idnits 2.17.1 draft-sjkoh-requirements-iot-vlc-00.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year == The document seems to lack the recommended RFC 2119 boilerplate, even if it appears to use RFC 2119 keywords -- however, there's a paragraph with a matching beginning. Boilerplate error? (The document does seem to have the reference to RFC 2119 which the ID-Checklist requires). -- The document date (4 November 2019) is 1632 days in the past. Is this intentional? -- Found something which looks like a code comment -- if you have code sections in the document, please surround them with '' and '' lines. Checking references for intended status: Informational ---------------------------------------------------------------------------- No issues found here. Summary: 0 errors (**), 0 flaws (~~), 2 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Internet-Draft Seok J. Koh 3 Intended status: Informational Cheol M. Kim 4 Expires: 7 May 2020 Kyungpook National University 5 4 November 2019 7 Requirements for IoT Services based on Visible Light Communications 8 draft-sjkoh-requirements-iot-vlc-00 10 Abstract 12 This document describes the requirements for IoT Services based on 13 Visible Light Communication (VLC) to effectively provide IoT services 14 in the VLC-based networks. This document includes the overview of 15 VLC technology and the concepts of VLC-based IoT services, and the 16 requirements for IoT services in the VLC-based networks. 18 Status of This Memo 20 This Internet-Draft is submitted in full conformance with the 21 provisions of BCP 78 and BCP 79. 23 Internet-Drafts are working documents of the Internet Engineering 24 Task Force (IETF). Note that other groups may also distribute 25 working documents as Internet-Drafts. The list of current Internet- 26 Drafts is at https://datatracker.ietf.org/drafts/current/. 28 Internet-Drafts are draft documents valid for a maximum of six months 29 and may be updated, replaced, or obsoleted by other documents at any 30 time. It is inappropriate to use Internet-Drafts as reference 31 material or to cite them other than as "work in progress." 33 This Internet-Draft will expire on 7 May 2020. 35 Copyright Notice 37 Copyright (c) 2019 IETF Trust and the persons identified as the 38 document authors. All rights reserved. 40 This document is subject to BCP 78 and the IETF Trust's Legal 41 Provisions Relating to IETF Documents (https://trustee.ietf.org/ 42 license-info) in effect on the date of publication of this document. 43 Please review these documents carefully, as they describe your rights 44 and restrictions with respect to this document. 46 Table of Contents 48 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 49 1.1. Terminology and Requirements Language . . . . . . . . . . 2 50 2. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 3 51 2.1. Visible Light Communication . . . . . . . . . . . . . . . 3 52 2.2. IoT services based on VLC . . . . . . . . . . . . . . . . 4 53 2.3. Network nodes . . . . . . . . . . . . . . . . . . . . . . 6 54 2.3.1. IoT Server (IS) . . . . . . . . . . . . . . . . . . . 6 55 2.3.2. VLC Agent (VA) . . . . . . . . . . . . . . . . . . . 6 56 2.3.3. VLC Light (VL) . . . . . . . . . . . . . . . . . . . 6 57 2.3.4. User Terminal (UT) . . . . . . . . . . . . . . . . . 6 58 3. Requirements for IoT services based on VLC . . . . . . . . . 7 59 3.1. Device initialization . . . . . . . . . . . . . . . . . . 7 60 3.2. Device monitoring . . . . . . . . . . . . . . . . . . . . 7 61 3.3. Uplink channel for UT in the uni-directional VLC . . . . 7 62 3.4. Data transport . . . . . . . . . . . . . . . . . . . . . 8 63 3.5. Light control . . . . . . . . . . . . . . . . . . . . . . 8 64 3.6. Device roaming . . . . . . . . . . . . . . . . . . . . . 8 65 4. Security consideration . . . . . . . . . . . . . . . . . . . 9 66 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 67 6. Normative References . . . . . . . . . . . . . . . . . . . . 9 68 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 70 1. Introduction 72 The VLC has been developed as a wireless communication technology 73 which uses visible lights, infrared (IR), and ultra-violet (UV) 74 spectrum instead of conventional RF band. In particular, the VLC 75 provides the following distinctive features: 1) non-interference to 76 existing RF bands, 2) free license to use the spectrum of visible 77 light, IR, and UV, and 3) VLC can be easily deployed with the 78 existing LED lights. Since the VLC is non-RF based wireless 79 communication technology, it can be complementary wireless 80 communication technology among the RF-based wireless communication 81 technologies (mobile network, WPAN, WLAN). These distinctive 82 features of VLC will be helpful to overcome the shortcomings of the 83 existing RF technologies. 