1. @matteocollina
matteocollina.com
IoT Day Trento 2013/04/09
Making things
that work with us!

2. Smartphones are
changing the world

3. How many people will own
a smartphone by 2014
1.000.000.000

4. Did you see
it coming
http://www.flickr.com/photos/12738000@N00/360231193/

5. Steve
did.
http://www.flickr.com/photos/noppyfoto/6216399465/

6. Thanks.
http://www.flickr.com/photos/noppyfoto/6216399465/

7. They didn’t!
...

8. What's next
(hint: it's a big number)
50.000.000.000

9. 1.000.000.000
50.000.000.000

10. 50.000.000.000
interconnected
"things"
by
2020

11. http://www.flickr.com/photos/jurvetson/2798315677

12. Monitor my
house
temperature
Goal:

13. I want to
chat with
my house

14. >: hi house
hi matteo
>: what's the
temperature?
19

15. >: 4 8 15 16 23 42

16. Hubot © 2012-2013 GitHub Inc. All rights reserved.
Enter Hubot

17. A programmable robot
that is controlled through
chat
Hubot © 2012-2013 GitHub Inc. All rights reserved.

18. We can supercharge our house with hubot

19. module.exports = (robot) ->
robot.respond /what’s the temperature?/i, (msg) ->
msg.http("http://mchouse.it/temperature")
.header("Accept", "application/json")
.get() (err, res, body) ->
msg.send JSON.parse(body)
We can supercharge our house with hubot
How

20. In order to ask our temp
to hubot, we need to:
1. sense the temp
2. get the temp on the web
3. build a web API

21. From Hubot, I want to do
the equivalent of:
>: curl http://mchouse.it/temp
What about JSON

22. What protocol do we use
to push our temperature
to our API?
HTTP POST

23. http://www.flickr.com/photos/clearlyambiguous/48185613/
HTTP is slow and safe

24. We need a
fast, binary
protocol
http://www.flickr.com/photos/grrphoto/305649629

25. likes binary

26. To build a
social web of
things we
need to react
to events.

27. We need a
publish/subscribe
pattern.

28. HTTP

29. Devices need:
• binary protocol
• publish/subscribe

30. Binary vs REST
“Things” should
interact with our
lives, and all the
technology should
be built to make
them easy to use.
M2M protocols are
ad-hoc, and
researchers and
businesses focus on
low level problems.

31. • “things” exposed
with binary protocol
• publish/subscribe
• topics as the naming
system
• “things” exposed
to the web
• request/response
• URIs as the
naming system

32. MQTT is the state of
art protocol for the
Internet of Things
Mosquitto
Really Small
Message Broker

33. • the base element of the protocol is a topic
• devices and other systems can publish or
subscribe to topics

34. How to use
on

35. Step 1: download
PubSubClient, the
library for

36. on Arduino: Setup
String server = String("qest.me");
PubSubClient client =
PubSubClient(server,
1883,
callback);

37. if (!client.connected()) {
client.connect("arduino");
}
client.loop();
char s[10];
itoa(get_temperature(), s, 10);
client.publish("temp", s);
on Arduino: publishing

38. if (!client.connected()) {
client.connect("arduino");
}
client.loop();
char s[10];
itoa(get_temperature(), s, 10);
client.publish("temp", s);
on Arduino: publishing
This is called a topic,
and it is where we publish
things on MQTT.

39. speaks
, Hubot speak HTTP

40. speaks
, Hubot speak HTTP
Communication

41. QEST
Discover
qest.me

42. • MQTT broker
• REST interface
• HTTP semantics
• no QoS
• built in node.js
• will support MongoDB,
RabbitMQ and many others.
QEST
REST Server
Redis
MQTT Server
QEST
Data Layer
HTTP Clients MQTT Clients

43. QEST
• retains every message received
: MQTT to REST
curl -H "Accept: txt"
http://qest.me/topics/temp
client.publish("temp", "30");
• every topic has its own URI: /topics/<NAME>

44. QEST
• transform every HTTP PUT received into a
MQTT message
: REST to MQTT
void callback(char* topic, byte*
payload, int length) {
...
}
PubSubClient(server, 1883, callback);
client.subscribe("temp");
curl -X PUT -d '{ "housetemp": 42 }'
-H "Content-Type: application/json"
http://qest.me/topics/temp
• devices can listen directly to MQTT topics

45. Web App
Device
SCL
SDA
AREF
GND
IOREF
RESET
3V3
PWM
PWM
PWM
L
TX
RX
ON
ICSP
PWM
PWM
PWM
TX
RX
3
1
2
1
1
1
0
1
9 8
DIGITAL
7 6 5 4 3 2 1 0
1
5V Gnd
POWER
www.arduino.cc
ANALOG IN
Vin 0 1 2 3 4 5
Arduino UNO
IoT
Broker
QEST
state-of-art
approach to IoT apps
QEST-based
solution to IoT apps
Bridge
Web App
Device
SCL
SDA
AREF
GND
IOREF
RESET
3V3
PWM
PWM
PWM
L
TX
RX
ON
ICSP
PWM
PWM
PWM
TX
RX
3
1
2
1
1
1
0
1
9 8
DIGITAL
7 6 5 4 3 2 1 0
1
5V Gnd
POWER
www.arduino.cc
ANALOG IN
Vin 0 1 2 3 4 5
Arduino UNO

46. Hubot © 2012 GitHub Inc. All rights
Hubot Integration
module.exports = (robot) ->
robot.respond /qest check ([a-z0-9A-Z]+)/i, (msg) ->
topic = msg.match[1]
if topic?
msg.http("http://qest.me/topics/#{topic}")
.header("Accept", "application/json")
.get() (err, res, body) ->
msg.send JSON.parse(body)
else
msg.send "No topic specified"

47. • What devices can a user monitor?
• What devices can 'listen' to the
state of other devices?
• Who can access the devices state?
• Is the communication secure?
Security Issues

48. We need OAuth
for Devices!
I’m
working on
it!!

49. TL;DR
• The Internet of Things
will be big
• Devices need binary
and pub/sub protocols
• Devs need HTTP API
• QEST does both

50. Matteo Collina
Ph.D. Student @
University of Bologna
@matteocollina matteocollina.com

51. Credits
• Font-Awesome for the
Icons.
• Flickr for the CC
images.
• Balsamiq Mockup for
the iPhone Mockup.
• Unibo for my Ph.D.

52. Matteo Collina (matteo.collina2@unibo.it)
Thank You!
@matteocollina
http://www.flickr.com/photos/axel-d/479627824/

53. http://www.flickr.com/photos/alexindigo/1606826416
Any Questions?