- From: Arun Manchanda <nalua@hotmail.com>
- Date: Thu, 12 Jun 1997 07:14:05 PDT
- To: nalua@rocketmail.com
- Cc: w3c-dist-auth@w3.org, urn-ietf@bunyip.com
>From w3c-dist-auth-request@w3.org Fri May 9 09:27:02 1997 >Received: by www19.w3.org (8.6.12/8.6.12) id MAA00043; Fri, 9 May 1997 12:10:42 -0400 >Resent-Date: Fri, 9 May 1997 12:10:42 -0400 >Resent-Message-Id: <199705091610.MAA00043@www19.w3.org> >Message-Id: <3.0.32.19970509100833.006f06f4@cic-mail.lanl.gov> >X-Sender: u114212@cic-mail.lanl.gov >X-Mailer: Windows Eudora Pro Version 3.0 (32) >Date: Fri, 09 May 1997 10:08:42 -0600 >To: Sukanta Ganguly <SGANGULY@novell.com> >From: "Ron Daniel, Jr." <rdaniel@lanl.gov> >Subject: Re: RFC 2141 on URN Syntax >Cc: w3c-dist-auth@w3.org, urn-ietf@bunyip.com >Mime-Version: 1.0 >Content-Type: text/plain; charset="us-ascii" >X-List-URL: http://www.w3.org/pub/WWW/Archives/Public/w3c-dist-auth/ >X-See-Also: http://www.ics.uci.edu/~ejw/authoring >Resent-From: w3c-dist-auth@w3.org >X-Mailing-List: <w3c-dist-auth@w3.org> archive/latest/776 >X-Loop: w3c-dist-auth@w3.org >Sender: w3c-dist-auth-request@w3.org >Resent-Sender: w3c-dist-auth-request@w3.org >Precedence: list > >At 08:54 AM 5/9/97 -0600, Sukanta Ganguly wrote: >>Hi, >> I wanted to mention some things about the rfc 2141 that I found confusing. > >You should bring these questions up on the URN-WG list, not the >Web DAV list. The URN list is urn-ietf@bunyip.com. I have added it >to the CC list on this reply. > >>The syntax for a URN is specified as >><URN> ::= "urn:" <NID> ":" <NSS> >>and NSS also has ":" as a characters recognized within the <others> rule. >>Based on this >> URN:foo:: -> Is this a valid URN ?? > >That will depend on the rules for the namespace foo. The URN syntax >is an attempt to be as liberal as possible so as to allow many >different namespaces to exist. The rules for particular namespaces >are intended to be much stricter. As an example, take a look at >the URN-WG's internet draft on using bibliographic identifiers as URNs. >Two of the namespaces in that document (ISBN and ISSN) disallow the use >of ':' and many other characters. The third (SICI) has much more >liberal rules because SICIs use lots of funny characters. > >>I feel that is ":" is used as a reserved terminator of a subsection of a >>rule then it should not be used in the recognized character sets for the >>other sub-sections of the rule. So I would imagine that ":" is not present >>as a recognizable character within the <other> rule of NSS subsection. > >The URN sytnax RFC takes a strong position on the first two occurances >of ':'. After that, it is up to particular namespaces how ':' is or is not >used. > >>It just adds an extra amount of parsing effort for the applications to have >>this feature in their parsing mechanisms. I don't say that it is impossible >>to have it, but as a application developer, it would be a much messy >>approach for me to write code that has this feature in it. I hope this not >>taken as a negative criticism. > >No, it is not taken as a negative criticism. However, one of the requirements >on URNs was the ability to grandfather legacy naming systems (such as SICIs). >If allowing ':' makes it easier to accomodate some naming schemes, then we >thought it would be worth some additional implementation difficulty. The >additional difficulty seems very small. The first two ':' characters are >required, so once one has stripped off the "urn:" prefix and the NID >field with its colon, no more special treatment of ':' is required for >a general URN parser. You will probably want to use the NID to lookup >special parsing rules for the namespace, but that is another story. > > >>I have a similar concern regarding the usage of "%" character within the >><NSS> subsection. This is what the rule resolution says >><NSS> ::= 1*<URN chars> >><URN