H.248/MEGACO Registration Procedures
RFC 5615

Network Working Group                                          C. Groves
Request for Comments: 5615                                NTEC Australia
BCP: 151                                                          Y. Lin
Category: Best Current Practice                                   Huawei
                                                             August 2009

                 H.248/MEGACO Registration Procedures

Abstract

   This document updates the H.248/MEGACO IANA Package registration
   procedures in order to better describe the Package registration
   process and to provide a more formal review and feedback process.

Status of This Memo

   This document specifies an Internet Best Current Practices for the
   Internet Community, and requests discussion and suggestions for
   improvements.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (c) 2009 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents in effect on the date of
   publication of this document (http://trustee.ietf.org/license-info).
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.

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Table of Contents

   1. Introduction ....................................................2
   2. Conventions Used in This Document ...............................4
   3. Formal Syntax ...................................................4
   4. Security Considerations .........................................5
   5. IESG Expert Reviewer Considerations .............................6
      5.1. Appointment of the IESG H.248/MEGACO Expert ................6
      5.2. Package Registration Procedure .............................6
      5.3. Error Code Registration Procedure ..........................8
      5.4. ServiceChange Reason Registration Procedure ................9
      5.5. Profile Name Registration Procedure .......................10
   6. IANA Considerations ............................................11
      6.1. New IANA Package Registration .............................11
      6.2. IANA Error Code Registration ..............................12
      6.3. IANA ServiceChange Reason Registration ....................12
      6.4. IANA Profile Name Registration ............................12
   7. References .....................................................13
      7.1. Normative References ......................................13
      7.2. Informative References ....................................13

1.  Introduction

   Since the initial development of H.248/MEGACO, a number of
   organizations have made use of the H.248/MEGACO protocol Package
   mechanism in order to allow a certain function to be controlled by
   H.248/MEGACO.  The H.248/MEGACO Package mechanism was introduced, in
   part, to allow organizations who had an in-depth knowledge in a
   particular functional area to independently produce a Package on this
   functionality.  This acknowledged the fact that neither the IETF
   MEGACO Working Group nor the ITU-T Study Group 16 possessed in-depth
   knowledge in all areas.  Whilst this approach has been successful in
   the number and range of Packages produced, in some cases these
   Packages were/are not fully aligned with H.248/MEGACO principles.
   Once a Package has been published and registered, it is problematic
   to rectify any issues.

   The introduction of problems/inconsistencies was caused, in part, by
   the fact that the Packages were not fully reviewed by H.248/MEGACO
   experts.  In fact, the IANA H.248/MEGACO registration process did not
   actually specify that an in-depth review should take place.

   The current H.248/MEGACO Package registration process was defined
   when the ITU-T Study Group 16 and the IETF MEGACO Working Groups were
   both active in H.248/MEGACO standardization and produced nearly all
   the registered Packages.  Packages were reviewed in the IETF MEGACO
   Working Group and the Working Group chair was the IESG-appointed

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   expert in charge of the review of the requests for H.248 Package
   registration.  This meant that H.248 Packages underwent an informal
   review before being registered.  However, this has changed.

   The current situation is that now the IETF MEGACO Working Group is
   disbanded and new H.248/MEGACO development typically occurs through
   Question 3 of ITU-T Study Group 16 (notwithstanding email discussion
   on the IETF MEGACO mailing list).  This move to ITU-T-defined
   Recommendations is discussed in [RFC5125].

   Given this situation, it is appropriate that the H.248/Package
   definition and IANA registration rules are updated to introduce a
   formal review step before the Package registration process is
   completed and, ideally, before the Package is published.  This
   process will only be applicable to public Packages.

   As part of the Package development process, Package developers are
   encouraged to send their Package for review to the ITU-T Study Group
   Question Rapporteur responsible for the H.248 sub-series of
   Recommendations (ITU-T Question 3 of Study Group 16 at the time of
   writing).  When registering the Package with IANA, Package developers
   are required to send a copy of the Package for review by the IESG-
   appointed expert.  It is recommended to register the Package before
   final approval by the group in question, in order to solicit feedback
   on the quality of their Package.  Wherever possible, this review will
   be done in conjunction with other H.248/MEGACO experts (e.g., in
   ITU-T Q.3/16 and/or the MEGACO mailing list).

