1. doc.: IEEE 802.15-16-0238-00 Submission March 2016 Willem Mulder, Dialog SemiconductorSlide 1 EC Monday Meeting Report March 14, 2016 Venetian Macau Hotel and Casino Macau, China

2. doc.: IEEE 802.15-16-0238-00 SubmissionWillem Mulder, Dialog Semiconductor2 Proposal for an adaptive throughput/link- budget mode in the 802.15.4 PHY March 2016

3. doc.: IEEE 802.15-16-0238-00 Submission IoT in the Smart Home Willem Mulder, Dialog Semiconductor3 Smart Home connectivity in the ISM band. “Best Effort” connectivity. Proven technology, it works great. Safety sensors (Fire/CarbonMonoxide) => single bit messages, extreme reliability requirements Security sensors => single bit messages, extreme reliability requirements Door-locks => single bit messages, extreme reliability requirements For some use cases, “Best Effort” is not enough Can we ignore these use cases ? We think not.. Why don’t we use adaptive throughput/link-budget allocation like WiFi,UMTS,LTE ? March 2016

4. doc.: IEEE 802.15-16-0238-00 Submission 802.15.4 Sensor Network Topology Willem Mulder, Dialog Semiconductor4 Network Device (Sleepy End Device) FFD Coordinator (Border Router) FFD Coordinator (Router) Network Device (Powered End Device) FFD PAN Coordinator (Leader) SED link Wifi link Router–Router link A global IPv6-enabled mesh network example Fixed 250 kbps throughput, fixed link-budget What holds us from trading throughput for link-budget ? Shannon: March 2016

5. doc.: IEEE 802.15-16-0238-00 Submission The 802.15.4 PHY Willem Mulder, Dialog Semiconductor5 PHY Packet Fields Preamble (32 bits) – synchronization Start of Packet Delimiter (8 bits) PHY Header (8 bits) – PSDU length PSDU (0 to 1016 bits) – Data field PSDUPreambleSPD PHD R 8 bits32 bits 0 – 1016 bits (127 bytes) 8 bits 32 us128 us0 – 4.064 ms32 us 12 symbols 0 – 254 symbols 1 symbol = 16us = 0.5 byte (octet) PHY Payload: max 127 bytes PHY packet duration: max 4.256 ms March 2016

6. doc.: IEEE 802.15-16-0238-00 Submission How do we use the payload ? Willem Mulder, Dialog Semiconductor6 1.. 4 ms (64/63 bytes overhead/payload with DTLS, 35/92 bytes overhead/payload without DTLS) 6LoWPAN enabled Data-transfer packet 802.15.4 Data-poll packet 768 us (24 bytes), native 802.15.4 MAC packet Authentication Security Routing Medium Access What holds us from scaling down the throughput ? March 2016

7. doc.: IEEE 802.15-16-0238-00 Submission 802.15.4 Authentication and Security Willem Mulder, Dialog Semiconductor 7 Message Integrity Hash Encrypt Decrypt MAC Security Key Message Integrity Hash Compar e Transmit Side Receive Side AES-CCM32 16 Step 1: Message Authentication Step 2: Encryption March 2016

8. doc.: IEEE 802.15-16-0238-00 Submission The 802.15.4 PHY Trading throughput for link-budget: we already do it Willem Mulder, Dialog Semiconductor 8 T chip = 0.5 us, 32 chips/symbol T symbol = 16 us, 4 bits/symbol I Q Good Hamming Distance mean = 17 min = 12 max = 21 Excellent Autocorrelation … Each new symbol is created by a 4-chip right-shift (first 8 symbols), or by taking the complex conjugate (last 8 symbols), reducing correlator complexity (cost) => 2.5 dB coding gain => 9 dB processing gain => 250 kbps throughput March 2016

9. doc.: IEEE 802.15-16-0238-00 Submission The 802.15.4 PHY Willem Mulder, Dialog Semiconductor9 PSDUPreambleSPD PHD R 32 chips256 chips 0 – 8128 chips 32 chips 32 us128 us0 – 4.064 ms32 us 12 symbols 0 – 254 symbols Boundary conditions / Design considerations: 802.15.4 RF compatible (channel BW, chiprate, O-QPSK-sensitivity) 802.15.4 Receiver-conditioning compatible (Preamble, AGC,..) Flexible packet size/pn-code-length, max pn-code-length is 8128 chips Processing gain upper bound: 39.1 dB for a 1-bit message Coding gain: dependent on the chosen pn-code-bundle (Hamming distance) Security/Authentication: use pn-code-selection and pn-code-rotation Processing gain: energy-per-bit to energy-per-chip ratio in zero-mean AWGN channels Coding gain / Hamming distance: how many chips can go wrong before our detector chooses the wrong code What when we don’t need 127 bytes ? How scalable are we ? March 2016

10. doc.: IEEE 802.15-16-0238-00 Submission Corner Case: 1-bit Extreme Reliability Willem Mulder, Dialog Semiconductor10 Sleepy End Device Border Router Router Powered End Device Leader role SED link Wifi link Router–Router link Extreme Reliability Node 1 ER-Node commissioning using the regular protocol 2 ER-Node subscribes at multiple ER-capable Routers 3 ER-Node receives the security parameters 4 ER-Node sends the alert-action table to the Router 5 pn-code-bundle and pn-code-rotation agreed (security/authentication by code-selection) 6 ER-node switches to ER-mode-operation: send regular heartbeat-messages send alert-messages when needed Robustness: Mesh Diversity: Multiple ER receivers (Routers) Extended link budget (Processing Gain) Multiple IPv6 routes - to any IPv6 destination on Earth March 2016

11. doc.: IEEE 802.15-16-0238-00 Submission Trading throughput for Link Budget Some reference numbers Willem Mulder, Dialog Semiconductor11 scenariopn seq lengthdatabitsproc gain note 11.08128.00.0 dB no DSSS 28.01016.09.0 dB todays symbol detector (32 chips per 4 data bits) 3320.025.425.1 dB todays preamble detector (320 chips per bit) 4508.016.027.1 dB 18 dB on top of the default 802.15 proc gain 51016.08.030.1 dB 21 dB on top of the default 802.15 proc gain 68128.01.039.1 dB 30 dB on top of the default 802.15 proc gain pn-codes shall have a regular/repeating stucture (correlator complexity) March 2016

12. doc.: IEEE 802.15-16-0238-00 SubmissionWillem Mulder, Dialog Semiconductor12 1.Broad Market Potential a)Broad sets of applicability. b)Multiple vendors and numerous users. 2.Compatibility a)Compliance with IEEE Std 802 b)Compliance with IEEE Std 802.1D c)Compliance with IEEE Std 802.1Q 3.Distinct Identity a)Substantially different from other IEEE 802 standards. b)One unique solution per problem (not two solutions to a problem) 4.Technical Feasibility a)Demonstrated system feasibility b)Proven technology, reasonable testing c)Confidence in reliability 5.Economic Feasibility a)Known cost factors, reliable data b)Reasonable cost for performance c)Consideration of installation costs The proposal: To develop an optional adaptive throughput/link-budget allocation mode for the 802.15.4 PHY The 5 IEEE 802 LMSC PAR review criteria : March 2016