85 1.1. Terminology and Requirements Language 87 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 88 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 89 "OPTIONAL" in this document are to be interpreted as described in BCP 90 14. [RFC2119], [RFC8174] when, and only when, they appear in all 91 capitals, as shown here. 93 2. Overview 95 2.1. Visible Light Communication 97 The Visible Light Communication (VLC) technology has been developed 98 to transmit data through the license-free spectrum of visible light, 99 IR, and UV. [ITU-T_G.9991] [IEEE_802.15.7-2018] Data is encapsulated 100 into VLC frames, and it is coded using digital-based modulation 101 technology, such as Pulse Width Modulation (PWM), Orthogonal 102 Frequency Division Multiplexing (OFDM), and so on. Those coded VLC 103 frames are transmitted by LED or Laser Diode (LD). A Photo Diode 104 (PD) or an image sensor can receive the VLC frames. 106 The [ITU-T_G.9991] specifies the system architecture, PHY and data 107 link layer of high-speed indoor VLC transceiver, especially for home 108 network. The [ITU-T_G.9991] network comprises on or more domains. 109 Each domain has one domain master and one or more nodes which are 110 registered to the domain master. Global Master (GM) is responsible 111 to coordinate the resources among domains. 113 For each domain, the [ITU-T_G.9991] specifies the five topologies for 114 indoor VLC: peer to peer (or point to point) topology (P2P), point to 115 multipoint topology (P2MP), multipoint to multipoint (MP2MP), relayed 116 mode, and centralized topology. In addition to network topology, the 117 .[ITU-T_G.9991] specifies the modes of operation in a domain, which 118 includes centralized mode (CM) and unified mode (UM). In centralized 119 mode, the direct communication between domain master (DM) and end- 120 point node (EP) is allowed, while direct communication among end- 121 point nodes are note allowed. The CM supports 3 types of operation 122 mode: a) bi-directional communication, b) broadcast only, and c) 123 hybrid communication. In the unified mode, the direct or indirect 124 communication among nodes is allowed. 126 The [IEEE_802.15.7-2018] specifies PHY and MAC sublayer for VLC. In 127 [IEEE_802.15.7-2018], it uses the term Optical Wireless 128 Communications (OWC) rather than VLC because the standard explicitly 129 considers the wavelength from 10,000nm to 190nm, which includes 130 visible light, IR, and UV. Also, the standard introduces the term 131 Optical Wireless Personal Area Network (OWPAN) with specifying 132 network topology, addressing, collision avoidance, acknowledgement, 133 performance quality indication, dimming support, visibility support, 134 colored status indication, and color stabilization. 136 In [IEEE_802.15.7-2018], it classifies three types of devices in OWC: 137 infrastructure, mobile, and vehicle. Table 1 shows the 138 classification of devices. 140 +-------------------+----------------+-------------+---------------+ 141 | Features | Infrastructure | Mobile | Vehicle | 142 +===================+================+=============+===============+ 143 | Fixed coordinator | Yes | No | No | 144 +-------------------+----------------+-------------+---------------+ 145 | Power supply | Ample | Limited | Moderate | 146 +-------------------+----------------+-------------+---------------+ 147 | Form factor | Unconstrained | Constrained | Unconstrained | 148 +-------------------+----------------+-------------+---------------+ 149 | Light Source | Intense | Weak | Intense | 150 +-------------------+----------------+-------------+---------------+ 151 | Physical mobility | No | Yes | Yes | 152 +-------------------+----------------+-------------+---------------+ 153 | Range | Short/long | Short | Long | 154 +-------------------+----------------+-------------+---------------+ 155 | Data rates | High/low | High | Low | 156 +-------------------+----------------+-------------+---------------+ 158 Table 1: Device classification in [IEEE_802.15.7-2018] 160 The [IEEE_802.15.7-2018] specifies three network topologies: peer-to- 161 peer, star, and broadcast. A one device gets a role of coordinator, 162 which is determined by applications. The standard specifies the 163 visibility support across all topologies with flicker mitigation. 