   The existing IANA Package registration process is a two-step process.
   When Packages are first registered, they receive the status of "In
   Progress (IP)".  This allows Package developers to request a
   PackageID before the document is fully approved.  When the document
   is approved, then a change of status to "Final" may be requested.
   The new procedure introduces the step that the IESG-appointed expert
   is consulted before a change of status is made.  If the Package has
   been reviewed and is acceptable, then the status may be changed to
   "Final".  However, if the Package has not been provided for review or
   has outstanding comments, then the status SHALL remain at "IP".

   The goal of the updated text is to define a process that provides a
   timely technical review of Packages to ensure that H.248/MEGACO
   Packages are of good quality and to minimize duplication.

   The "Error Code", "ServiceChange Reason", and "Profile Name"
   registration procedures have been included for completeness and to
   make explicit the role of the IESG reviewer.  These procedures align

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   with the considerations documented in [H248amm1] and with [RFC3525]
   (with the exception of Profile Names, which did not appear in the
   [RFC3525] version).

2.  Conventions Used in This Document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

3.  Formal Syntax

   The following syntax specification uses the Augmented Backus-Naur
   Form (BNF) as described in [RFC5234].

   Text-encoded PackageIDs shall conform to the "PackageName" encoding
   in H.248.1 [H248amm1] Annex B, which is repeated below for
   convenience:

   Copyright (c) 2009 IETF Trust and the persons identified as authors
   of the code.  All rights reserved.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   - Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.

   - Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in
     the documentation and/or other materials provided with the
     distribution.

   - Neither the name of Internet Society, IETF or IETF Trust, nor the
     names of specific contributors, may be used to endorse or promote
     products derived from this software without specific prior
     written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   'AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

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   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

     PackageName   = NAME

     NAME       = ALPHA *63(ALPHA / DIGIT / "_")

   Note: A digit is not allowed as the first character of a Package
   name.

4.  Security Considerations

   Updating the IANA H.248/MEGACO Package registration procedures has no
   additional security implications.  Security for the H.248/MEGACO
   protocol over IP transports is discussed in H.248.1 Section 10
   [H248amm1].

   As of this date, there have been no recorded security issues arising
   out of the registration or use of Packages.  Whilst Packages may
   define extra procedures and code points, these are done within the
   framework of the core H.248.1 specification.  It is not possible to
   update the H.248.1 core protocol through a Package specification.
   The use of the H.248.1 core protocol is agreed upon between a Media
   Gateway Controller (MGC) and a Media Gateway (MG).  H.248
   ServiceChange procedures establish a H.248 control association
   between the MGC and MG.  To establish an association, there must be a
   level of trust between the MGC and MG.  In the context of this
   control (and trust) association, the elements
   (properties/signals/events/statistics) from the Packages are conveyed
   between the MGC and MG.  An MGC or MG will only act upon elements
   that it knows.  If it does not understand a PackageID or Package
   element, then an error response is returned only in the context of
   the control association.

   If a malicious Package specification is implemented in an MGC or MG,
   it would be unlikely to cause problems.  As H.248 is a master slave
   protocol, if the malicious Package was implemented in the MGC and not
   the MG, there would be no action because the MG would not understand
   the PackageID (and elements).  If the malicious Package was
   implemented on the MG, there would be no effect because the MGC would
   never command the MG to use it.  If the malicious Package was
   implemented in both the MGC and MG, then there's a wider, non-H.248
   issue in that someone has managed to install software on both the MGC
   and the MG.  It is highly unlikely for such a person to ask IANA for
   a PackageID when they could use any one they want.

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   Therefore, it is in this respect that updates to the IANA
   H.248/MEGACO Package registration procedures are deemed to have no
   additional security impacts.

