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LPWAの仕組みとセキュリティ

chibiegg
April 27, 2017

 LPWAの仕組みとセキュリティ

#ssmjp 2017/04/27

chibiegg

April 27, 2017
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  1. লిྗ޲͚-5&  3BUF6% %VQMFY %39 උߟ $BU .CQT શೋॏ TFD

    ݱߦ $BU .CQT શೋॏ൒ೋॏ TFD .*.0ͳ͠ $BU. .CQT શೋॏ൒ೋॏ NJO /#*P5 LCQT ൒ೋॏ IPVS ϋϯυΦʔόʔͳ͠
  2. αϒΪΨڞ௨ͷϧʔϧ  ARIB STD-T108 920MHz-BAND TELEMETER, TELECONTROL AND DATA TRANSMISSION

    RADIO EQUIPMENT IUUQXXXBSJCPSKQFOHMJTIIUNMPWFSWJFXEPD45%5W@&QEG
  3. ૹ৴ʹؔ͢Δ੍ݶ "3*#45%5ΑΓൈਮ  Sending control, 3.4.2 Carrier sense and 3.4.3

    Skipping carrier sense in a response. Table 3-18 Possible combinations of sending control parameters specified by 3.4.1 Sending control, 3.4.2 Carrier sense and 3.4.3 Skipping carrier sense in a response Conditions of response to skip carrier sense (Note 4) Antenna power Applied CH number Unit CH bandwidth CH used in a bundle Carrier sense time Sending duration Pause duration The sum of emission time per arbitrary one hour Completion time Start time 1-5 200kHz 1~5ch 100ms or less(Note2) 100ms 3.6sec or less ― ― 1mW or less 62-77 100kHz 1~5ch None 50ms or less(Note3) 50ms None ― ― 24-38 200kHz 1~5ch 5ms or more 4s(Note1) 50ms None ― ― More than 200ms, and 400ms or less Ten times or more of the former sending time More than 6ms, and 200ms or less 2ms 1ch 6ms or less None 50ms or less More than 3ms, and 200ms or less 2ms 2ch 3ms or less None More than 2ms, and 100ms or less 2ms 20mW or less 33-61 200kHz 3~5ch 128μs or more 2ms or less None 360sec or less 5ms or less 2ms or less (Note1) It may emit again without waiting 50ms, if it is within 4s after its first emission. The
  4. 4*('09  IUUQXXXTPVNVHPKQNBJO@DPOUFOUQEG SIGFOX 無線特性 (上り信号) 無線アクセス制御 ランダム・アクセス 変調方式 シングルキャリア:

    SSB-SC + D-BPSK データレート 100bps 使用チャネル幅 200kHz シングルキャリア周波数帯幅 100Hz 送信電力 20mW以下 最大送信継続時間 2s 与干渉抑制技術 キャリアセンス時間:5ms (単位チャネル200kHzをキャリアセンス) Duty Cycle:最大1% 被干渉耐性技術 ・同一データ繰り返し送信(3回) ・サイトダイバーシチ ・チャネル干渉に対し高いSNIR特性 無線特性 3 その他特徴 長距離伝送:リンクバジェット158dB 周波数効率:1基地局あたり1日100万メッセージ受信 200kHz 100Hz #1 #1 #1 #2 #2 #2 #3 #3 #3 #4 #4 #4 周波数 時間 2s 200kHz 1ճ͋ͨΓ25όΠτ * ϔομ౳ؚΉ
 ϖΠϩʔυ͸όΠτ
  5. -P3B8"/ͷ࢓༷ΛݟͯΈΑ͏  IUUQTXXXMPSBBMMJBODFPSHQPSUBMTTQFDT-P3B8"/4QFDJpDBUJPO3QEG LoRaWAN Specification 1 2 LoRaWAN™ Specification 3

    4 Authors: 5 N. Sornin (Semtech), M. Luis (Semtech), T. Eirich (IBM), T. Kramp (IBM), 6 O.Hersent (Actility) 7 8 Version: V1.0 9 Date: 2015 January 10 Status: Released 11
  6. -P3B8"/ͷϨΠϠʔ  A LoRa network distinguishes between a basic LoRaWAN

    (named Class A) and optional 6 features (Class B, Class C …): 7 Application LoRa MAC LoRa Modulation EU 868 EU 433 US 915 AS 430 … Class B (beacon) Class C (Continuous) Application MAC MAC options Modulation Regional ISM band Class A (baseline) 8 Figure 1: LoRaWAN Classes 9
  7. ௨৴଎౓  868.30 868.50 Table 13: EU863-870 JoinReq Channel List

