Energy balancing
RPL-based routing for
Internet of Things
SPEAKER: CHUN-WEI CHANG
ADVIDOR: DR. HO-TING WU
DATE: 2017/01/04
Outline
• Introduction
• Background
• Energy Balancing Scheme for RPL-Based Routing
• Simulation Setup
• Simulation Result and Analysis
• Conclusion
• Reference
2
Introduction
• Battery
• Energy balancing
S
3
RPL
• Select the path to sink by Rank
• 𝑅𝑎𝑛𝑘𝑝𝑎𝑟𝑒𝑛𝑡 < 𝑅𝑎𝑛𝑘𝑐ℎ𝑖𝑙𝑑𝑟𝑒𝑛 (𝑅𝑎𝑛𝑘𝑠𝑖𝑛𝑘 = 0)
4
Object Function
Mote/Link Metric
Rank
Hop-Count
Cost
Latency
Cost/65536
ETX
Cost
5
Expected Transmission Count (ETX)
• 𝐸𝑇𝑋 =
1
𝑑𝑓 ×𝑑𝑟
[RFC 6551]
𝑑𝑓
probability that a data packet successfully arrives at the recipient
𝑑𝑟
probability that the ACK is successfully received at the sender
• Better delay but may cause energy unbalance.
6
Mote Energy Consumption
• TIME
• LPM (Low-Power Mode)
• CPU
• RADIO
• LISTEN
• TRANSMIT
7
Mote Energy Measurement
• Hardware-based vs Software-based
• Energy Consumption (EC)
•
𝐸𝐶
𝑉
= 𝐼𝑚 𝑡𝑚 + 𝐼𝑟 𝑡𝑟 + 𝐼𝑡 𝑡𝑡 +
• Depend on mote type
𝑖 𝐼𝑐𝑖 𝑡𝑐𝑖
V supply voltage
Ix current draw
t x the time has been running
m microprocessor
r
receive mode
t
transmit mode
𝑐𝑖 other components (LEDs)
8
Mote Energy Measurement
• Radio_time = LISTEN + TRANSMIT
• LPM
• CPU_time
• 𝐸𝐸 =
𝑅𝑎𝑑𝑖𝑜_𝑡𝑖𝑚𝑒
𝐶𝑃𝑈_𝑡𝑖𝑚𝑒
∗ 100
9
Energy Balanced Object Function
• OF e2eEnergy, OF1
• OF ETX+singleEnergy, OF2
• OF ETX+e2eEnergy, OF3
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Energy Balanced Object Function
• 𝑐𝑜𝑠𝑡 𝑁𝑃 , 𝑆 : the path cost value from N to S
via P
• 𝑐𝑜𝑠𝑡(𝑁, 𝑆): the path cost value from N to S via
current parent
• If 𝑐𝑜𝑠𝑡 𝑁𝑃 , 𝑆 < 𝑐𝑜𝑠𝑡(𝑁, 𝑆):
P become parent of N
11
ETX Link Metric
• OF ETX
• 𝑐𝑜𝑠𝑡 𝑁𝑝 , 𝑆 = 𝐸𝑇𝑋 𝑁, 𝑃 + 𝐸𝑇𝑋 𝑃, 𝑆
• 𝑅𝑎𝑛𝑘 𝑁 = 𝑅𝑎𝑛𝑘 𝑃 + 𝐸𝑇𝑋(𝑁, 𝑃)
12
Mote Energy Metric
• OF e2eEnergy, OF1
• 𝑐𝑜𝑠𝑡 𝑁𝑝 , 𝑆 = 𝑐𝑜𝑠𝑡 𝑃, 𝑆 + 𝐸𝐸(𝑃)
• 𝑅𝑎𝑛𝑘 𝑁 = 𝑅𝑎𝑛𝑘 𝑃 + 𝐸𝑇𝑋(𝑁, 𝑃)
13
Link Metric and Mote Energy Metric
• OF ETX+singleEnergy, OF2
• 𝑐𝑜𝑠𝑡 𝑁𝑝 , 𝑆 = 𝐸𝑇𝑋 𝑁, 𝑃 + 𝐸𝑇𝑋 𝑃, 𝑆 + 𝐾 × 𝐸𝐸(𝑃)
• OF ETX+e2eEnergy, OF3
• 𝑐𝑜𝑠𝑡 𝑁𝑝 , 𝑆 = 𝑐𝑜𝑠𝑡 𝑁, 𝑃 + 𝐸𝑇𝑋 𝑃, 𝑆 + 𝐾 × 𝐸𝐸(𝑃)
• 𝑅𝑎𝑛𝑘 𝑁 = 𝑅𝑎𝑛𝑘 𝑃 + 𝐸𝑇𝑋(𝑁, 𝑃)
14
Piggy-backing of the path cost in a DIO
• DAG Metric Container
15
Simulation Setup
Parameters
Values
Area
200x200m
Motes
25
Transmission Range
70m
Send Interval
60s
Simulation Times
30 minutes
16
Simulation Result and Analysis
• OF (ETX)
17
Simulation Result and Analysis
• OF1
18
Simulation Result and Analysis
• OF2
19
Simulation Result and Analysis
• OF3
20
Simulation Result and Analysis
21
Simulation Result and Analysis
22
Conclusion
• We proposed and evaluated three objective functions
involving the energy consumption estimation scheme (EE),
which is independent of mote type and does not involve
extra messages. Those objective functions use combination
of ETX and EE routing metrics. Simulations show that our
methods achieve better energy balance while keeping good
energy efficiency and PDR.
23
Reference
• Mai Banh, Nam Nguyen, Kieu-Ha Phung, Long Nguyen,
Nguyen Huu Thanh, Kris Steenhaut, "Energy balancing RPLbased routing for Internet of Things", in Communications
and Electronics (ICCE), 2016
24
Thanks
25