# Minutes, IETF 96 LPWAN WG-forming BoF Meeting # Note: this document is formatted using Markdown (https://daringfireball.net/projects/markdown/) Agenda and Meeting information ============================== ``` Meeting : IETF96 Monday, July 18, 2016 (CEST) Time : 15:40-17:40 Monday Afternoon session I (120min) Location : Charlottenburg II/III, Intercontinental Berlin Chairs : Pascal Thubert Alexander Pelov Responsible AD : Suresh Krishnan URLs : http://tools.ietf.org/wg/lpwan https://datatracker.ietf.org/wg/lpwan/ https://www.ietf.org/mailman/listinfo/lpwan http://etherpad.tools.ietf.org:9000/p/notes-ietf-96-lpwan ``` * Intro and Status [5min] (Chairs) * Note-Well, Blue Sheets, Scribes, Agenda Bashing * General introduction, 6LPWA architecture (Alexander Pelov, P. Thubert) * Selected technologies: presentation and characterization [40mn] * Technology slot 1: 3GPP LPWA (NB-IoT / EC-GSM-IoT / Cat-M1) [10mn] (Antti Ratilainen) * Technology slot 2: IEEE LPWA (Wi-SUN, IEEE 802.15.4g) [10mn] (Bob Heile) * Technology slot 3: LoRa [10mn] (Alper Yegin) * Technology slot 4: SIGFOX [10mn] (Juan Carlos Zuniga) * Applicability and gap analysis of Internet protocols [20mn] * LPWA Gap analysis - Ana Minaburo (draft-minaburo-lp-wan-gap-analysis) * Analysis of IPv6 over LPWA: design space and challenges - Carles Gomez (draft-gomez-lpwan-ipv6-analysis) * Charter and work Items Discussions, led by chairs (< 1H) * Interaction model with LPWA technologies (just cross participations? ISGs?) * Review proposed work items, one by one Resources ========= * agenda: https://datatracker.ietf.org/meeting/96/agenda/lpwan * Links to audio streams, meetecho and jabber: https://tools.ietf.org/agenda/96/#96-mon-1540-lpwan * Presented slides: https://datatracker.ietf.org/meeting/96/session/lpwan/ Summary ======= Wg forming BoF lasted 2 hours. A generic architecture was presented by the BoF chairs, showing potential areas of work for the IETF. Short terms possible areas include compression all the way to CoAP, AAA, security, management. Longer term include a global architecture that includes overlay over the Internet for isolation, mobility, and addressing that does not leak into the DFZ. The 4 technologies considered, NB-IOT, 802.15.4 (Wi-SUN), LoRa and SIGFOX were introduced. The desire for common services and abstractions for the upper layers was clearly expressed, leading to the need for a place where that common abstraction is standardized based on IP. The gaps between existing IETF technologies (e.g. 6LoWPAN, ROHC) were exposed, with a focus on IPv6. The group was presented with a number of possible work items, and asked whether they understood the set of problems (consensus yes), where ready to work and review (both positive). Suresh polled for interest by end users from the technologies, high level of hum. The remaining question, raised by Erik, is whether a new WG is required. Suresh to work with the IESG to make that decision. Action items ============ Suresh to work with the IESG to decide whether a new WG is required. Volunteers ========== * Scribes * Dominique Barthel * Diego Dujovne * Jabber * Renzo Navas Minutes ======= * [15:46] Intro and Status [5min] (Chairs) * Note-Well, Blue Sheets, Scribes, Agenda Bashing * General introduction, LPWA architecture (Alexander Pelov, P. Thubert) * two sides of "low-power". RF transmission power as well as power drawn from battery (equating to lifetime on a primary battery). * radio link. Asymetric quality. Duty-cycling. * an array of constraints, not all reaching the extreme values in a given situation. Diverse cases * Typical architecture of this type of networks. As they exist today. * Challenges: Management of security. Maintain devices. Mobility (vehicles) Use addresses over overlays/security * Devices only wake up when they have something to transmit: LPWA devices. 