[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Handle-info] Handle identifier and URN - what about the slash?
Hi Sam:
It might be helpful for us all to draw a stricter line here.
RFC 1630 is an early *informational* RFC on identifiers for WWW which
describes a unifying syntax.
RFC 3986 is the current (Jan. '05) *standards track* RFC which *specifies* a
generic syntax for (all) URIs.
I think that syntax discussions would better reference RFC 3986 which has a
long pedigree (via RFC 2396 and earlier docs) and represents the current
thinking and consensus on URI syntax and the URI raison d'etre.
Also URN should be seen for what it is within the contemporary view of URI,
nothing more but a particular URI namespace with its own purpose and its own
syntax. And btw, this does include restrictions on certain chars such as "/"
which are reserved.
Note also that since URIs use a subset of ASCII it is therefore not possible
generally to form *any* handle-based URI (whether native or URN namespaced)
without %-escaping. And since URN reserves the "/" char this MUST be
%-escaped in URN-based handle URIs. So, URN-based handle URIs MUST be
%-escaped, whereas native handle URIs MAY be %-escaped depending upon which
chars are used within the handle suffix.
And because of the char reservations in URN (RFC 2141), the write-up in the
DOI Handbook
http://www.doi.org/factsheets/DOIIdentifierSpecs.html
is somewhat misleading. "urn:doi:10.1000/1" is not a valid URI per RFC 2141.
Just my 2 cents. :)
Cheers,
Tony
On 7/12/06 13:11, "Sam X. Sun" <ssun@cnri.reston.va.us> wrote:7/12/06 13:11
> Hi Jakob,
>
> Here are my two cents to your questions:
>
> URN is generally considered a subset of URI and its syntax very much follows
> the URI syntax, as described in RFC1630. According to RFC1630, both '/' and
> '.' character are reserved for delimiting of substrings whose relationsip is
> hierarchical. The DOI-URN syntax you mentioned confirms to such practice. I
> don't see any problem with the way it uses '/' or '.' in its scheme
> definition.
>
> We also have some other applications that refers handles as URI/URL
> directly, under the "hdl:" URI scheme. But it's still unclear if we shall
> register the "hdl:" URI scheme, the "urn:hdl:" URN scheme, or both.
> Eventually, I think it's the application that will determine which way to
> go. Note that handle systems provides a name service that doesn't rely on
> the use of URI, URN, or URL. It provides an infrastructural service just
> like DNS, which operates independently from any web-application.
>
> Hope this helps.
>
> All the best,
> Sam
>
>
> ----- Original Message -----
> From: "Jakob Voss" <jakob.voss@gbv.de>
> To: <handle-info@cnri.reston.va.us>
> Cc: "Konstantin Rekk" <konstantin.rekk@gbv.de>
> Sent: Wednesday, December 06, 2006 7:59 AM
> Subject: [Handle-info] Handle identifier and URN - what about the slash?
>
>
>> Hi!
>>
>> We think about using handle but we also need to create URNs so we must
>> conform to RFC 2141 [1]. In RFC 2141 URN syntax is defined as
>>
>> <URN> ::= "urn:" <NID> ":" <NSS>
>>
>> <NSS> ::= 1*<URN chars>
>>
>> <URN chars> ::= <trans> | "%" <hex> <hex>
>>
>> <trans> ::= <upper> | <lower> | <number> | <other> | <reserved>
>>
>> <reserved> ::= '%" | "/" | "?" | "#"
>>
>> But it is also stated that reserved characters should not be used:
>>
>>> 2.3.2 The other reserved characters
>>>
>>> RFC 1630 reserves the characters "/", "?", and "#" for particular
>>> purposes. The URN-WG has not yet debated the applicability and
>>> precise semantics of those purposes as applied to URNs. Therefore,
>>> these characters are RESERVED for future developments. Namespace
>>> developers SHOULD NOT use these characters in unencoded form, but
>>> rather use the appropriate %-encoding for each character.
>>
>> However handle (RFC 3650 [2]) uses the slash ('/') to seperate Handle
>> Naming Authority and Handle Local Name:
>>
>> <Handle> ::= <Handle Naming Authority> "/" <Handle Local Name>
>>
>> For instance DOI as an application of Handle includes a slash in its
>> identifier but there is also an URN representation of DOI, although it
>> does not seem to be official [3], but known for years [4]. The syntax is
>>
>> <DOI-URN> ::= "urn:" "doi:" <Handle Naming Authority> "/" <Handle Local
>> Name>
>>
>>
>> My questions:
>> 1) Is it a problem to use such handle-based URNs with slash in it?
>> 2) Do you know of other uses of handle beside DOI that also use URN?
>>
>> Greetings,
>> Jakob
>>
>> References:
>> [1] http://www.ietf.org/rfc/rfc2141.txt
>> [2] http://www.handle.net/rfc/rfc3650.html
>> [3] http://www.doi.org/factsheets/DOIIdentifierSpecs.html
>> [4] http://www.dlib.org/dlib/may99/05paskin.html
>>
>>
>> _______________________________________________
>> Handle-Info mailing list
>> Handle-Info@cnri.reston.va.us
>> http://www.handle.net/mailman/listinfo/handle-info
>
>
> _______________________________________________
> Handle-Info mailing list
> Handle-Info@cnri.reston.va.us
> http://www.handle.net/mailman/listinfo/handle-info
********************************************************************************
DISCLAIMER: This e-mail is confidential and should not be used by anyone who is
not the original intended recipient. If you have received this e-mail in error
please inform the sender and delete it from your mailbox or any other storage
mechanism. Neither Macmillan Publishers Limited nor any of its agents accept
liability for any statements made which are clearly the sender's own and not
expressly made on behalf of Macmillan Publishers Limited or one of its agents.
Please note that neither Macmillan Publishers Limited nor any of its agents
accept any responsibility for viruses that may be contained in this e-mail or
its attachments and it is your responsibility to scan the e-mail and
attachments (if any). No contracts may be concluded on behalf of Macmillan
Publishers Limited or its agents by means of e-mail communication. Macmillan
Publishers Limited Registered in England and Wales with registered number 785998
Registered Office Brunel Road, Houndmills, Basingstoke RG21 6XS
********************************************************************************
_______________________________________________
Handle-Info mailing list
Handle-Info@cnri.reston.va.us
http://www.handle.net/mailman/listinfo/handle-info