are to be published defining implementations of
    this option for each encryption algorithm.

* https://datatracker.ietf.org/doc/html/rfc2946

teddyh5• 2 years ago

So I did recall correctly, then.

kloch• 2 years ago

Speaking as someone who was actually using Unix systems when this happened, the "ssh" command was replacing the rsh command,

A different data point: I was also a Unix sysadmin at the time (thought just out of school) and for me ssh replaced telnet and ftp. I never used rsh, rlogin, and rcp except when testing exploits.

teddyh5• 2 years ago

In my experience, telnet and FTP were used when accessing external resources; when wandering around the local menagerie of machinery, rsh, rlogin and rcp were predominant.

linsomniac• 2 years ago

Ditto, I had been doing sysadmin as my job for a few years in 1995 and as a component of my job or as a hobby for ~5 years before that. I was decidedly a telnet/ftp guy before ssh, and dabbled a little with "ssltelnet". I mostly avoided rsh and family because I didn't love the security model.

SSH was a fantastic improvement at the time, though the whole licensing model interfered with my use for the first several years.

Accujack• 2 years ago

My experience as well.

Much depends on whether your systems were running BSD-style RPC services.

NelsonMinar• 2 years ago

Oh, rsh, your security model was so cute. It runs on port 513. (There is also rexec, port 512, and rcp on port 514. rlogin runs on port 513 along with rsh.)

mistrial9• 2 years ago

Berkeley compute facilities used $rsh and $rlogin .. not clear on the file transfer from the outside. Dial-up modem from a residential phone line in those days, this was before 9600 baud became common for individuals.

ftp on the other hand was more like finger or similar.. going to some external site that was public, or had a login to distribute files.

midtake• 2 years ago

I think it's a bit unfair to call it revisionist. It's a direct claim by the author of ssh, and out of all the ports numbered 1-255, telnet (23) does come closest in function to ssh. I believe the article is more about how lucky the author got to nestle a port between two other protocols that ssh superseded, rather than the thinking behind the naming of the ssh family of protocols.

LeFantome• 2 years ago

He included the letter he wrote to IANA so, unless you are calling fraud, it is actual history rather than revisionist history.

In that letter he says: “It provides major improvements in security and functionality over existing telnet and rlogin protocols”.

So, while you are correct about rsh, it seems totally fair ( and likely just correct ) for him to say he chose port 22 for its proximity to telnet. Also, since SSH includes SFTP, what he says about FTP checks out as well.

The story is about “why 22” and telnet answers that question better than rsh does. I guess if the question was “why ssh”, the details you added would matter more.

falqun• 2 years ago

Without having any specific information on the matter at hand: revisionist history does not need fabricated facts. Its very possible to revision history by omitting crucial parts. Hence the letters might be genuine and someone revisions history by leaving out other relevant information.

pantulis• 2 years ago

We have assigned port number 22 to ssh, with you as the point of contact. Joyce

Those were the early days when you could be designated as the point of a contact for a TCP port connection number and expect not to be swamped by emails!

notbeuller• 2 years ago

I used to have a registered port (in the 3000s) - didn’t get a lot of spam, but once I got a very angry phone call (!!!) from someone that tracked me down because their firewall blocked an incoming request in that port. They did their own research and decided it was my fault.

kshay• 2 years ago

I like how he didn’t explicitly request 22. It was more like “anything 1-255 would be great... oh, by the way, I happen to be using 22...”

hk__22• 2 years ago

He did request it:

It would be great if this number could be used

hk__22• 2 years ago

    From: Tatu Ylonen <ylo@cs.hut.fi>
    To: Internet Assigned Numbers Authority <iana@isi.edu>
    Subject: request for port number
    Organization: Helsinki University of Technology, Finland

Was "Organization" a common email header at the time? This is the first time I see it.

teddyh5• 2 years ago

Many e-mail client still has a field for it in its account settings.

dannyobrien• 2 years ago

Yes!

FredPret• 2 years ago

SSH is the most fantastic piece of black magic. So many incredible things are easy and secure.

Port forwarding

Reverse port forwarding

Rsync

So much more. And it's free. What a privilege to be alive today - I remember when all this was just a dream.

emmelaich• 2 years ago

ssh also used to use source port 22. At least a popular implementation of it did. A bit of websearching didn't find it; anyone else remember this?

zamadatix2• 2 years ago

Wouldn't that have meant you couldn't ssh out of a machine running an ssh server since the port was already bound to another process?

How SSH port became 22 (2017)

Related Stories