Subject: Re: [Uri-review] Is TCP a URI scheme?

From: Ted Hardie <[email-masked]>
Date: Sat, 2 Feb 2019 02:17:45 +0900

I don't believe it has ever been registered, even provisionally, but you
can find example syntax in both IBM and TIBCO documentation of their
usage.  See, for example:

https://docs.tibco.com/pub/activespaces/2.1.6/doc/html/GUID-CAE482DF-C20D-46C4-AD2D-337535551423.html

and

https://www.ibm.com/developerworks/community/blogs/HermannSW/entry/dp_url_open_with_tcp_protocol_and_non_xml_response15?lang=en

You may have to find the documentation for the config format to get a truly
clear answer on the intended syntax here.

regards,

Ted Hardie

On Thu, Jan 31, 2019 at 7:21 PM Melvin Carvalho <[email-masked]>
wrote:

> Apologies if this is the wrong list.
>
> I was wondering if TCP is a URI scheme (formally or informally).  I dont
> see it here
>
> https://www.iana.org/assignments/uri-schemes/uri-schemes.xhtml
>
> Use case : I'm working with config in the lightning network and seeing
> config entries like this
>
> zmqpubrawblock=tcp://51.15.119..11:28332 <http://51.15.119.11:28332>
> zmqpubrawtx=tcp://51.15.119.11:28333
>
> If there's a better place to direct the question, Id be grateful to know.
> _______________________________________________
> Uri-review mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/uri-review
>

---

From: Eric Johnson <[email-masked]>
Date: Thu, 21 Feb 2019 16:49:43 -0800

> https://docs.tibco.com/pub/activespaces/2.1.6/doc/html/GUID-CAE482DF-C20D-46C4-AD2D-337535551423.html

Speaking somewhat on behalf of TIBCO, I'm not sure that the use of a string
that begins "tcp:" means that what is contained is necessarily a URL. I did
a small amount of very informal questioning of some of my fellow employees,
and didn't get the impression that the use of "tcp:" was anything other
than a signal for the type of thing that followed the prefix, and not
strictly speaking a "resource" locator.

Eric.

> You may have to find the documentation for the config format to get a
> truly clear answer on the intended syntax here.
>
> regards,
>
> Ted Hardie
>
>

---

From: Martin J. Dürst <[email-masked]>
Date: Fri, 22 Feb 2019 04:54:13 +0000

Hello Eric, others,

> strictly speaking a "resource" locator.

This overlaps quite a bit with what I'd have written as an answer to the 
original question if I had had some spare time when that comes up.

One of the core points of URIs is that they unify syntax at a very high 
level (the level of foo:). That makes them very useful for pointing at 
various things, from various places. The original place was the href 
attribute of the <a> element in HTML. There, the main schemes were 
http:, https:, ftp:, mailto:, and so on.

Other places where there was a need to point to something reused URIs, 
but once in a while, there was a need to point to something that didn't 
yet have an URI scheme. With the use of URIs expanding, such things got 
more and more diverse. That somebody somewhere wanted to point to a 
(potential) tcp connection, and would used tcp: for that, was just a 
matter of time.

For quite a while, registration of URI schemes was handled rather 
strictly. It's supposed to be easier today, but it's still some work, 
some discussion, and some wait. Also, the documents describing URIs are 
not necessarily an easy read for everyone, because they use general 
terms that can easily be misunderstood.

Also, please note that we are talking about URIs here, not URLs, so it's 
resource Resource Identifier, not Locator. And "resource" is really 
extremely general, even if for some schemes (e.g. mailto:), some care is 
needed when describing what exactly it stands for.

Looking at that page, it says "TCP Discovery URL Format". I'm not 
familiar with this "discovery" part, but it may have been better to use 
something like "tcp-disc:" or so as a prefix.

Regards,   Martin.

---

From: Graham Klyne <[email-masked]>
Date: Fri, 22 Feb 2019 11:19:27 +0000

I have a couple of comments prompted by this thread..

1. I propose that it is quite possible to use a string that conforms to URI 
syntax (explicitly or otherwise) without it being a URI.  So what makes it a 
URI?  Two touchstones that I apply are: (a) "what does it identify", and (b) 
"does it make sense to use it in a context where other URI schemes might equally 
be used" (e.g., as an href in an HTML document, or as a link relation type on an 
HTTP Link: header field).

2. Registration of *provisional* URI schemes is now first-come, first-served, 
without formal review, subject to satisfying some simple administrative 
requirements (cf. [1]).

    Permanent registration is a different matter, and does involve stricter 
requirements and formal review [2], which in turn involves some judgement by the 
reviewer about whether the requirements are satisfied.  As the current reviewer, 
I will typically look for indications of working group approval, similar from 
other recognized bodies like W3C, or "IETF review" (formerly "IETF consensus") 
[3] to inform that judgement.

[1] https://tools.ietf.org/html/rfc7595#section-4

[2] https://tools.ietf.org/html/rfc7595#section-3

[3] https://tools.ietf.org/html/rfc8126#section-4.8

#g
--

PS: since [4], I've personally come to further downplay the URI/URL distinction. 
I regard it as more to do with context of use than something inherent to the 
actual string form used, in that *any* identifier can be a locator given the 
right infrastructure (e.g,. DOIs), and any locator can potentially be used as an 
identifier.

[4] https://www.w3.org/TR/uri-clarification/

---

From: Martin J. Dürst <[email-masked]>
Date: Mon, 25 Feb 2019 05:56:31 +0000

Hello Graham, others,

On 2019/02/22 20:19, Graham Klyne wrote:
> 1. I propose that it is quite possible to use a string that conforms to 
> URI syntax (explicitly or otherwise) without it being a URI.  So what 
> makes it a URI?  Two touchstones that I apply are: (a) "what does it 
> identify", and (b) "does it make sense to use it in a context where 
> other URI schemes might equally be used" (e.g., as an href in an HTML 
> document, or as a link relation type on an HTTP Link: header field).

I agree. My main point was that URIs and URI schemes have been 
spreading, so href in an HTML document and link relation type in an HTTP 
Link: header field are only the top of the iceberg nowadays.

> 2. Registration of *provisional* URI schemes is now first-come, 
> first-served, without formal review, subject to satisfying some simple 
> administrative requirements (cf. [1]).
> 
>     Permanent registration is a different matter, and does involve 
> stricter requirements and formal review [2], which in turn involves some 
> judgement by the reviewer about whether the requirements are satisfied.  
> As the current reviewer, I will typically look for indications of 
> working group approval, similar from other recognized bodies like W3C, 
> or "IETF review" (formerly "IETF consensus") [3] to inform that judgement.
> 
> 
> PS: since [4], I've personally come to further downplay the URI/URL 
> distinction. I regard it as more to do with context of use than 
> something inherent to the actual string form used, in that *any* 
> identifier can be a locator given the right infrastructure (e.g,. DOIs), 
> and any locator can potentially be used as an identifier.
> 

For those who haven't been involved in that effort, and who haven't 
bothered to click on the link and check the data, it's from 2001, so 
really already quite a while ago. But it still very much (or even more 
so) applies at present.

Regards,   Martin.

>>   > On Fri, Feb 1, 2019 at 9:18 AM Ted Hardie <[email-masked]> wrote:
>>   >
>>   >> I don't believe it has ever been registered, even provisionally, 
>> but you
>>   >> can find example syntax in both IBM and TIBCO documentation of their
>>   >> usage.  See, for example:
>>   >>
>>   >>
>>   >>