    15 7.1.3 EU863-870 Data Rate and End-point Output Power encoding 16 The following encoding is used for Data Rate (DR) and End-point Output Power (TXPower) 17 in the EU863-870 band: 18 DataRate Configuration Indicative physical bit rate [bit/s] TXPower Configuration 0 LoRa: SF12 / 125 kHz 250 0 20 dBm (if supported) 1 LoRa: SF11 / 125 kHz 440 1 14 dBm 2 LoRa: SF10 / 125 kHz 980 2 11 dBm 3 LoRa: SF9 / 125 kHz 1760 3 8 dBm 4 LoRa: SF8 / 125 kHz 3125 4 5 dBm 5 LoRa: SF7 / 125 kHz 5470 5 2 dBm 6 LoRa: SF7 / 250 kHz 11000 6..15 RFU 7 FSK: 50 kbps 50000 8..15 RFU Table 14: Data rate and TX power table 19 7.1.4 EU863-870 JoinAccept CFList 20
  8. -P3B8"/ͷΫϥε  Class A (baseline)
 ɹશͯͷΤϯυσόΠεʹద༻ɺMACΛؚΉ Class B (beacon) 


    ɹClassAʹՃ͑ɺఆظతͳड৴ Class C (continuous)
 ɹClassAʹՃ͑ͯɺৗʹड৴͢ΔΤϯυσόΠε
  9. ௨ৗ࣌ͷૹ৴λΠϛϯά  ©2015 LoRa™ Alliance Page 74 of 82 The

    authors reserve the right to change specifications without notice. empty data message to open additional receive windows at its own discretion, or wait until it 22 has some data to transmit itself and open receive windows as usual. 23 Note: The FPending bit is independent to the acknowledgment 24 scheme. 25 26 gateway End-point Data uplink {cu} Confirmed Data0+F_P {cd} ACK {cu+1} Confirmed Data1 {cd+1} ACK {cu+2} ok ok ok (*) F_P means ‗frame pending‘ bit set Receive slots LoRaWAN Specification Figure 17: Downlink timing diagram for frame-pending messages, example 1 1 In this example the network has two confirmed data frames to transmit to the end-device. 2 The frame exchange is initiated by the end-device via a normal ―unconfirmed‖ uplink 3
  10. ଛࣦ͕ൃੜͨ͠৔߹ͷૹ৴λΠϛϯά  Note: An acknowledgement is never sent twice. 18

    The FPending bit, the ACK bit, and payload data can all be present in the same downlink. 19 For example, the following frame exchange is perfectly valid. 20 21 22 Figure 19: Downlink timing diagram for frame-pending messages, example 3 23 The end-device sends a ―confirmed data‖ uplink. The network can answer with a confirmed 24 downlink containing Data + ACK + ―Frame pending‖ then the exchange continues as 25 previously described. 26 gateway End-point Confirmed Data uplink {cu} Confirmed Data0+F_P+ACK {cd} ACK {cu+1} Confirmed Data1+F_P {cd+1} ACK {cu+3} ok void {cu+2} Receiving a frame without the ACK bit set , server retransmits Data1 ok ok Confirmed Data1+F_P {cd+1} (diag 2)
  11. ."$૚  All LoRa uplink and downlink messages carry a

    PHY payload (Payload) starting with a 2 single-octet MAC header (MHDR), followed by a MAC payload (MACPayload)1, and ending 3 with a 4-octet message integrity code (MIC). 4 5 Radio PHY layer: 6 Preamble PHDR PHDR_CRC PHYPayload CRC* Figure 5: Radio PHY structure (CRC* is only available on uplink messages) 7 PHYPayload: 8 MHDR MACPayload MIC Figure 6: PHY payload structure 9 MACPayload: 10 FHDR FPort FRMPayload Figure 7: MAC payload structure 11 FHDR: 12 DevAddr FCtrl FCnt FOpts Figure 8: Frame header structure 13 Figure 9: LoRa message format elements 14 σʔλຊମ
 ҉߸Խର৅ HMAC
  12. ࣗݾ঺հ  @DIJCJFHH ʲॴଐʳ ͘͞ΒΠϯλʔωοτגࣜձࣾ
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    •͘͞ΒͷVPS API/DB/੍ޚγεςϜ୲౰ •sakura.io ઃܭɾ։ൃ ιϑτ΢ΤΞ/Πϯϑϥ/૊ΈࠐΈΤϯδχΞ