--- 1/draft-ietf-6tisch-tsch-03.txt 2014-12-19 02:14:50.779292364 -0800 +++ 2/draft-ietf-6tisch-tsch-04.txt 2014-12-19 02:14:50.823293438 -0800 @@ -1,22 +1,22 @@ 6TiSCH T. Watteyne, Ed. Internet-Draft Linear Technology Intended status: Informational MR. Palattella -Expires: April 30, 2015 University of Luxembourg +Expires: June 22, 2015 University of Luxembourg LA. Grieco Politecnico di Bari - October 27, 2014 + December 19, 2014 Using IEEE802.15.4e TSCH in an IoT context: Overview, Problem Statement and Goals - draft-ietf-6tisch-tsch-03 + draft-ietf-6tisch-tsch-04 Abstract This document describes the environment, problem statement, and goals for using the IEEE802.15.4e TSCH MAC protocol in the context of LLNs. The set of goals enumerated in this document form an initial set only. Status of This Memo @@ -26,21 +26,21 @@ 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 30, 2015. + This Internet-Draft will expire on June 22, 2015. Copyright Notice Copyright (c) 2014 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 @@ -65,41 +65,41 @@ 4.7. Deterministic Behavior . . . . . . . . . . . . . . . . . 8 4.8. Scheduling Mechanisms . . . . . . . . . . . . . . . . . . 9 4.9. Secure Communication . . . . . . . . . . . . . . . . . . 9 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 6. Security Considerations . . . . . . . . . . . . . . . . . . . 9 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 8.1. Normative References . . . . . . . . . . . . . . . . . . 10 8.2. Informative References . . . . . . . . . . . . . . . . . 10 8.3. External Informative References . . . . . . . . . . . . . 13 - Appendix A. TSCH Protocol Highlights . . . . . . . . . . . . . . 16 - A.1. Timeslots . . . . . . . . . . . . . . . . . . . . . . . . 16 + Appendix A. TSCH Protocol Highlights . . . . . . . . . . . . . . 15 + A.1. Timeslots . . . . . . . . . . . . . . . . . . . . . . . . 15 A.2. Slotframes . . . . . . . . . . . . . . . . . . . . . . . 16 A.3. Node TSCH Schedule . . . . . . . . . . . . . . . . . . . 16 - A.4. Cells and Bundles . . . . . . . . . . . . . . . . . . . . 17 + A.4. Cells and Bundles . . . . . . . . . . . . . . . . . . . . 16 A.5. Dedicated vs. Shared Cells . . . . . . . . . . . . . . . 17 - A.6. Absolute Slot Number . . . . . . . . . . . . . . . . . . 18 + A.6. Absolute Slot Number . . . . . . . . . . . . . . . . . . 17 A.7. Channel Hopping . . . . . . . . . . . . . . . . . . . . . 18 - A.8. Time Synchronization . . . . . . . . . . . . . . . . . . 19 + A.8. Time Synchronization . . . . . . . . . . . . . . . . . . 18 A.9. Power Consumption . . . . . . . . . . . . . . . . . . . . 19 - A.10. Network TSCH Schedule . . . . . . . . . . . . . . . . . . 20 + A.10. Network TSCH Schedule . . . . . . . . . . . . . . . . . . 19 A.11. Join Process . . . . . . . . . . . . . . . . . . . . . . 20 - A.12. Information Elements . . . . . . . . . . . . . . . . . . 21 - A.13. Extensibility . . . . . . . . . . . . . . . . . . . . . . 21 + A.12. Information Elements . . . . . . . . . . . . . . . . . . 20 + A.13. Extensibility . . . . . . . . . . . . . . . . . . . . . . 20 Appendix B. TSCH Gotchas . . . . . . . . . . . . . . . . . . . . 21 B.1. Collision Free Communication . . . . . . . . . . . . . . 21 B.2. Multi-Channel vs. Channel Hopping . . . . . . . . . . . . 21 - B.3. Cost of (continuous) Synchronization . . . . . . . . . . 22 + B.3. Cost of (continuous) Synchronization . . . . . . . . . . 21 B.4. Topology Stability . . . . . . . . . . . . . . . . . . . 22 B.5. Multiple Concurrent Slotframes . . . . . . . . . . . . . 22 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 23 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22 1. Introduction IEEE802.15.4e [IEEE802154e] was published in 2012 as an amendment to the Medium Access Control (MAC) protocol defined by the IEEE802.15.4-2011 [IEEE802154] standard. IEEE802.15.4e will be rolled into the next revision of IEEE802.15.4, scheduled to be published in 2015. The Timeslotted Channel Hopping (TSCH) mode of IEEE802.15.4e is the object of this document. @@ -318,22 +318,22 @@ announces in its Enhanced Beacon. 