   Requesters and the Expert Reviewer should ensure that the Package
   does not introduce any additional security issues.  Requesters for
   public Packages for a particular standards development organization
   must be authorized by that organization to request a Package
   registration.

5.  IESG Expert Reviewer Considerations

   For public registered Packages, Error Codes, ServiceChangeReasons,
   and Profile Names, review by an Expert Reviewer is required before
   IANA performs a registration.  Private Packages do not require the
   same level of review.  The sections below outline the considerations
   for Expert Review.

5.1.  Appointment of the IESG H.248/MEGACO Expert

   The IESG shall remain responsible for allocating the H.248/MEGACO
   expert.  It is recommended that this person be involved in ongoing
   H.248/MEGACO development.  As such, it is recommended that
   identification of the IESG expert be done in consultation with the
   ITU-T Question/Study Group responsible for the H.248 sub-series of
   Recommendations (ITU-T Q.3/16 at the time of writing).

5.2.  Package Registration Procedure

   Package requesters are encouraged to review their work against
   H.248.1 Section 12 [H248amm1], "Package Definition", and are
   encouraged to use the "Package Definition Template" provided in
   H.248.1 Appendix II.

   The process for registering a public Package is deemed to be
   "specification required" as per [RFC5226].  As such, once the initial
   checks occur, Package requesters for public Packages under
   development shall send the Package text to IANA.  They are also
   encouraged to send the package to the ITU-T Question/Study Group
   responsible for the H.248 sub-series of Recommendations (ITU-T Q.3/16
   at the time of writing) for review.  Updated contact information can
   be found in the latest version of the H.248 Sub-series Implementors'
   Guide.  This should occur as soon as practicable after the rough
   draft of the definition is completed and at least before the Package
   is approved, in order to ensure the Package is consistent with H.248
   methodologies and Package-design principles.

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   In order to register private Packages, a specification is not
   required but is encouraged.

   Package requesters are encouraged to request registration as early as
   practicable in the design process, to reserve a binary ID.  Binary
   IDs shall be published in the document defining the Package.

   Once the initial or final request for a Package registration is
   received by IANA, it will be forwarded to the IESG-appointed expert
   for review.  During the review, the input Package and details will be
   compared to the Package template for completeness, as well as being
   compared against protocol syntax and procedures.  It will be compared
   against existing work to see that it does not duplicate existing
   functionality.  It will be reviewed to see that any potential
   security issues are addressed.  The Expert Reviewer will then work
   towards a resolution of any issues with the Package requester.  The
   IESG-appointed expert may complete the review in consultation with
   other H.248 experts (i.e., currently Question 3 of ITU-T Study Group
   16 and via email to IETF MEGACO email list).  If the Package is
   deemed suitable, the IESG-appointed expert shall issue a statement
   indicating approval, copied to IANA.

   The IESG Expert Reviewer will ensure the following considerations are
   met to register a Package with the IANA:

   1) A unique string name, unique serial number and version number are
      registered for each Package.  The string name is used as the
      PackageID for text encoding.  The serial number is used as the
      PackageID for binary encoding.  Public Packages MUST be given
      serial numbers in the range 0x0001 to 0x7fff.  Private Packages
      MUST be given serial numbers in the range 0x8000 to 0xffff.
      Serial number 0 is reserved.  The unique string name and unique
      serial number MAY either be requested by the Package requester or,
      if not requested, assigned by the IANA.

   2) The Package requester shall provide a contact name and an email
      and postal address for that contact.  The contact information
      shall be updated by the defining organization as necessary.

   3) The public Package requester shall provide a reference to a
      document that describes the Package, which should be public:

      a) The document shall specify the version of the Package that it
         describes.

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      b) If the document is public, it should be located on a public web
         server and should have a stable URL.  The site should provide a
         mechanism to provide comments and appropriate responses should
         be returned.

      c) If the document is not public, it must be made available for
         review by the IESG-appointed expert (without requiring a non-
         disclosure agreement (NDA)) at the time of the application.

      Note: The document does not have to be publicly available at the
      time of the registration request; however, the document shall be
      provided and available for review by the IESG-appointed expert.
      Once approved by a standards body, the Package SHOULD be made
      publicly available, however the Package MAY remain not public.

