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Comment by pierat | Hacker News Reader

Eh, not really. It's all a mistake how we *interpret* domain names.

From https://www.rfc-editor.org/rfc/rfc1034 3.6.1 , we see

----------------------

     For example, we might show the RRs carried in a message as:

     ISI.EDU.        MX      10 VENERA.ISI.EDU.
                     MX      10 VAXA.ISI.EDU.
     VENERA.ISI.EDU. A       128.9.0.32
                     A       10.1.0.52
     VAXA.ISI.EDU.   A       10.2.0.27
                     A       128.9.0.33

----------------------

Notice it's not ISI.EDU , but it's ISI.EDU. for an absolute fully-qualified domain name.

You can also notice weirdnesses here when you go to https://news.ycombinator.com. (copy and paste with period), like you're not logged in due to cookies not sharing.

But requiring absolute FQDN's would solve this https://financialstatement.zip -> https://financialstatement.zip. and remove the ambiguity.

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That's pedantic. We're not going to teach the world to include the root '.'

Its absolutely not pedantic, when you consider that TLDs of any language can be a thing. Its really nice to see a foreign language TLD, and know how to separate them appropriately.

The "." at the end also serves another level of defense. When you provide a URL without a . at the end, I can append .someotherdomain.com. and redirect traffic. And I've seen that in the wild before.

And the difference between "pedantic" and "technically correct" is how you get hacked. But feel free to throw insults. I know one of us is right, and it aint you.

And the difference between "technically correct" and "how things actually work in practice" is what keeps the world turning in the face of slight mismatches. See for example the URI/URL naming war. "URL" is a valid term for URI-like identifiers, even if they aren't locators.

No one (within a rounding error of 0%) will change how they enter, use, or program systems to work with, URLs to use the FQDN. The incompatibility nightmare it would cause would be insurmountable.

I mean, you might be technically correct. I say might because I have no expertise on the matter so I can’t really comment on it. But literally the entire world is using domain names without the final .

So I don’t think pointing out the technicality of how a domain name is supposed to be represented really helps in this context.

Apologies if the term 'pedantic' felt like an insult. It was not intended as one.

But you're not even technically correct when you claim "Eh, not really. It's all a mistake how we interpret domain names."...

This document clearly says that the dotless form is perfectly acceptable and even expected.

Take for example this snippet:

    Relative names are either taken relative to a well known origin, or to a
    list of domains used as a search list.  Relative names appear mostly at
    the user interface, where their interpretation varies from
    implementation to implementation, and in master files, where they are
    relative to a single origin domain name.  The most common interpretation
    uses the root "." as either the single origin or as one of the members
    of the search list, so a multi-label relative name is often one where
    the trailing dot has been omitted to save typing.

Which says that relative names are meant to be used in user interface (ie by humans) and the most common interpretation of a dotless name is to be in the global/root namespace.

So yes, the dotless notation comes down to own we interpret domain names. However that interpretation is not a mistake, it is expected.

Can you clarify what system would allow "DOT evil DOT com" to be appended to "good DOT com" but not "evil DOT com" to be appended to "good DOT com DOT"? I'm not familiar with the latter.

Not the original poster, but I think they talked about DNS search suffix lists. Often seen in company networks where host foo.internal.example.org might be reachable via foo because internal.example.org is the search suffix. That will not happen with `foo.`

Putting a period at the end seems like a very ineffective way to disambiguate a name. How do you do this at the end of a sentence?

Granny ain't gonna know that

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