Internet DRAFT - draft-finseth-isanlid
draft-finseth-isanlid
INTERNET-DRAFT C. Finseth
Firwood Consulting
28 March 2000
Referencing ISAN Identifiers with the Local Identifier (lid:) URI Scheme
draft-finseth-isanlid-00.txt
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet- Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
This document expires 28 September 2000.
Status of this Memo
This memo provides information for the Internet community. This memo
does not specify an Internet standard of any kind. Distribution of
this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2000). All Rights Reserved.
Abstract
This document specifies a method to use when referencing ISAN
identifiers with the local identifier ("lid:") URI scheme. By
specifying such referencing, broadcasts can avoid the overhead of
sending the same information multiple times and implementation
overhead can be reduced.
Finseth [Page 1]
INTERNET-DRAFT Referencing ISAN from lid: 28 March 2000
ISAN Identifiers
(This section is written using the author's best judgement of how the
system will eventually work. It will be updated as the in progress
work completes.)
These identifiers are the subject of a draft-ISO standard. Briefly,
ISAN identifiers are assigned to complete audio/visual works such as
television programs, movies, commercials, promotional spots, and so
forth. Each version of each work is assigned its own identifer.
ISAN Identifers are hexadecimal numbers written in the following
format:
AAAAAAAAAA-BBBB-CCCCC-D
where
- AAAAAAAAAA is a ten-digit hexadecimal number designating the work.
For television series, one of these identifiers is assigned for the
series as a whole.
- BBBB is a four-digit hexadecimal number designating the episode of
the series. For works that are not series, this value is always
"0000".
- CCCCC is a five-digit hexadecimal number designating the version.
Each materiela change in the work is assigned its own version number.
- D is a one-digit hexadecimal number that is a check digit.
The upper/lower case of the letters a-f is not significant.
Transmission
ISAN identifers can appear in a number of places in a broadcast. The
main locations will be in the electronic program guide and in the
information describing the program currently on the air. Each
transport (ATSC, DVB, etc.) will carry this information in a
different way, so consult the documentation on those systems for
specifics.
Mapping
Each receiver that implements the lid: URI scheme should take the
already-transmitted ISAN identifier and use it as a source of lid:
mapping information. The mapping is as follows.
Finseth [Page 2]
INTERNET-DRAFT Referencing ISAN from lid: 28 March 2000
For an ISAN identifier of the form:
AAAAAAAAAA-BBBB-CCCCC-D
act as if a lid: identifier of the form:
lid://isan.smpte.org/AAAAAAAAAA/BBBB/CCCCC/D
had been transmitted with the relevant mapping information. For
example, if the ISAN identifier had been encountered in the
electronic program guide, act as if the lid: had been transmitted
with mapping information targeting the relevant electronic program
guide slot.
Matching
With the above mapping in mind, lid: URI matching for references to
ISAN identifiers can proceed exactly the same as any other lid:
matching. There are, however, two special cases to consider.
First, a lid: URI of the form:
lid://isan.smpte.org/AAAAAAAAAA/BBBB
or
lid://isan.smpte.org/AAAAAAAAAA/BBBB/
should successfully match all versions of the material that the
receiver is aware of.
Second, a lid: URI of the form:
lid://isan.smpte.org/AAAAAAAAAA
or
lid://isan.smpte.org/AAAAAAAAAA/
should successfully match all versions of all episodes of the
material that the receiver is aware of. If the material is not a
series (e.g., is a move, commercial, etc.), this form returns the
same matches as the same as the match-all-versions form.
Security Considerations
This specification does not address security. It assumes that
security and access control are handled by policies and procedures
Finseth [Page 3]
INTERNET-DRAFT Referencing ISAN from lid: 28 March 2000
implemented in the systems themselves.
While this specification appears to provide a level of security by
virtue of the fact that the only resources accessible by an
application are those named in the broadcast stream, such is not the
case. Absent other policies and procedures, an ill-behaved
application can access resources by using device-specific mechanisms.
References
[1] "Uniform Resource Identifiers for Television Broadcasts", Mark
Vickers, Dan Zigmond, 02/21/2000. (10914bytes),
http://ietf.org/internet-drafts/draft-zigmond-tv-url-04.txt
[2] "The Local Identifier (lid:) URI Scheme", C. Finseth, Dean
Blackketter, Dan Zigmond, Gomer Thomas, Michael Dolan,
02/24/2000. (12122 bytes),
http://ietf.org/internet-drafts/draft-blackketter-lid-00.txt
[3] ten Kate, Warner; Thomas, Gomer; Finseth, Craig, "TV Broadcast URI
Schemes Requirements", 11 March 1999.
http://www.w3.org/TV/TVWeb/TVWeb-URI-Requirements-19990311
[4] "Guide to TV Broadcast URLs", C. Finseth, Gomer Thomas,
03/28/2000,
http://ietf.org/internet-drafts/draft-finseth-guide-01.txt
[RFC2396] Berners-Lee, T., Fielding, R., and L. Masinter,
"Uniform Resource Identifiers (URI): Generic Syntax", RFC
2396, August 1998.
Author's Address
Craig A. Finseth
Firwood Consulting
1343 Lafond
St Paul MN 55104
Phone: +1 651-644-4027
Email: craig@firwood.net
Full Copyright Statement
Copyright (C) The Internet Society (2000). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implmentation may be prepared, copied, published and
Finseth [Page 4]
INTERNET-DRAFT Referencing ISAN from lid: 28 March 2000
distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE."
This document expires 28 September 2000
Finseth [Page 5]