      For private Packages, a contact email address for the Package
      registration shall be provided.

   4) Packages registered by other than recognized standards bodies
      shall have a minimum Package name length of 8 characters.

   5) Package names are allocated on a first-come, first-served basis if
      all other conditions are met.

   Status - "In Progress" indicates that the Package has not been fully
   reviewed and approved and, therefore, may contain errors or may not
   be consistent with H.248 principles.  "Final" indicates that the
   Package has been reviewed and approved and is stable.  New Packages
   shall be registered with a status of "IP".  Once the Package has been
   finalized (i.e., approved according to the procedures of the Package
   requester's organization), they should contact IANA in order to
   update the status to "Final".

   Once the IESG-appointed expert has determined that the registration
   is appropriate, they will advise the IANA to register the Package.

   The IANA will assign a serial number to each Package meeting the
   conditions of registration (except for an update of an existing
   Package, which retains the serial number of the Package it is
   updating), in consecutive order of registration.

5.3.  Error Code Registration Procedure

   Error Code requesters shall send a request to the IANA to register
   the Error Code.  Documentation addressing the considerations below
   shall be provided (i.e., specification required as per [RFC5226]).
   The IANA shall then forward the request to the IESG-appointed expert
   for review.

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   The following considerations shall be met to register an Error Code
   with IANA:

   1) An error number and a one-line (80-character maximum) string are
      registered for each error.

   2) A complete description of the conditions under which the error is
      detected shall be included in a publicly available document.  The
      description shall be sufficiently clear to differentiate the error
      from all other existing Error Codes.

   3) The document should be available on a public web server and should
      have a stable URL.

   4) Error numbers registered by recognized standards bodies shall have
      3- or 4-character error numbers.

   5) Error numbers registered by all other organizations or individuals
      shall have 4-character error numbers.

   6) Only the organization or individual that originally defined it (or
      their successors or assigns) can modify an error-number
      definition.  If the modification leads to a change in the Error
      Code number, Error Code name or error string, the Error Code
      modifier shall send a request to IANA to register the update.
      This request shall be treated as a new Error Code request, which
      will involve an Expert Review.

   Once the IESG-appointed expert has determined that the registration
   is appropriate, they will advise the IANA to register the Error Code.

5.4.  ServiceChange Reason Registration Procedure

   ServiceChange Reason requesters shall send a request to the IANA to
   register the ServiceChange Reason.  Documentation addressing the
   considerations below shall be provided (i.e., specification required
   as per [RFC5226]).  The IANA shall then forward the request to the
   IESG-appointed expert for review.

   The following considerations shall be met to a register ServiceChange
   Reason with IANA:

   1) A reason number and a one-phrase (80-character maximum) unique
      string are registered for each reason.

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   2) A complete description of the conditions under which the reason is
      used shall be included in a publicly available document.  The
      description shall be sufficiently clear to differentiate the
      reason from all other existing ServiceChange Reasons.

   3) The document should be available on a public web server and should
      have a stable URL.

   Once the IESG-appointed expert has determined that the registration
   is appropriate, they will advise IANA to register the ServiceChange
   Reason.

5.5.  Profile Name Registration Procedure

   Profile Name requesters shall send a request to the IANA to register
   the Profile Name.  Documentation addressing the considerations below
   shall be provided.  The IANA shall then forward the request to the
   IESG-appointed expert for review.

   The following considerations shall be met to register a profile with
   IANA:

   1) A unique string name and version number (version may be omitted
      when the Profile Name contains a wildcard) is registered for each
      profile.

   2) A contact name and email and postal address for that contact shall
      be specified.  The contact information shall be updated by the
      defining organization as necessary.

   3) Profiles registered by other than recognized standards bodies
      shall have a minimum Profile Name length of 6 characters.

   4) Profile Names containing a wildcard "*" on the end of their names
      shall be accepted if the first 6 characters are fully specified.
      It is assumed that the organization that was issued with the
      Profile Name will manage the namespace associated with the
      wildcard.  IANA shall not issue other profiles names within
      "name*" range.