6tisch for density and battery, with schedule. * Selected technologies: presentation and characterization [40mn] * Technology slot 1: 3GPP LPWA (NB-IoT / EC-GSM-IoT / Cat-M1) [10mn] (Antti Ratilainen) (Suresh standing in for him) * developped at 3GPP. 3GPP distinguishes Massive MTC and Critical MTC (Machine TYpe Communication). * this is for the low end of MMTC. * use licensed band from already deployed networks instead of unlicensed bands such as sigfox * three operation modes: use one gsm band, use the guard band (whitespace) in band using LTE band * receeiver sensibility -141dBm, provides long range. QPSK, 180 kHz badwidth. * Packet data convergence protocol (PDCP) right below IP. 1600 bytes. Use all the already existing mechanisms (NAS: Non acces stratum and AS: Access Stratum) * Mutual authentication. Shared secrets on the user. * Network architecture is based on ePC (evolved Packet Core). * * Questions: Sri: ? what are your expectations from this BOF? Suresh: presenting for Antti. Consider NB-IoT as one of the LPWAN techs and work on common solutions. As an AD, ... * Specifications for NB-IoT? Suresh :3GPP members get the documents. Maybe through a liaison. * Lionel Morand: released specs are available on the 3GPP web site. * Don Sturek: 3GPP release 14. * Suresh: there's a draft, go and read it and ask Antti if you have questions. * [16:07] Technology slot 2: IEEE LPWA (Wi-SUN, IEEE 802.15.4g) [10mn] (Bob Heile) * 15.4 is much wider range of tehcnologies than LPWAN * IETF and IEEE802 have been collaborating for years. * issues in 15.4a, k and g that are similar to other technologies described in this BOF. * Wi-SUN Alliance: profiles out of IEEE stnadards and few others. Does not develop standards. * Support and testing verification programs * Field Area Network profile (FAN). A profile for TEPCO (Japan) called Route B. Home Area Networking profile. * why Wi-SUN here today? serves the LPWAN space. Here for awareness, contributing experiencem ensure consistency, ... * Wi-SUN already uses IP, can interconnect to WiFi. * SRI: Specifical technical requirements? same as other presentation in this session. * Subir Das: 802.15.4 belongs to 6lo 15.12 to LPWA * Don Sturek: * [16:16] Technology slot 3: LoRa [10mn] (Alper Yegin) * * Long Range, Sub-GHz, Unlicensed. 300bps-50Kbps. Beyond 10Km. Payload: 11bytes-242 bytes. 10 yrs operation, supports unicast/multicast. Adaptive data rate to use network at maximum capacity. Supports mobility. * Data rate higher, closer to the source. * Dynamic negotiation with the network to adapt the data rate and the power. * 3 classes of operation: class A devices only receive just after they transit. Class B devices have scheduled reception. Class C is mains powered, has receiver on most of the time * Radio base-stations called Radio Gateways in LoRa parlance. MAC layer is called LoRaWAN, 1.0 version freely available from Alliance website * MAC address is 32bit, device id is 64bits. * Release 1.1 will have: backend interface (network,authentication, application servers), App and Session key separation, roaming. * various applications running on top of MAC layer. We dont have a way to use? coap and ipv6 * AES-CMAC data origin authentication, integrity protection, replay protection * can roll keys through re-join * Alliance: standardization and specification and foster ecosystem. 16 nationwide deployments 56 on-going trials * Don Sturek: Envision end device to Network server communication be in scope for IETF? * Alper: No. LoRaWAN is MAC layer, I dont think IETF should work on MAC layer. Would you help the IEEE to distill the requirements. We have a plan and write a draft. * Samita: constrained devices at 6lo, .. Alper: we feel that the LoRa constraints go beyond those that were considered at 6lo so far. * Pascal: some issues raised at LPWAN could be transfered to 6lo to profile technical solutions to them, much as has happened between 6TiSCH and 6lo. * [16:30] Technology slot 4: SIGFOX [10mn] (Juan Carlos Zuniga) * SIGFOX is an IoT service provider, not just technology provider. * will talk about technology here. * single core network even for radio gateways in multiple countries, no roaming. * asynchronous transmission, similar to Class A in LoRa. * "un-balanced" link, radio gateway has duty-cycle restriction and deals with many devices, so very restricted downlink communication compared to uplink. * optimized for uplink communications * no fragmentation, no encryption * applications... * expected battery lietime 10-15 years. * Sri: Open protocols between device and gateways? Device-Function interaction * On the draft is inclued only the items related to what is