chars> ::= <trans> | "%" <hex> <hex> >><trans> ::= <upper> | <lower> | <number> | <other> | <reserved> >><reserved> ::= '%" | "/" | "?" | "#" >> >>Here we observe that >> >> <NSS> ::= % could be a valid rule according to the rule definition. At >>the same time the system has another defination that says wheneever "%" is >>used two <hex> characters should be used. >> >> <NSS> ::=%%12 -> could also be a valid syntax for NSS. >> >>My suggestion here is to remove "%" from the <reserved> subsection of <NSS> >>rules. >> >>Please let me know if my thinking is along the lines of what the group has >>in mind or am I way out of wack. > >Single occurances of '%' are disallowed. '%' is supposed to ALWAYS mean >that the next two characters will be hex digits that are taken to >form an octet. > > >>I appreciate your acceptance of my >>participation in the group. >> >>Thank You >>Sukanta Ganguly >> >>>>> Jim Whitehead <ejw@ics.uci.edu> 05/06/97 12:07PM >>> >> >>Of potential interest to participants of this WG. >> >>- Jim >> >>>To: IETF-Announce: ; >>>Subject: RFC 2141 on URN Syntax >>>Cc: rfc-ed@isi.edu >>>Mime-Version: 1.0 >>>Date: Mon, 05 May 97 13:53:28 PDT >>>Sender:ietf-announce-request@ietf.org >>>From: RFC Editor <rfc-ed@isi.edu> >>> >>> >>>A new Request for Comments is now available in online RFC libraries. >>> >>> >>> RFC 2141: >>> >>> Title: URN Syntax >>> Author: R. Moats >>> Date: May 1997 >>> Mailbox: jayhawk@ds.internic.net >>> Pages: 8 >>> Characters: 14077 >>> Updates/Obsoletes: None >>> >>> URL: ftp://ds.internic.net/rfc/rfc2141.txt >>> >>> >>>Uniform Resource Names (URNs) are intended to serve as persistent, >>>location-independent, resource identifiers. This document sets >>>forward the canonical syntax for URNs. A discussion of both existing >>>legacy and new namespaces and requirements for URN presentation and >>>transmission are presented. Finally, there is a discussion of URN >>>equivalence and how to determine it. This document is the product of >>>the Uniform Resource Names Working Group of the IETF. >>> >>>This is now a Proposed Standard Protocol. >>> >>>This document specifies an Internet standards track protocol for the >>>Internet community, and requests discussion and suggestions for >>>improvements. Please refer to the current edition of the "Internet >>>Official Protocol Standards" (STD 1) for the standardization state and >>>status of this protocol. Distribution of this memo is unlimited. >>> >>>This announcement is sent to the IETF list and the RFC-DIST list. >>>Requests to be added to or deleted from the IETF distribution list >>>should be sent to IETF-REQUEST@CNRI.RESTON.VA.US. Requests to be >>>added to or deleted from the RFC-DIST distribution list should >>>be sent to RFC-DIST-REQUEST@ISI.EDU. >>> >>>Details on obtaining RFCs via FTP or EMAIL may be obtained by sending >>>an EMAIL message to rfc-info@ISI.EDU with the message body >>>help: ways_to_get_rfcs. For example: >>> >>> To: rfc-info@ISI.EDU >>> Subject: getting rfcs >>> >>> help: ways_to_get_rfcs >>> >>>Requests for special distribution should be addressed to either the >>>author of the RFC in question, or to admin@DS.INTERNIC.NET. Unless >>>specifically noted otherwise on the RFC itself, all RFCs are for >>>unlimited distribution. >>> >>>Submissions for Requests for Comments should be sent to >>>RFC-EDITOR@ISI.EDU. Please consult RFC 1543, Instructions to RFC >>>Authors, for further information. >>> >>> >>>Joyce K. Reynolds and Mary Kennedy >>>USC/Information Sciences Institute >>> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >Ron Daniel Jr. voice:+1 505 665 0597 >Advanced Computing Lab fax:+1 505 665 4939 >MS B287 email:rdaniel@lanl.gov >Los Alamos National Lab http://www.acl.lanl.gov/~rdaniel >Los Alamos, NM, USA, 87545 > > --------------------------------------------------------- Get Your *Web-Based* Free Email at http://www.hotmail.com ---------------------------------------------------------
Received on Thursday, 12 June 1997 10:15:05 UTC