Skip to main content

Media Type Registrations for Downloadable Sounds for Musical Instrument Digital Interface (MIDI)
draft-westerlund-mime-dls-01

The information below is for an old version of the document that is already published as an RFC.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 4613.
Authors Per Frojdh , Magnus Westerlund , Ulf A. Lindgren
Last updated 2015-10-14 (Latest revision 2006-02-14)
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status Informational
Formats
Stream WG state (None)
Document shepherd (None)
IESG IESG state Became RFC 4613 (Informational)
Action Holders
(None)
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD Ted Hardie
Send notices to (None)
draft-westerlund-mime-dls-01
Network Working Group                                          P. Frojdh
INTERNET-DRAFT                                               U. Lindgren
draft-westerlund-mime-dls-01                               M. Westerlund
Expires: August 2006                                            Ericsson
                                                       February 10, 2006

         Media Type Registrations for Downloadable Sounds for MIDI

Status of this memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

   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/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html

   This document is an individual submission to the IETF. Comments
   should be directed to the author.

Abstract

   This document serves to register a media type for Downloadable
   Sounds.

Frojdh, Lindgren and Westerlund                                 [Page 1]
INTERNET-DRAFT        draft-westerlund-mime-dls-01     February 10, 2006

TABLE OF CONTENTS

   1. Conventions Used.................................................3
   2. Introduction.....................................................3
   3. Security Considerations..........................................3
   4. IANA Considerations..............................................4
   4.1. Downloadable Sound.............................................4
   5. RFC Editor Considerations........................................6
   6. Authors' Addresses...............................................6
   7. References.......................................................6
   7.1. Normative......................................................6
   7.2. Informative....................................................7
   8. IPR Notice.......................................................7
   9. Copyright Notice.................................................7

Frojdh, Lindgren and Westerlund                                 [Page 2]
INTERNET-DRAFT        draft-westerlund-mime-dls-01     February 10, 2006

1. Introduction

   The present document seeks to register a media type for
   Downloadable Sounds (DLS). The DLS format is used to define
   instruments for widely used wavetable synthesizers associated with
   the standards [DLS1, DLS2, MDLS]. DLS, and their associated
   standards are maintained and defined by two organizations, the MIDI
   Manufacturers Association (MMA) and the Association of the Musical
   Electronics Industry (AMEI).

   The media type defined here is needed to correctly identify DLS
   files when they are served over HTTP, included in multi-part
   documents, or used in other places where media types are used.

2. Security Considerations

   The DLS format may contain audio, displayable text data, and
   modeling parameters (a.k.a. articulation parameters). In addition,
   the DLS format contains a so-called conditional chunk which is
   'active' in the sense that it affects the execution of a DLS file
   parser. However, the DLS format does not currently define any
   scripting mechanism.

   Clearly it is possible to author malicious files which, for
   example, contain large amounts of data always blocked by a
   conditional statement, i.e. no synthesizer loads the instruments.

   However, for DLS, clients can and usually do protect themselves
   against these kinds of attacks. For DLS content containing
   conditional chunks it is stressed that the chunk in question is
   optional, that is to say a parser does not have to execute the
   chunk. However, if a parser evaluates a conditional chunk, it is
   still possible to parse its content and draw a conclusion whether
   or not it is usable for a particular synthesizer engine.

   It should be noted that selected metadata fields may include
   information partly intended to protect the media against
   unauthorized use or distribution. In this case the intention is
   that alteration or removal of the data in the field would be
   treated as an offence under national agreements based on World
   Intellection Property Organization (WIPO) treaties.

   DLS have an extensible structure, making it theoretically possible
   to define metadata fields or media formats in the future which
   could be used to induce particular actions of the recipient, and
   thus present additional security risks. However, this type of
   capability is currently not supported in the referenced
   specifications.

Frojdh, Lindgren and Westerlund                                 [Page 3]
INTERNET-DRAFT        draft-westerlund-mime-dls-01     February 10, 2006

   There is no current provision in the DLS standard for encryption,
   signing, or authentication within the file formats.

3. IANA Considerations

   The present document requests that IANA registers the media type
   audio/dls as specified in Section 3.1. The registration uses the
   template present in [RFC4288].

3.1. Media Type for Downloadable Sounds

   Type name:                         audio

   Subtype name:                      dls

   Required parameters:               none

   Optional parameters:               'dls-type'
                                      A comma-separated list of the
                                      dls types (one or more) that the
                                      file content conforms to. The
                                      following values are specified:
                                      0, 1, and 2 signify Downloadable
                                      Sounds Level 1.1b content,
                                      Downloadable Sounds Level 2.1
                                      content, and Mobile Downloadable
                                      Sound content, respectively. All
                                      types that the content conforms
                                      to should be indicated. Further
                                      values (integers) may be
                                      specified in the future, and any
                                      unknown values shall be ignored.
                                      If the parameter is not
                                      specified, it corresponds to a
                                      value equal to 0, i.e. the
                                      content conforms to Downloadable
                                      Sound level 1.1b.