   All Profile Names are first-come, first-served if all other
   conditions are met.

   Once the IESG-appointed expert has determined that the registration
   is appropriate, they will advise IANA to register the Profile Name.

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6.  IANA Considerations

   This document describes an updated Package registration procedure.
   [RFC5226] has been considered in making the updates.  This document
   does not alter the tabular Package, Error Code, and ServiceChange
   Reason information in the H.248/MEGACO Packages registry.

   The "Error Code", "ServiceChange Reason", and "Profile Name" IANA
   considerations have been included for completeness.  These
   considerations align with the considerations documented in H.248.1
   [H248amm1] and with [RFC3525] (with the exception of Profile Names,
   which did not appear in the [RFC3525] version).

6.1.  New IANA Package Registration

   On the request for an initial or final Package registration, the IANA
   shall forward the received information (i.e., the Package text
   (specification required as per [RFC5226])) to the IESG-appointed
   expert for review (see Section 5.2).

   After the review, when instructed by the IESG-appointed expert, the
   IANA shall register the following information in the "H.248/MEGACO
   Packages" registry as described below:

   1. Serial Number (identity used for Binary Encoding, also known as
      Binary ID)

   2. Text Name (identity used for Text Encoding, see Section 3 for the
      syntax)

   3. Package version

   4. Extension information - Binary ID and Package version

   5. Status* - IP ("In Progress") or Final

   6. Package name, Reference, and Contact information

   IANA will maintain the currency and public availability of the
   tabulation of public and private Packages.  Packages will be listed
   in increasing order of serial number.  The latest Package version
   will be entered, replacing the previous version in the registry.

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6.2.  IANA Error Code Registration

   On the request for an Error Code registration, the IANA shall forward
   the received information (i.e., the Error Code text and required
   specification) to the IESG-appointed expert for review (see Section
   5.3).

   When instructed by the IESG-appointed expert, the IANA shall register
   the following information in the "H.248/MEGACO Packages" registry as
   described below:

   1. Error Code Number

   2. Error Code Text String

   3. Reference

6.3.  IANA ServiceChange Reason Registration

   On the request for a ServiceChange Reason registration, the IANA
   shall forward the received information (i.e., the ServiceChange
   Reason text and required specification) to the IESG-appointed expert
   for review (see Section 5.4).

   When instructed by the IESG-appointed expert, the IANA shall register
   the following information in the "H.248/MEGACO Packages" registry as
   described below:

   1. ServiceChange Reason Number

   2. ServiceChange Reason Text String

   3. Reference

6.4.  IANA Profile Name Registration

   On the request for a Profile Name registration, the IANA shall
   forward received information to the IESG-appointed expert for review
   (see Section 5.5).

   When instructed by the IESG-appointed expert, the IANA shall register
   the following information in the "H.248/MEGACO Packages" registry as
   described below:

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   1. Profile Name

   2. Version

   3. Reference/Contact

7.  References

7.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC5234]  Crocker, D., Ed., and P. Overell, "Augmented BNF for
              Syntax Specifications: ABNF", STD 68, RFC 5234, January
              2008.

   [H248amm1] International Telecommunication Union, "Gateway control
              protocol: Version 3", Amendment 1 to ITU-T Recommendation
              H.248.1, April 2008.

7.2.  Informative References

   [RFC3525]  Groves, C., Ed., Pantaleo, M., Ed., Anderson, T., Ed., and
              T. Taylor, Ed., "Gateway Control Protocol Version 1", RFC
              3525, June 2003.

   [RFC5125]  Taylor, T., "Reclassification of RFC 3525 to Historic",
              RFC 5125, February 2008.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

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Authors' Addresses

   Christian Groves
   NTEC Australia
   Newport, Victoria
   Australia

   EMail: Christian.Groves@nteczone.com

   Yangbo Lin
   Huawei Technologies Co., Ltd.
   Shenzhen, Guangdong
   P. R. China

   EMail: linyangbo@huawei.com

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