3. Schedule transmissions of Enhanced Beacons to advertise the presence of the network. 4.3. Multi-Hop Topology RPL, given a weighted connectivity graph, determines multi-hop routes. The LLC needs to: - 1. Define a mechanism to gather topological information, which it - can then feed to RPL. + 1. Define a mechanism to gather topological information, node and + link state, which it can then feed to RPL. 2. Ensure that the TSCH schedule contains cells along the multi-hop routes identified by RPL. 3. Where applicable, maintain independent sets of cells to transport independent flows of data. 4.4. Routing and Timing Parents At all times, a TSCH node needs to have a time source neighbor it can @@ -427,22 +427,23 @@ This memo is an informational overview of existing standards, and does define any new mechanisms or protocols. It does describe the need for the 6TiSCH WG to define a secure solution. In particular, Section 4.1 describes security in the join process. Section 4.9 discusses data frame protection. 7. Acknowledgments Special thanks to Jonathan Simon for his review and valuable - comments. Thanks to the IoT6 European Project (STREP) of the 7th - Framework Program (Grant 288445). + comments. Thanks to Guillaume Gaillard and Dominique Barthel for + their in-depth review. Thanks to the IoT6 European Project (STREP) + of the 7th Framework Program (Grant 288445). 8. References 8.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 8.2. Informative References @@ -502,58 +503,52 @@ Address Autoconfiguration", RFC 4862, September 2007. [RFC3819] Karn, P., Bormann, C., Fairhurst, G., Grossman, D., Ludwig, R., Mahdavi, J., Montenegro, G., Touch, J., and L. Wood, "Advice for Internet Subnetwork Designers", BCP 89, RFC 3819, July 2004. [RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", RFC 2460, December 1998. - [I-D.ietf-6tisch-tsch] - Watteyne, T., Palattella, M., and L. Grieco, "Using - IEEE802.15.4e TSCH in an IoT context: Overview, Problem - Statement and Goals", draft-ietf-6tisch-tsch-02 (work in - progress), October 2014. + [I-D.ietf-6tisch-6top-interface] + Wang, Q., Vilajosana, X., and T. Watteyne, "6TiSCH + Operation Sublayer (6top) Interface", draft-ietf-6tisch- + 6top-interface-02 (work in progress), October 2014. [I-D.ietf-6tisch-architecture] Thubert, P., Watteyne, T., and R. Assimiti, "An Architecture for IPv6 over the TSCH mode of IEEE - 802.15.4e", draft-ietf-6tisch-architecture-03 (work in - progress), July 2014. + 802.15.4e", draft-ietf-6tisch-architecture-04 (work in + progress), October 2014. + + [I-D.ietf-6tisch-coap] + Sudhaakar, R. and P. Zand, "6TiSCH Resource Management and + Interaction using CoAP", draft-ietf-6tisch-coap-02 (work + in progress), December 2014. + + [I-D.ietf-6tisch-minimal] + Vilajosana, X. and K. Pister, "Minimal 6TiSCH + Configuration", draft-ietf-6tisch-minimal-04 (work in + progress), November 2014. [I-D.ietf-6tisch-terminology] Palattella, M., Thubert, P., Watteyne, T., and Q. Wang, "Terminology in IPv6 over the TSCH mode of IEEE 802.15.4e", draft-ietf-6tisch-terminology-02 (work in progress), July 2014. - [I-D.ietf-6tisch-minimal] - Vilajosana, X. and K. Pister, "Minimal 6TiSCH - Configuration", draft-ietf-6tisch-minimal-03 (work in - progress), October 2014. - - [I-D.ietf-6tisch-6top-interface] - Wang, Q., Vilajosana, X., and T. Watteyne, "6TiSCH - Operation Sublayer (6top) Interface", draft-ietf-6tisch- - 6top-interface-01 (work in progress), July 2014. - [I-D.wang-6tisch-6top-sublayer] Wang, Q., Vilajosana, X., and T. Watteyne, "6TiSCH Operation Sublayer (6top)", draft-wang-6tisch-6top- sublayer-01 (work in progress), July 2014. - [I-D.ietf-6tisch-coap] - Sudhaakar, R. and P. Zand, "6TiSCH Resource Management and - Interaction using CoAP", draft-ietf-6tisch-coap-01 (work - in progress), July 2014. - [I-D.thubert-roll-forwarding-frags] Thubert, P. and J. Hui, "LLN Fragment Forwarding and Recovery", draft-thubert-roll-forwarding-frags-02 (work in progress), September 2013. [I-D.tsao-roll-security-framework] Tsao, T., Alexander, R., Daza, V., and A. Lozano, "A Security Framework for Routing over Low Power and Lossy Networks", draft-tsao-roll-security-framework-02 (work in progress), March 2010. @@ -570,21 +565,21 @@ [I-D.ietf-roll-p2p-rpl] Goyal, M., Baccelli, E., Philipp, M., Brandt, A., and J. Martocci, "Reactive Discovery of Point-to-Point Routes in Low Power and Lossy Networks", draft-ietf-roll-p2p-rpl-17 (work in progress), March 2013. [I-D.ietf-roll-trickle-mcast] Hui, J. and R. Kelsey, "Multicast Protocol for Low power and Lossy Networks (MPL)", draft-ietf-roll-trickle- - mcast-09 (work in progress), April 2014. + mcast-11 (work in progress), November 2014. [I-D.thubert-6lowpan-backbone-router] Thubert, P., "6LoWPAN Backbone Router", draft-thubert- 6lowpan-backbone-router-03 (work in progress), February 2013. [I-D.sarikaya-core-sbootstrapping] Sarikaya, B., Ohba, Y., Moskowitz, R., Cao, Z., and R. Cragie, "Security Bootstrapping Solution for Resource- Constrained Devices", draft-sarikaya-core- @@ -600,21 +595,21 @@ Phinney, T., Thubert, P., and R. Assimiti, "RPL applicability in industrial networks", draft-phinney-roll- rpl-industrial-applicability-02 (work in progress), February 2013. 8.3. External Informative References [IEEE802154e] IEEE standard for Information Technology, "IEEE std. 802.15.4e, Part. 15.4: Low-Rate Wireless Personal Area - Networks (LR-WPANs) Amendament 1: MAC sublayer", April + Networks (LR-WPANs) Amendment 1: MAC sublayer", April 2012. [IEEE802154] IEEE standard for Information Technology, "IEEE std. 802.15.4, Part. 15.4: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications for Low-Rate Wireless Personal Area Networks", June 2011. [OpenWSN] "Berkeley's OpenWSN Project Homepage", . @@ -973,21 +969,21 @@ communication. This is done by building the schedule with dedicated cells in such a way that at most one node communicates with a specific neighbor in each slotOffset/channelOffset cell. Multiple pairs of neighbor nodes can exchange data at the same time, but on different frequencies. B.2. Multi-Channel vs. Channel Hopping A TSCH schedule looks like a matrix of width "slotframe size", S, and of height "number of frequencies", nFreq. For a scheduling - algorithm, these can be considered atomic "units" to schedule. In + algorithm, cells can be considered atomic "units" to schedule. In particular, because of the channel hopping nature of TSCH, the scheduling algorithm should not worry about the actual frequency communication happens on, since it changes at each slotframe iteration. B.3. Cost of (continuous) Synchronization When there is traffic in the network, nodes which are communicating implicitly re-synchronize using the data frames they exchange. In the absence of data traffic, nodes are required to synchronize to @@ -1028,27 +1024,26 @@ 2. Lower slotframe identifiers take precedence over higher slotframe identifiers. In the example above, the node would transmit to node B on slotframe 2. Authors' Addresses Thomas Watteyne (editor) Linear Technology - 30695 Huntwood Avenue - Hayward, CA 94544 + 32990 Alvarado-Niles Road, Suite 910 + Union City, CA 94587 USA Phone: +1 (510) 400-2978 Email: twatteyne@linear.com - Maria Rita Palattella University of Luxembourg Interdisciplinary Centre for Security, Reliability and Trust 4, rue Alphonse Weicker Luxembourg L-2721 LUXEMBOURG Phone: +352 46 66 44 5841 Email: maria-rita.palattella@uni.lu