cyber physical systems

1. CSC5930/9010: Security and Privacy in
Cyber-physical Systems
Lecture 1: Introduction to CPS/IoT

2. Slide 2
What are “Cyber- Physical Systems”?
• Cyber – computation, communication, and
control that are discrete, logical, and switched
• Physical – natural and human-made systems
governed by the laws of physics and operating
in continuous time
• Cyber-Physical Systems – systems in which
the cyber and physical systems are tightly
integrated at all scales and levels.

3. Slide 3
What are “Cyber- Physical Systems”?
• Cyber-physical systems (CPSs) are physical and engineered systems
whose operations are monitored, coordinated, controlled and
integrated by a computing and communication core.
• By merging computing and communication with physical processes,
CPS brings many benefits:
– Safer and more efficient systems
– Reduce the cost of building and operating systems
– Build complex systems that provide new capabilities

4. Slide 4
What are “Cyber- Physical Systems”?
• Technological and Economic Drivers
– The decreasing cost of computation, networking, and sensing
– Computers and communication are ubiquitous, enables national or global scale
CPSs
– Social and economic forces require more efficient use of national
infrastructure.

5. Slide 5
Characteristics of Cyber-physical Systems
• Some defining characteristics:
– Cyber – physical coupling driven by new demands and applications
•Cyber capability in every physical component
•Large scale wired and wireless networking
•Networked at multiple and extreme scales
– Systems of systems
•New spatial-temporal constraints
•Complex at multiple temporal and spatial scales
•Dynamically reorganizing/reconfiguring
•Unconventional computational and physical substrates (Bio? Nano?)

6. Slide 6
Characteristics of Cyber-physical Systems (cont’d)
– Novel interactions between communications/computing/control
•High degrees of automation, control loops must close at all scales
•Large numbers of non-technical savvy users in the control loop
– Ubiquity drives unprecedented security and privacy needs
– Operation must be dependable, certified in some cases

7. Slide 7
Characteristics of Cyber-physical Systems
• What they are not:
– Not desktop computing
– Not traditional, post-hoc embedded/real-time systems
– Not today’s sensor nets

8. Slide 8
CPS adoption’s increasing…
• CPS offers immense benefit
– Healthcare, home, vehicle
automation, industrial logistics etc.

9. Slide 9
The rise of CPS devices

10. Slide 10
Which gives rise to Internet of Things…
• Internet of Things and Moore’s Law
– Based on Moore’s Law, the transistors in a dense integrated circuit doubles
every two years
– This has given rise to affordable, more powerful, and highly computational
devices aka “Things”.

11. Slide 11
The rise of connected heterogeneous devices…
Source: CISCO

12. Slide 12
Heterogeneous device connectivity
• Today, we see “smart” non-traditional devices being connected to the
internet.
– Some home appliances such as toasters, washing machines, lightbulbs now are
internet connected
• Heterogeneous devices communicate with each other as well.
– Alexa controls home appliances such as switching on a toaster, controlling the
thermostat

13. Slide 13
What are Internet of Things?
• Heterogeneous device a.k.a “Things” with sensing and actuating
capabilities connected via a shared network.
– Network is not limited to the internet.
• Characteristics:
– Interconnectivity
– Heterogeneity
– Dynamic Changes
– Scalability

14. Slide 14
IoT Scenario
Motion sensor
Motion sensor
Motion sensor
ECG sensor
Internet

15. Slide 15
IoT Architecture
Cloud Layer
Gateway Layer
Device Layer
Sensor-Actuator Layer
Increasing
resource
constraint

16. Slide 16
IoT Architecture
Cloud Layer
Gateway Layer
Device Layer
Sensor-Actuator Layer
Increasing
resource
constraint
Edge devices consists of a
combination of the Device
layer and Sensor- Actuator
Layer
Fog devices consists of a
Devices contained in the
gateway layer.