needed in IETF. Could add more on request. * architecture doc at ETSI. * Don Sturek: mobility? * Nomadic. Devices to move on any country. * xxx: authentication? What kind of credentials. JCZ: keys are pre-provisionned, no EAP. * Gabriel Montenegro: unlicensed spectrum. What about co-existence? JCZ: regulatory requirement on power and duty-cycle. * Different requirements as they are for wifi. Regulatory rules. Comply with them. * Wifi against LTE-LAA * Benoit Ponsard (Sigfox): EN300-200 in EU and FCC Part 15 in US. * Patrick Wettervald: Service provider? No mobility. Service provider ID? * Cloud provider for added value. * PW:Through SigFox company to transmit? Yes, only one network worldwide. * Yes. * [16:45] Applicability and gap analysis of Internet protocols [20mn] * LPWA Gap analysis - Ana Minaburo (draft-minaburo-lp-wan-gap-analysis) * objective to discuss how the current WG at IETF could tackle some of the problems, and what should be done in an LPWAN group. * goes through LPWAN characteristics again. Key characteristic is "bytes per day", not per second. * architecture overview, similar for different technologies but for the names given to the various functions. Will need to agree on terminology. * will re-use current protocols. Some IPv6 issue: header overhead, variable MTU yields variable number of frames for same IP packet. * current WGs related to this space: 6lo, ROHC, 6TiSCH, Core, ... * 6lowpan different from LPWA because of the distributed nature of these networks and unidirectional links * RoHC too complex in the original version to address this problem * Adapt synchronization from 6TiSCH to LPWAN * Adapt the COAP solution for the Duty cycle length. * We have to find out a place where to put all these solutions together to find what is missing? * Gabriel: did you say 6LoWPAN header 6 bytes? Ana: yes IPv6 and UDP. * Luca Martini: on slide ??, "reachability", what do you mean? * to be able to deploy the device wherever we like. * []? * use overlays to isolate the devices but keep communication with their cluod? * Vince Park (?) (Ben Sparks): clarifying question. You said "no ACK", you mean "in some technologies"? Ana: indeed. * Pascal: This is specific for this technology unlike 802.15.4 that already has 6lowpan. * Lionel Morand: you mentioned strong security of IP but did not mention IETF working groups contributing on security to this work. * Ana: Use what was already done and adapt it. Doesn't seem like new work is needed on security, but we'll see. Pascal: ... ANIMA... * Geoff Mulligan: this is a list of gaps, the ga analysis is not done. Ana: indeed. * Suresh: my advice is find what is needed, not jump to solutions. * Alex: Ana's draft is only 13 pages, read and comment. * [17:02] Analysis of IPv6 over LPWA: design space and challenges - Carles Gomez (draft-gomez-lpwan-ipv6-analysis) * traditionally 6LoWPAN used to adapt IPv6 to constrained networks, now even more constrained networks, sometime by orders of magnitude. * LPWAN is a real challenge for 6LoWPAN. * this draft has challenges and guidelines * challenges: .. device ID privacy, fragmentation, neighbor discovery, header compression * see slides for more detail on these challenges ;-) * Eric Vyncke (Cisco) router advertisement... really needed? * Yes. * Zach Shelby: careful. Not try to apply all IP technologies on any radio technology? If it doesn't fit, why force it... Star networks mostly, don't need a lot of stuff. Most of what you're trying to do has already been done at 6lo, size your WG ambition. * Gabriel Montenegro: what is it that you need. 6LoWPAN was for 15.4, 15.4 has shared state. These networks seem to have even more shared state, make use of it. * Gabriel: privacy addressing. Should say "All devices should be mindful of privacy, see document at 6lo on this topic". * Suresh: work that should be done at 6lo will be done at 6lo. Lower layer components may no happen here. This WG would be about "solution". * Ben Sparks: Does this make sense? Gap Analysis: if the link layer is so constrained to support IP traffic, a higher layer should do the job. * Pascal: need for an architecture. Which component/functionality goes where. Is new model/topology needed? * Suresh: we need to move on. * Matias Kovatsch: not much work what can we expect from these networks. Common expectation from the Alliances for the work that could be done here. * Suresh: Charter discussion covers this. * [17:20] Charter and work Items Discussions, led by chairs (< 1H) * Interaction model with LPWA technologies (just cross participations? ISGs?) * Review proposed work items, one by one * Pascal: list of potential work items, does any pertain to IETF? please humm * Suresh: First, is it clear to the people on the room which is the problem to be solved are? * list is: compression, fragmentation security, mobility, scheduling, management, signaling, RESTful enablement, architecture to tie everything together * Suresh: Common understanding of the set of problems? * Pascal: Those who understand, please humm? significant humm * Pascal: Those who do not understand please humm? silent. * Renzo: Jabber: 3 hums for yes / 0 for no * Margaret (Wasserman) (Cullen): full list of mixed items, response could differ per item. * Do these kind of features match those of the IETF? * Juan Carlos: The list of issues does not necessarily match to the charter. Maybe other groups or outside the IETF. * Pascal: have a place to put things together, and request/push work from/to other WGs, much like we did in 6TiSCH. * who is on the mailing list: majority of the audience in the room * Charter points 1 displayed on screen. * Pascal: This is the summary of the whole presentation. * Pat Kinney (Jabber): IEEE 802.15.12 is considering working on device and radio resource management for 802.15.4. Response from Suresh: Yes simmilar point to Juan Carlos * Charter points 2 on screen: gap analysis. Alper: per technology? * Pascal: will be a WG doc, WG will decide, but my intention is no finger-pointing. * Suresh: small change in proposed charter to say what is technology-specific and what is not. * Charter points 3 put on screen. Standard Track document on compression. * Zach: this is "let's invent a new compression mechanism". Pascal: yes. Zach: why? Pascal: best of both 6LoWPAN and ROHC. Compress the way RoHC does. * Zach: 6lowpan already elides ipv6 and udp in most cases. You want to go further takig advantage of the larger shared context, as Gabriel said. * Geoff Mulligan: what does "over LPWA" mean? * Pascal: not enforcing to see IP on the LPWA link. Enabled but not enforced. The real stack is on the gateway. * Charter points 4 put on screen. Fragmentation * Margaret: is it well-defined which LPWA technologies are being considered? Pascal: called out and 4 technology providers came forward * Margaret: IP-over-foo. Do one after the other and re-use previous one to do the next. Haven't seen IP-over-foo in this meeting * Suresh: IPv6-over-foo belongs in 6lo. This is about something more, we have a more restricted environment: few packets, very small packets Pascal: putting IETF "components" together to deliver a package to users. * Suresh: 3GPP is already doing IP over some of their technologies. They come to us for the higher layers, * Pascal: overlays, AAA, provide IETF components that they need. * Samita: charter based on some drafts discussed at this mmeeting. But given 4 different technologies, would like to see new requirements not already addressed at IETF today. Pascal: this is point 2. Point 3 already delivers something so that users don't wait for us to figure the requirements. * Samita: should focus on the requirements. * Sri: * Pascal: we'll discuss it on the mailing list. No immediate answer anyway * Suresh: feeing for understanding of the proposed charter. How many people understand. Those who have questions, please humm. None * Suresh: enough work for the IETF to do, humm: significant humm. (jabber, hum yes 1 . no: 0) * Suresh: those who ..., please humm. One heard (Erik) * Erik Nordmark: work to be done, but should this mean form a new WG? * Margaret: Are there more items? * Suresh: who is interested in contributing to the lpwan? big humm * Suresh: interested in reviewing? significant humm (jabber: 3 hums) * interested in using is something comes out. Fairly significant humm (jabber: 2 humms) * Lionel: clarify what you would like to do. Compression seems clear. Security lessa clear. * Suresh: got the answers that wanted out of this meeting.