Network Working Group T. Kivinen Internet-Draft INSIDE Secure Intended status: Informational P. Kinney Expires: April 28, 2017 Kinney Consulting LLC October 25, 2016 IEEE 802.15.4 Information Element for IETF draft-kivinen-802-15-ie-04.txt Abstract IEEE Std 802.15.4 defines Information Elements (IEs) that can be used to extend 802.15.4 in an interoperable manner. The IEEE 802.15 Assigned Numbers Authority (ANA) manages the registry of the Information Elements. This document formulates a request for ANA to allocate a number from that registry for IETF, and describes how the IE is formatted to provide subtypes. 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 April 28, 2017. Copyright Notice Copyright (c) 2016 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 include Simplified BSD License text as described in Section 4.e of Kivinen & Kinney Expires April 28, 2017 [Page 1] Internet-Draft IEEE 802.15.4 Information Element for IETF October 2016 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Working Groups Benefitting from the IETF 802.15.4 IE . . . . 3 4. IETF IE Subtype Format . . . . . . . . . . . . . . . . . . . 3 5. Request to allocate IETF IE . . . . . . . . . . . . . . . . . 4 6. Security Considerations . . . . . . . . . . . . . . . . . . . 4 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 4 8.1. Normative References . . . . . . . . . . . . . . . . . . 5 8.2. Informative References . . . . . . . . . . . . . . . . . 5 Appendix A. Vendor Specific IE in IEEE 802.15.4 . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction IEEE Std. 802.15.4 [IEEE-802-15-4] defines Information Elements (IEs) that can be used to extend 802.15.4 in an interoperable manner. There are two different IE types, Header IE and Payload IE. A Header IE is part of the Medium Access Control (MAC) header; it is never encrypted, but may be authenticated. Most of the Header IE processing is done by the MAC, and IETF protocols should not have any direct effect on that processing. A Payload IE is part of the MAC payload, and may be encrypted and authenticated. IETF protocols will need to insert information in the 802.15.4 frames; the 802.15.4 enables that by including one or more payload IEs in the frame that will contain the information. For this purpose the IETF requests a dedicated Payload IE from the IEEE 802.15 Assigned Numbers Authority (ANA) [IEEE-802-15-ANA]. The current 802.15 ANA database can be found at [IEEE-802-15-ANA-DB]. The 802.15.4 operations manual [IEEE-802-15-OPS] describes how a standardization organization (SDO) may request an allocation of one IE. To make this request the SDO has to provide (i) the reason for the request, (ii) a description of the protocol format that shows an appropriate subtype capability, and (iii) an agreement that only one IE number will be allocated for use by the SDO. This document provides the information needed for the request. Kivinen & Kinney Expires April 28, 2017 [Page 2] Internet-Draft IEEE 802.15.4 Information Element for IETF October 2016 2. Terminology 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. Working Groups Benefitting from the IETF 802.15.4 IE There are several IETF working groups such as 6TiSCH, 6lo, CoRE etc, which could benefit from the IETF IE. The 6TiSCH working group has already expressed the need for the IE, and this allocation is expected to satisfy that need. 4. IETF IE Subtype Format The maximum length of the Payload IE content is 2047 octets, and 802.15.4 frame contains a list of payload IEs. A single frame can have multiple payload IEs, terminated with the payload IE terminator, which may then be followed by the payload. Because the frame contains a list of payload IEs, there is no need for this document to specify the internal structure inside the IETF IE. The Payload IE format of IEEE 802.15.4 contains the Length field. The length of the subtype content can be calculated from the IEEE 802.15.4 Payload IE Length field of the IETF IE. The format of the IETF IE is as follows: 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Subtype ID | | +-+-+-+-+-+-+-+-+ | ~ subtype content ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: IETF IE Subtype Format o Subtype ID is the IANA allocated number specifying the subtype of the IETF IE. Value 0 is reserved for future extensibility, i.e., in case a longer subtype ID field is needed. o Subtype content is the actual content of the information element, and its length can be calculated from the Length field of the IETF IE. Kivinen & Kinney Expires April 28, 2017 [Page 3] Internet-Draft IEEE 802.15.4 Information Element for IETF October 2016 One IEEE 802.15.4 frame MAY contain multiple IETF IEs with the same or different subtypes. 5. Request to allocate IETF IE The IETF requests that the 802.15 Working Group allocate an ID for a Payload IE for IETF use. Furthermore the IETF understands that only one ID will be issued to it. 6. Security Considerations This document creates an IANA registry for IETF IE subtype ID (see Section 7). The security of the protocols using the IEs MUST be described in the documents requesting allocations from this registry. The IEEE Std 802.15.4-2015 [IEEE-802-15-4] contains methods where security of the IE can be enforced when a frame is received, but this is only per IE type. Therefore, all IETF IEs will have same security level requirements regardless of the subtype ID used. This can cause issues if different security processing would be needed and any of those IEs would need to be processed in the MAC level. Since all IETF protocols should operate at a higher level than the MAC level, the higher layer processing for these IEs SHOULD perform separate security policy checking based on the IETF IE subtype ID in addition to the checks done by the MAC. 7. IANA Considerations This document creates a new registry for IETF IE subtype IDs registry: Value Subtype ID 0 Reserved 1-200 Unassigned 201-255 Experimental Use Any change or addition to this registry requires expert review. Note, that there is Vendor specific IEs already defined in the IEEE 802.15.4 (see Appendix A), and because of this, there is no need to reserve any subtype IDs for the vendor-specific uses. 8. References Kivinen & Kinney Expires April 28, 2017 [Page 4] Internet-Draft IEEE 802.15.4 Information Element for IETF October 2016 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, . 8.2. Informative References [IEEE-802-15-4] "IEEE Standard for Low-Rate Wireless Personal Area Networks (WPANs)", IEEE Standard 802.15.4, 2015. [IEEE-802-15-ANA] "IEEE 802.15 Assigned Numbers Authority", . [IEEE-802-15-ANA-DB] "IEEE 802.15 ANA database", . [IEEE-802-15-OPS] "IEEE 802.15 Operations Manual", . Appendix A. Vendor Specific IE in IEEE 802.15.4 IEEE 802.15.4 has already several numbers for different Vendor Specific IE types. There is one for the Vendor Specific Header IE for Header IEs. There is one incorrectly named Vendor Specific Nested IE for Payload IEs, and there is another one with exactly the same name, but under the MLME Nested IE long format. All of the Vendor Specific IEs start with a 3-octet vendor OUI to identify the organization. Authors' Addresses Tero Kivinen INSIDE Secure Eerikinkatu 28 HELSINKI FI-00180 FI Email: kivinen@iki.fi Kivinen & Kinney Expires April 28, 2017 [Page 5] Internet-Draft IEEE 802.15.4 Information Element for IETF October 2016 Pat Kinney Kinney Consulting LLC Email: pat.kinney@kinneyconsultingllc.com Kivinen & Kinney Expires April 28, 2017 [Page 6]