CoRE Working Group C. Groves Internet-Draft Intended status: Standards Track W. Yang Expires: October 21, 2017 Huawei April 19, 2017 Addition of organisation prefix to RFC6690 IANA CoRE parameters registration draft-groves-core-rfc6690up-01 Abstract [RFC6690] defines the resource type 'rt' and interface description 'if' link attributes and defines procedures for registering values. Currently each 'rt' and 'if' attribute value must be registered with IANA. This specification updates the process to enable organisation prefixes to be registered allowing organisations to manage their own namespace within a certain set of rules. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on October 21, 2017. Copyright Notice Copyright (c) 2017 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 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must Groves & Yang Expires October 21, 2017 [Page 1] Internet-Draft Prefix for CoRE parameter reg April 2017 include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Requirements Language . . . . . . . . . . . . . . . . . . . . 2 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Organisation Prefix . . . . . . . . . . . . . . . . . . . . . 4 4. Security Considerations . . . . . . . . . . . . . . . . . . . 5 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 5.1. Constrained RESTful Environments (CoRE) Parameters Registry Update . . . . . . . . . . . . . . . . . . . . . 5 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 6 7. Changelog . . . . . . . . . . . . . . . . . . . . . . . . . . 6 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 8.1. Normative References . . . . . . . . . . . . . . . . . . 7 8.2. Informative References . . . . . . . . . . . . . . . . . 7 8.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7 1. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 2. Introduction [RFC6690] "Constrained RESTful Environments (CoRE) Link Format" defines the Resource Type 'rt' and Interface Description 'if' link attributes. In order to co-ordinate the use of these attributes, sections 7.4 and 7.5/[RFC6690] establish IANA registries to register link attribute values for 'rt' and 'if'. In order to register a new 'rt' and 'if' link attribute value the [RFC5226] "Specification Required" process is followed for each value. As part of the process a designated expert will examine the specification to enforce a number of requirements including: o Registration values MUST be related to the intended purpose of these attributes as described in Section 3/[RFC6690]. o Registered values MUST conform to the ABNF reg-rel-type definition of Section 2/[RFC6690], meaning that the value starts with a lowercase alphabetic character, followed by a sequence of Groves & Yang Expires October 21, 2017 [Page 2] Internet-Draft Prefix for CoRE parameter reg April 2017 lowercase alphabetic, numeric, ".", or "-" characters, and contains no white space. o It is recommended that the period "." character be used for dividing name segments and that the dash "-" character be used for making a segment more readable. Example Interface Description values might be "core.batch" and "core.link-batch". o URIs are reserved for free use as extension values for these attributes and MUST NOT be registered. The IANA CoRE resource type and interface description registry can be found at: IANA CoRE Registry [1]. Given the scope of the Internet of Things (IoT) the potential number of resource types (and to a lesser extent interface types) is potentially quite large. This would lead to a large number of requests for designated expert review. It would also mean additional work for the IANA to process each request. The current trend for the definition of resource types and interface descriptions is that a few standards organisations have defined a large number of values. For example the "OIC Resource Type Specification v1.1.0" [OICResSpec] contains 64 resource types. ETSI oneM2M also defines a large number of resource types. For example is "Home Appliances Information Model and Mapping" [oneM2MTS0023]. The Open Mobile Alliance (OMA) also make use of resources types. The above three organisations also have their own registry and procedures for adding resource types. Trying to keep the IANA registry aligned with the individual organisation registries would also add additional burden. A significant amount of work could be saved by allowing organisations to register a prefix under which they can administer their own resources negating the need for the IANA and the designated IANA expert to be involved for each resource registration. There were discussions ath the IETF#97 meeting in Seoul about how to tackle this issue. There were broadly two camps in the discussion: 1 - Prefixes are a bad idea as they discourage people from resource re-use and create little "kingdoms". Groves & Yang Expires October 21, 2017 [Page 3] Internet-Draft Prefix for CoRE parameter reg April 2017 2 - Prefixes are OK. They've been used before and people will coalesce on a common set eventually. Clearly some sort of middle ground is needed to move forward. Clearly resource re-use is a valid goal. It order for this to occur organisations/people requesting a new resource type would need to consider the existing resource types and see if it is applicable to them. Presumably if they can't use an existing type then they must have a reason why? One approach could be to introduce a new step into the registration process where the requester must specify any similar resources and why they cannot be used. This does of course add extra burden on the requester to document it and extra burden on the expert to evaluate it. Then