165 2.2. IoT services based on VLC 167 This document describes the concept of IoT services based on VLC. 168 The goal of VLC-based IoT services is the functionality as follows: 170 * Device initialization, including device discovery and device 171 registration. 173 * Data transport using VLC for downlink channel from lighting device 174 to user terminal. 176 * Data transport using VLC for uplink from user terminal to lighting 177 devices or using other RFs for uplink channel from user terminal 178 to the VLC agent device. 180 * Light control, such as the configuration of dimming, color, 181 modulation of visible lights. 183 * Device monitoring. 185 * Roaming support for mobile user terminal. 187 Figure 2 and 3 shows the network model for VLC-based IoT services, 188 which uses bi-directional VLC environment and uni-directional VLC 189 environment. Also, those figures describe the network nodes in the 190 VLC-based IoT network: IoT server (IS), VLC Agent (VA), VLC Light 191 (VL), and User Terminal (UT). 193 +----+ Ethernet +----+ Ethernet/WLAN/WPAN +-----------+ 194 | IS |<========>| VA |<==================>| VTs | 195 +----+ +----+ |(LED Light)| 196 +-----------+ 197 * * 198 * Data * 199 * through VLC * 200 * (Visible light, * 201 * IR, UV) * 202 * * 203 ^ 204 +------------+ bi-directional VLC * 205 | UT | (VT <-> UT) * 206 |(IoT Device)|<********************* 207 +------------+ 209 Figure 1: VLC-based IoT services in bi-directional VLC environment 211 +----+ Ethernet +----+ Ethernet/WLAN/WPAN +-----------+ 212 | IS |<========>| VA |<==================>| VTs | 213 +----+ +----+ |(LED Light)| 214 ## +-----------+ 215 ## * * 216 ## Uplink channel * Data * 217 ## for UT * through VLC * 218 ## (WLAN/WPAN) * (Visible light, * 219 ## * IR, UV) * 220 ## * * 221 ## * 222 +------------+ uni-directional VLC * 223 | UT | (downlink channel, VT -> UT) * 224 |(IoT Device)|<****************************** 225 +------------+ 227 Figure 2: VLC-based IoT services in uni-directional VLC environment 229 As shown in Figure 2 and 3, it is noted that there two kinds of VLC 230 between UT and VL/VA: uni-directional VLC and bi-directional VLC. In 231 the bi-directional VLC case, VLC is performed between UL and VL. 232 That is, both the downlink from VL to UT and the uplink from UT to VL 233 use the VLC. However, in the uni-directional VLC case, only the 234 downlink uses the VLC, whereas the uplink may use the other OF 235 technologies, such as WLAN or WPAN. In the viewpoint of VLC 236 deployment in real-world networks, the bi-directional VLC is 237 suggested, but the uni-directional VLC may ne used in a certain 238 network. 240 For VLC-based IoT networks, we consider the following four types of 241 network nodes: Platform Server (PS), Aggregation Agent (AA), VLC 242 Transmitter (VT), and VLC Receiver (VR). Figure 1 shows uni- 243 directional VLC from VT to VR, in which only downlink VLC 244 transmission is allowed from VT to VR, and the uplink or backward 245 transmission will be made between VR and AA by using another network 246 link, such as WLAN or WPAN. 248 2.3. Network nodes 250 2.3.1. IoT Server (IS) 252 IS is responsible for overall management for all devices in VLC-based 253 IoT network. IS performs IP-based protocol operations including the 254 device initialization, device registration, device monitoring, light 255 control, and device roaming. In addition, IS transmits data to VL 256 and UT in the data transport operation. IS is connected to the 257 Internet. 259 2.3.2. VLC Agent (VA) 261 For effective management of VLC-based IoT services, one or more VAs 262 can be deployed in the network. VA is purposed to perform IP-based 263 protocol operations and to locally manage its associated VLs and UTs. 264 It keeps an association information between VL and UT, and such 265 information may be updated in the device monitoring and device 266 roaming operations. VA has a responsibility to relay data between IS 267 and VL/UT. 269 2.3.3. VLC Light (VL) 271 VL can be installed or embedded on an LED light. In the 272 initialization, VL is registered to IS. After that, VL advertises 273 itself to user terminals in the VLC network by using VLC. VL has a 274 responsibility to translate IP-based data to VLC frames and vice 275 versa. 