This document discusses architectural approaches for integrating sensors into Internet of Things (IoT) solutions. It addresses the need for standards to reduce development time and cost for mid-market IoT applications. The document examines common hardware architectures and communication protocols used for sensor connectivity. It analyzes connectivity options like USB, Bluetooth Smart, and Zigbee. The goal is to support many application areas through common classes and profiles, though more standardized options are still needed for many domains.

1. Solid-Motion
Duncan McDonald
Founder Solid-Motion
3/6/2015
Architectural Approaches to
Integrating Sensors in IOT
Solutions

2. Todays Discussion
• Standards Can Substantially Reduce Development Time
and Cost for Mid-Market IoT Solutions
• Open source is best, but low cost or free “proprietary
standards” are OK too
• Not considering high level messaging and
communication protocols
– DDS, JMS, MQTT, CoAP, XMPP, AMQP, REST, LwM2M, etc.
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3. IoT ≠
Introduction
Remember, circa 2004 IoT was all about telemetry
and control of manufactured goods and
distributed assets. IoT still evolving!
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4. One More Time: What is IoT?
• All objects have an IP address
• In the context of current IoT solutions, the
direction is to have an internet device with at
least one smart sensor
• Typical architecture is a microcontroller for
the sensor interface and a microprocessor for
data processing and the internet interface
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5. Three Cost Scenarios
*Everything else (mid-market)
• Sensor/processor within one
order of magnitude
• Automotive
• Medical /Healthcare
• Industrial
• Scientific
Processor Cost
SensorCost
X Sensor cost << processor cost; consumer products
X Sensor cost >> processor cost; large system
X
X X
X
X
Sensor cost  processor cost; everything else*
Cost breakdowns vary
• Sensor cost
• Processor cost (including
software)
• Packaging cost (fixed)
Target for this discussion
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6. Development Cost vs Manufacturing Cost
Lots of optimization and customization required for low cost manufacturing
Duncan’s Law
DevelopmentCost
Manufacturing Cost Manufacturing Volume
DevelopmentCost
First Corollary
Consumer
Large Systems
Everything else
(mid-market)
6Solid-Motion IoT Summit 2015

7. Standards Reduce Development Cost
• Standards Can Substantially Reduce
Development Time and Cost for Mid-Market
Solutions
• Standards are important for consumer
products, but more about the ecosystem than
about development cost
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8. Typical HW Architecture
• Smart sensor
– Sensor; could be detached sensor
– Sensor memory
• Microcontroller
– No operating system; “code on bare metal”
• Processor
– Operating system
– Radio
– Cell phones, tablets, or laptops are good candidates
Microcontroller
Wired interface Wired or wireless
interface
Processor
Wireless
interface
Internet
Sensor
Memory
Sensor
Memory
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9. Data and Layers
Rough analogy to OSI model
I’ll use this model
Data
Data
Segments
Packets
Frames
Bits
Data
Presentation
Session
Transport
Network
Data Link
Physical
Application
OSI Model
Data Layer
Data structures
Messages
Data
Packets
Frames
Bits
Connector
Application
Communication
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10. Microcontroller
Wired interface Wired or wireless
interface
Processor
Wireless
interface
Internet
Sensor
Memory
Sensor
Memory
No connector
standards!
Sensor Connectors
Packets
Frames
Bits
Connector



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11. Microcontroller
Wired interface Wired or wireless
interface
Processor
Wireless
interface
Internet
Sensor
Memory
Sensor
Memory
• 1-Wire (proprietary)
• SPI
Memory Connection
Frames
Bits
Connector



Data structures
IEEE standard 1451.4 (TEDS) available
for high-level sensor interface
• Template based
• Or XML
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12. Microcontroller
Wired interface Wired
interface
Processor
Wireless
interface
Internet
Sensor
Memory
Sensor
Memory
USB
USB Class
Microcontroller to Processor (M2P)
Wired - USB
Data structures
Messages
Data
Packets
Frames
Bits


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13. USB & USB Classes
• Insanely wide platform support – no additional
hw required
• If you can use a USB Class that has wide OS
support, you won’t have to write a driver.
– HID, mass storage, image, audio, video, etc.
– Personal Healthcare not natively supported yet
• Big time/cost savings!
• No open source USB.org compliant software
stack
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14. Microcontroller Processor
Wireless
interface
Internet
Sensor
Memory
Sensor
Memory
Microcontroller to Processor (M2P)
Wireless - Zigbee
Data structures
Messages
Data
Packets
Frames
Bits
Application


Zigbee Pro/IP (proprietary)
Zigbee/Xbee (proprietary)
IEEE 802.15.4
Zigbee
receiver
Wireless
interface
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15. 6LoWPAN
Data structures
Messages
Data
Packets
Frames
Bits
Application


IEEE 802.15.4
Microcontroller to Processor (M2P)
Wireless – 6LoWPAN
IPv6
TCP/IP
Has anyone implemented
6LoWPAN without using an
OS?
Microcontroller Processor
Wireless
interface
Internet
Sensor
Memory
Sensor
Memory
Wireless
interface
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16. Microcontroller Processor
Wireless
interface
Internet
Sensor
Memory
Sensor
Memory
Data structures
Messages
Data
Packets
Frames
Bits
Application


Microcontroller to Processor (M2P)
Wireless – BlueTooth Smart (BLE)
Wireless
interface
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Bluetooth Smart profiles
Blue Tooth Smart

17. BlueTooth Smart
• Wide platform support – no additional hw
required
• Wide OS support – no driver needed for basic BT
• Big cost/time savings!
• Not nearly as many profiles (classes) natively
supported as USB
• BlueTooth health device profile (HDP) natively
supported on Android
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18. Summary
• Few issues up to the M2P link
– No connector standards for detached sensors
– Smart sensor memory description
• Templates very limited, no reference implementation
• XML rarely used
• Have two very well supported M2P links for mid-market IoT
 USB (wired)
 BlueTooth Smart (wireless)
 (Zigbee/Xbee requires additional hw to support M2P link)
• Still have bottlenecks though
– OS support of existing classes/device profiles limited
– More classes/profiles needed
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19. The Goal is to support many IoT Solutions
A lot more Classes and Profiles are needed
• Environmental monitoring
• Infrastructure management
• Manufacturing
• Energy management
• Medical and healthcare systems
• Building automation
• Transportation
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20. Thank You!
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Comments, questions, complaints, corrections
dmcdonald@solid-motion.com

21. Solid-Motion IoT Summit 2015 21
Back-up

22. USB Class Support in Win 7
USB-IF class code
Device setup
class
Windows 7
support
Audio Media 
Communications and CDC
Control
Modem 
Net -
HID
(Human Interface Device)
HIDClass 
Physical - -
Image Image 
Printer USB 
Mass Storage USB 
SCSIAdapter -
Hub USB 
USB-IF class code
Device setup
class
Windows 7
support
CDC-Data - -
Smart Card SmartCard
Reader

Content Security - -
Video Image -
Personal Healthcare - -
Audio/Video Devices - -
Diagnostic Device - -
Wireless Bluetooth 
Miscellaneous 
Application Specific - -
Vendor Specific - -
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23. BLE Profile Support in Android
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Profile Android Support
A2DP Advanced Audio Distribution profile

EXTRA_PREVIOUS_STATE Extra for the connection state intents
of the individual profiles

EXTRA_STATE Extra for the connection state intents
of the individual profiles

GATT Generic Attribute Profile 
HEADSET Headset and Handsfree profile

HEALTH Health Profile 
List of Profiles supported by the standard is quite large