there is the issue of what suffices for the analysis and what are the criteria for the expert to accept it? This may not result in reduced registrations but instead create more workload for registrations. Currently all the rt registrations have been from standards organisations not individuals. The process for registration needs to be simple enough that people/companies have a incentive to register than rather than simply use and squat on a name without registering it. It does have to be noted that today there is nothing stopping people/ organisations from duplicating resources in their registration. An organisational prefix would not make this worse. *Editor's note: Interface descriptions should be considered* This specification updates the [RFC6690] IANA registration procedures to allow the possibility to register a pre-fix. 3. Organisation Prefix As indicated by [RFC6690] registered values MUST conform to the ABNF reg-rel-type definition, meaning that the value starts with a lowercase alphabetic character. Therefore an organisation registering a prefix MUST register a lowercase alphabetic sequence of characters. It MUST be followed by a ".". For example: "foo." This will allocate the namespace "foo." to the organisation. The organisation will then be responsible for maintaining resources within this name space. Groves & Yang Expires October 21, 2017 [Page 4] Internet-Draft Prefix for CoRE parameter reg April 2017 E.g. "foo.sensor", "foo.actuator" could be allocated without requiring registration with IANA. 4. Security Considerations This specification updates the [RFC6690] IANA Considerations. No additional protocol security impacts to what is already described in [RFC6690] are foreseen. The use of organisational prefixes introducing the possibility that people request prefixes for an organisation that they do not represent. The IANA considerations in this specification require that the designated expert determine if the person requesting a prefix represents the organisation related to the prefix. 5. IANA Considerations 5.1. Constrained RESTful Environments (CoRE) Parameters Registry Update This specification updates the Constrained RESTful Environments (CoRE) Parameter Registry by allowing the registration of an organisation prefix for Resource Type (rt=) and Interface Description (if=) Link Target Attribute values. Organisation prefixes are registered by using the Specification Required policy (see [RFC5226], which requires review by a designated expert appointed by the IESG or their delegate. The designated expert will enforce the following requirements: o The registered prefix MUST conform to the ABNF reg-rel-type definition of Section 2/[RFC6690], meaning that the value starts with a lowercase alphabetic character followed by a period ".". o The registered prefixes are assigned on a first come first served basis. o Prefixes must be requested by a representative of the organisation applying for the prefix and must be representative of the organisation. E.g. organisation "foo" trying to register "ietf." would not be representative. The specification MUST: o Specify the procedures for registering values within the prefixed namespace. It ideally SHOULD provide a link where current and future registered values may be found. Groves & Yang Expires October 21, 2017 [Page 5] Internet-Draft Prefix for CoRE parameter reg April 2017 o Indicate that registered values within the prefixed namespace MUST conform to the ABNF reg-rel-type definition of Section 2/[RFC6690]. This means that the prefix MUST be followed by a sequence of lowercase alphabetic, numeric, ".", or "-" characters, and contains no white space. Note: It is not recommended to immediately follow the prefix with an additional period ".", e.g. "foo..". o Use the recommendation that the period "." character be used for dividing name segments and that the dash "-" character be used for making a segment more readable. Example Interface Description values might be "core.batch" and "core.link-batch". Registration requests consist of the completed registration template below, with the reference pointing to the required specification. To allow for the allocation of values prior to publication, the designated expert may approve registration once they are satisfied that a specification will be published. The registration template for both sub-registries is: o Prefix Value: o Description: o Reference: o Notes: [optional] Registration requests should be sent to the core-parameters@ietf.org mailing list, marked clearly in the subject line (e.g., "NEW RESOURCE TYPE PREFIX - example" to register an "example" relation type or "NEW INTERFACE DESCRIPTION PREFIX - example" to register an "example" Interface Description). Handling and the decision process is as per section 7.4/[RFC6690]. 6. Acknowledgements TBD 7. Changelog draft-groves-core-rfc6690up-01: o Keepalive update. No changes. Groves & Yang Expires October 21, 2017 [Page 6] Internet-Draft Prefix for CoRE parameter reg April 2017 8. References 8.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, DOI 10.17487/RFC5226, May 2008, . [RFC6690] Shelby, Z., "Constrained RESTful Environments (CoRE) Link Format", RFC 6690, DOI 10.17487/RFC6690, August 2012, . 8.2. Informative References [OICResSpec] "OIC Resource Type Specification v1.1.0", 2016, . [oneM2MTS0023] "TS 0023 v2.0.0 Home Appliances Information Model and Mapping", 2015, . 8.3. URIs [1] http://www.iana.org/assignments/core-parameters/core- parameters.xhtml Authors' Addresses Christian Groves Australia Email: cngroves.std@gmail.com Weiwei Yang Huawei P.R.China Email: tommy@huawei.com Groves & Yang Expires October 21, 2017 [Page 7]