17. Slide 17
IoT Architecture
• Cloud Layer:
– Consists of Servers and Cloud-based infrastructures
• Gateway Layer:
– Consists of devices which acts as an intermediary between the cloud and
Device layer (e.g network gateway devices, desktop servers).
• Device Layer:
– Also known as “Things”.
– Consists of devices with mostly constrained memory capabilities (e.g
smartphones)
• Sensor and Actuator Layer:
– Performs actions such as sensing data from the environment.
– Actuator acts on data sensed

18. Slide 18
Fog/Edge Devices
• Fog Devices:
– Devices with closer proximity to end user devices
– Larger storage/computational abilities than edge devices (e.g device gateways,
routers)
• Edge Devices
– End user devices
– Constrained memory (e.g smart watches, tvs, phones)

19. Slide 19
Overview: Hardware Platform
The Internet
Network
“Thing”
Sensors &
Actuators
Communications
User/Environment
Servers
2 sensors
IEEE 802.15.4
2.4GHz RF System
XM1000
Device
level
Network
level
The
Internet
Gateway

20. Slide 20
• Sensors:
– They are mainly input components
– They sense and collect surrounding information
– Basically three types:
•Passive, omnidirectional (e.g. mic)
•Passive, narrow-beam sensor (e.g. PIR)
•Active sensors (e.g. sonar, radar, etc.)
• Actuators:
– They are mainly output components
– They alter the surrounding. Some examples:
•Adding lighting, heat, sound, etc.
•Controlling motors to move objects
•Displaying messages
Sensors & Actuators
20

21. Slide 21
• We can turn almost every object into a “thing”.
• A “thing” still looks much like an embedded system currently.
• A “thing” generally consists of four main parts:
– Sensors & actuators
– Microcontroller
– Communication unit
– Power supply
• A “thing” has the following properties:
– It’s usually powered by battery. This implies limited source of energy.
– It’s generally small in size and low in cost. This limits their computing
capability.
– It doesn’t usually perform complicated tasks.
• Power consumption is the main design issue.
Things

22. Slide 22
• A “thing” always feature communications for connecting to other
devices.
• The Role of Communications
– Providing a data link between two nodes
• Communication type:
– Wired (e.g. copper wires, optical fibers)
– Wireless (e.g. Radio Frequency , Infrared).
• Popular RF-based communication solutions:
– IEEE 802.15.4
– IEEE 802.11 (or Wifi)
– Bluetooth
– Near Field Communication (NFC), e.g. RFID
Communications

23. Slide 23
• The Roles of Networks
– Managing nodes (discovery, join, leave, etc).
– Relaying data packets from the source to the destination node in the network.
• Networks are a distributed system. All nodes need to perform
networking related tasks.
• RF-based Network in IoT is usually a Wireless Multi-hop Network.
Some examples:
– Wireless Sensor Networks (WSNs)
– Mobile Wireless Ad hoc Networks (MANETs)
– Wireless Mesh Networks (WMNs)
– Vehicular Ad Hoc Networks (VANETs)
– and others...
• Main concern: Reliability & Performance
Networks

24. Slide 24
• The Internet serves as a wide area networking for a local network.
• The Internet uses TCP/IP. This implies that things must also support
TCP/IP.
• Gateway (or sink)
– For a practical deployment, a gateway is often needed in a network.
– It offers relaying packets between the network and the Internet.
The Internet
24
The Internet
Gateway
Data link
Network

25. Slide 25
Looming problem is insecurity
• Data Breaches
– CPS: large-scale, long-term, distributed data
– Attacker: Sell or hoard personal information
• Malware
– CPS: Tight time horizons and UX focused
– Attackers: Excess time and broad attack surfaces

26. Slide 26
Security flaw example: Jeep Remote Hijack
Source: https://www.wired.com/2015/07/hackers-remotely-kill-jeep-highway/
• Hacked via entertainment
system.

27. Slide 27
Source: www.owasp.org/index.php/OWASP_Internet_of_Things_Top_Ten_Project
Top Ten Device Vulnerabilities
1 Insecure Web Interface
2 Insufficient Authentication/Authorization
3 Insecure Network Services
4 Lack of Transport Encryption
5 Privacy Concerns (Data Collection)
6 Insecure Cloud Interface
7 Insecure Mobile Interface
8 Insufficient Security Configuration
9 Insecure Software/Firmware Updates
10 Poor Physical Security
Looming problem is device insecurity
Trusting
device end-
points is hard

28. Slide 28
References
• Kang G Shin “Lecture Note #2 EECS 571 Cyber-Physical Systems”
[PowerPoint Slides]. Retrieved from
https://www.eecs.umich.edu/courses/eecs571/lectures/lecture2-intro-
of-CPS.pdf
• Tameer Nadeem “Cyber Physical Systems Seminar” [PowerPoint
Slides]. Retrieved from
https://www.cs.odu.edu/~nadeem/classes/cs795-CPS-
S13/material/Lec-01_Course-Introduction.pdf
• NIST “Framework for Cyber-Physical Systems”
https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.1500-
201.pdf