277 2.3.4. User Terminal (UT) 279 UT represents a user device with the VLC functionality. All UTs can 280 be registered to and managed by IS via its associated VL and/or VA in 281 the device initialization and monitoring operations. VLC data are 282 also exchanged between UT and IS by way of VL and/or VA. 284 3. Requirements for IoT services based on VLC 286 3.1. Device initialization 288 To enable IoT services based on VLC, all devices need to find uplink 289 device, join the network, and make them discoverable in the network. 290 The followings are the requirements for device initialization: 292 * All devices MUST have capabilities of device advertisement and 293 device discovery in VLC-based IoT network. 295 * Each device MUST generate its unique ID (Identifier) and make 296 association to its uplink device. 298 3.2. Device monitoring 300 IS manages all VA, VL, and UT in the network via monitoring 301 operations. The followings are the requirements for device 302 monitoring: 304 * Each device MUST generate its status information. 306 * Each device MUST send its status information to its uplink device 307 periodically. 309 * Each device MUST receive the request of status information from 310 its uplink device and MUST send its up-to-date status information 311 to the uplink device. 313 3.3. Uplink channel for UT in the uni-directional VLC 315 In uni-directional VLC environment, the UT, which only has capability 316 of downlink VLC, needs an uplink channel for enabling IoT services. 317 The followings are the requirements for uplink channel management: 319 * VA MUST create RF based uplink channel for uplink channel in the 320 uni-directional VLC case. 322 * VA MUST configure RF based uplink channel with the parameters 323 received from its uplink device. 325 * VA MUST send the information of RF based uplink channel to 326 downlink device. 328 * VA MUST forward data packets to uplink and downlink channel. 330 * VL MUST generate a VLC frame which includes the information of RF 331 based uplink channel and to send the VLC frame to downlink device 332 periodically. 334 * UT MUST receive a VLC frame from uplink device and to extract the 335 information of RF based uplink channel. 337 * UT MUST establish the uplink channel with VA when UT has the uni- 338 directional VLC. 340 3.4. Data transport 342 In VLC-based IoT services, IP-based and VLC frame-based data need to 343 interoperate in all devices. The followings are the requirements for 344 data transport: 346 * All devices MUST handle IP-based data packets in VLC-based IoT 347 network. 349 * VL and UT MUST translate IP-based data packet to VLC frames, and 350 vice versa. 352 3.5. Light control 354 IS controls all VL by configuring the parameters associated with LED 355 lights. The followings are the requirements for light control: 357 * VL MUST handle the request of IS for configuration of LED light. 359 * VL MUST change the physical characteristics of LED light, as per 360 the request of IS. 362 3.6. Device roaming 364 When UT is mobile device, the IoT services need to be continued, even 365 though UT changes its attached VL. The followings are the 366 requirements for device roaming: 368 * UT MUST discover the neighboring VLs in the roaming case. 370 * UT MUST generate and exchange the roaming data with its 371 neighboring VL. 373 * VL MUST detect the roaming event from the association request with 374 the roaming data. 376 * VL MUST notify the roaming event to uplink VA device. 378 * IS and VL MUST handle the roaming request appropriately. 380 4. Security consideration 382 TBD 384 5. IANA Considerations 386 TBD 388 6. Normative References 390 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 391 Requirement Levels", BCP 14, RFC 2119, 392 DOI 10.17487/RFC2119, March 1997, 393 . 395 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 396 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 397 May 2017, . 399 [ITU-T_G.9991] 400 International Telecommunications Union, "High-speed indoor 401 visible light communication transceiver - System 402 architecture, physical layer and data link layer 403 specification", March 2019. 405 [IEEE_802.15.7-2018] 406 IEEE, "802.15.7-2018 - IEEE Standard for Local and 407 metropolitan area networks--Part 15.7: Short-Range Optical 408 Wireless Communications", 23 April 2019, 409 . 412 Authors' Addresses 414 Seok-Joo Koh 415 Kyungpook National University 416 Daehakro 80, Bukgu, Daegu, South Korea 41566 418 Phone: +82 53 950 7356 419 Email: sjkoh@knu.ac.kr 421 Cheol-Min Kim 422 Kyungpook National University 423 Daehakro 80, Bukgu, Daegu, South Korea 41566 425 Email: cheolminkim@vanilet.pe.kr