   Encoding considerations:           DLS files are binary and should
                                      be transmitted in a suitable
                                      encoding without CR/LF
                                      conversion, 7-bit stripping
                                      etc.; base64 [RFC3548] is a
                                      suitable encoding.

   Security considerations:           see the security considerations
                                      in section 3 of RFC XXXX.

Frojdh, Lindgren and Westerlund                                 [Page 4]
INTERNET-DRAFT        draft-westerlund-mime-dls-01     February 10, 2006

   Interoperability considerations:   This media type is for the
                                      consumption by a MIDI player
                                      capable of utilizing
                                      downloadable sounds for its
                                      synthesizers. A general purpose
                                      audio player will not be capable
                                      of utilizing the audio within
                                      the format without explicit
                                      support of the format.

   Published specification:           Downloadable Sounds Level 1.1b
                                      [DLS1], Downloadable Sounds
                                      Level 2.1 [DLS2], and Mobile
                                      Downloadable Sounds [MDLS]. MMA
                                      specifications can be ordered
                                      from the MMA web site,
                                      www.midi.org.

   Applications which use this media type: Multi-media

   Additional information:

      Magic number(s):                The ninth to twelfth bytes of
                                      the file must equal (in
                                      hexadecimal notation) 44, 4c,
                                      53, and 20, respectively.
      File extension(s):              .dls is declared at
                                      http://www.nist.gov/nics

   Person & email address to contact for further information:
                                      Ulf A. Lindgren,
                                      ulf.a.lindgren@ericsson.com

   Intended usage:                    COMMON

   Restrictions on usage:             None

   Author:                            Per Frojdh
                                      Ulf A. Lindgren
                                      Magnus Westerlund

   Change controller:                 MIDI Manufacturers Association
                                      http://www.midi.org
                                      info@midi.org

Frojdh, Lindgren and Westerlund                                 [Page 5]
INTERNET-DRAFT        draft-westerlund-mime-dls-01     February 10, 2006

4. RFC Editor Considerations

   The references to RFC XXXX in the media type registration need to
   be replaced with the actual RFC number when it is issued.

   Please remove this section before publication as RFC.

Authors' Addresses

   Per Frojdh
   Ericsson AB
   Ericsson Research
   SE-164 80 Stockholm
   Sweden
   electronic mail: per.frojdh@ericsson.com

   Ulf A. Lindgren
   Ericsson AB
   Ericsson Research
   SE-417 56 Goteborg
   Sweden
   electronic mail: ulf.a.lindgren@ericsson.com

   Magnus Westerlund
   Ericsson AB
   Ericsson Research
   SE-164 80 Stockholm
   Sweden
   electronic mail: magnus.westerlund@ericsson.com

6. References

6.1. Normative

   [DLS1]     "Downloadable Sounds Level 1.1b", MMA/AMEI
               specificationv1.1b, Los Angeles, CA, USA, 2004.

   [DLS2]      "Downloadable Sounds Level 2.1", MMA/AMEI specification
               v1.0, Los Angeles, CA, USA, 2001.

   [MDLS]      "Mobile Downloadable Sounds 1.0", MMA specification
               v1.0, Los Angeles, CA, USA, 2004.

   [RFC4288]  Freed, N. and J. Klensin, "Media Type Specifications
               and Registration Procedures", BCP 13, RFC 4288,
               December 2005.

Frojdh, Lindgren and Westerlund                                 [Page 6]
INTERNET-DRAFT        draft-westerlund-mime-dls-01     February 10, 2006

6.2. Informative

   [RFC3548]  Josefsson, S., "The Base16, Base32, and Base64 Data
               Encodings", RFC 3548, July 2003.

IPR Notice

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed
   to pertain to the implementation or use of the technology described
   in this document or the extent to which any license under such
   rights might or might not be available; nor does it represent that
   it has made any independent effort to identify any such rights.
   Information on the procedures with respect to rights in RFC
   documents can be found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use
   of such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository
   at http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at ietf-
   ipr@ietf.org.

8. Copyright Notice

   Copyright (C) The Internet Society (2006).  This document is
   subject to the rights, licenses and restrictions contained in BCP
   78, and except as set forth therein, the authors retain all their
   rights.

   This document and the information contained herein are provided on
   an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE
   REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND
   THE INTERNET ENGINEERING TASK FORCE DISCLAIM 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 Internet-Draft expires in August 2006.

Frojdh, Lindgren and Westerlund                                 [Page 7]