Introduction to the Data-Distribution Service (DDS): Context and Applications. This 50 minute presentation summarizes the main features of DDS including the information model, the type system, and security as well as how typical applications use DDS. It was presented at the Canadian Government Information Day in Ottawa on September 2018. There is also a video of this presentation at https://www.youtube.com/watch?v=6iICap5G7rw.

1. Data-Distribution Service (DDS)
Gerardo Pardo, Ph.D. RTI CTO
Co-Chair OMG DDS SIG
September 2018

2. 2
Understanding Connectivity
Understanding DDS
DDS Applications

3. © 2018 Object Management Group 3
The Industrial IoT is Smart Machine
Infrastructure
Industrial Internet of Things (IIoT)
Consumer Internet of Things (CIoT)
80%
of hype
80%
of value

4. Industrial Internet Consortium:
~250 Companies, 30+ Countries
IIC Founding and Contributing Members
The World’s Largest IoT Consortium
The IIC created the IIoT market

5. IIoT Connectivity Stack Model
Participant X
Connectivity
Information
Networking
IICF Focus
Information (Data in Context)
Participant X
Transport
Link
Framework
Distributed Data
Interoperability and Management
Physical
Network
Participant Y
Data (State, Events, Streams)
Messages
Packets
Frames
Bits
Transport
Link
Framework
Distributed Data
Interoperability and Management
Physical
Network
Technical
Interoperability
(bytes)
Syntactic
Interoperability
(data structures)
Semantic
Interoperability
(data context)

6. IIOT Connectivity Standards
Manufacturing Origin
TSN /
Ethernet
(802.1,
802.3)
DDS
Wireless
PAN
(802.15)
Wireless
2G/3G/LTE
(3GPP)
Wireless
LAN
(802.11 Wi-
Fi)
Internet Protocol (IP)
CoAP MQTT
Web
Services
Wireless
Wide Area
(802.16)
HTTP
DDSI-RTPS
oneM2M OPC-UA
OPC-UA Bin
Telecommunications Origin
UDP TCP
TCP
Transport
Link
Framework
Distributed Data
Interoperability and Management
Physical
Network
Healthcare Transportation
Manufacturing
… …
Energy &
Utilities

7. Selection Criteria
Core Standard Criterion DDS Web Services OPC-UA oneM2M
1 Provide syntactic interoperability ✔ Need XML or JSON ✔ ✔
2 Open standard with strong independent, international governance ✔ ✔ ✔ ✔
3 Horizontal and neutral in its applicability across industries ✔ ✔ ✔ ✔
4 Stable and proven across multiple vertical industries Software Integration &
Autonomy
✔ Manufacturing
Smart City
Pilots*
5 Have standards-defined Core Gateways to all other core connectivity
standards Web Services,
OPC-UA, oneM2M*
DDS, OPC-UA,
oneM2M
Web Services,
DDS, oneM2M*
Web Services,
DDS*
6 Meet the connectivity framework functional requirements
✔ ✗
Pub-Sub in
development
7 Meet non-functional requirements of performance, scalability,
reliability, resilience ✔ ✗
Real-time in
development
Reports not yet
documented or
public
8 Meet security and safety requirements ✔ ✔ ✔ ✔
9 Not require any single component from any single vendor ✔ ✔ ✔ ✔
10 Have readily-available SDKs both commercial and open source ✔ ✔ ✔ ✔
* = work in progress , ✔ = supported, ✗ = not supported GREEN = Gating Criteria

8. Using Connectivity Middleware for Application Development
Application
Middleware
Operating
System
Network
Application
Middleware
Operating
System
Application
Middleware
Operating
System

9. 4th Gen Middleware: Data-Centric Publish-Subscribe
Broadcast
Publish/Subscribe
Fieldbus, CANbus,
OPC UA Pub-Sub
Data-Centric
Publish-Subscribe
DDS
Brokered
Publish/Subscribe
Queueing
MQTT, XMPP
AMQP, Kafka
Brokered
ESB
Daemon
Point-to-Point
Client/Server
TCP, REST,
WS*, OPC UA
CORBA, Thrift
Shared Data Model
DataBus

10. 10
Complexity of the Application Code
Network
Application
Middleware
Operating
System
Application
Operating System
Quality of
Service
Discovery
Data Resource
Model
Id and Addressing
Data Type
System
State
Management
Connectivity Transport
Connectivity Framework
Application
Operating System
Quality of
Service
Discovery
Data Resource
Model
Id and Addressing
Data Type
System
State
Management
Connectivity Transport

11. DDS–Based Integration
Light-Weight
Clients
Connectivity Core
Standard (HTTP/REST)
DDS-WEB
Gateway
IIoT System
Real-Time
Decisions
Gateway
Sleep/Wake Clients
OPC UA/DDS
Gateway
Connectivity Core
Standard (OPC-UA)
Connectivity Core Standard (DDS)
Manufacturing Workcells
Mobile and Web User Interfaces
Autonomy
Equipment

12. DDS is broadly used across the IIoT
Real World Systems in:
– Healthcare
– Transportation
– Communications
– Energy
– Industrial
– Defense

13. Example: Grand Coulee Dam
Radar
Radar
Displays Logging
Existing SCADA
(to be replaced)
Alarming
Monitor
Interested in
many quantities
IPC
IPC
IPC
Segment Bus (DDS)
Redundant
Routing
IPC
IPC
IPC
Segment Bus (DDS)
IPC
IPC
IPC
Segment Bus (DDS)
VPN/Firewall
Local quantity
interest
TCP (WAN)
VPN/Firewall
VPN/Firewall
Control Room Bus (DDS)
Control
Room
Migration
Server

14. Example: Autonomous Vehicles
Sensing
Planning
Vehicle
Control
Logging
DDS DATABUS
Traffic Maps
Error
Management
Situation
Awareness
Situation
Awareness
Cameras,
LIDAR, Radar…
Cameras,
LIDAR, Radar…
Cameras,
LIDAR, Radar…
Data Fusion Cameras,
LIDAR, Radar…
Localization
Vehicle
Platform
Visualization Navigation
DDS DATABUS

15. Example: Clinical Decision System Architecture
Room Domain Bus
Central Domain Bus
Room Domain Bus
Admin Domain Bus (Cloud)
Patient Monitoring Devices
Workstations, Storage,
Historian
Gateway, IX, Enterprise, 3rd Party
DDS
Router
DDS
Router
DDS
Router

16. Understanding the DDS
Connectivity Framework

17. DDS Specification family
DDS v 1.4
RTPS v2.2
DDS-SECURITY
DDS-RPC
DDS-XTYPES
Application
TCP UDP DTLS TLS
DDS-C++ DDS-JAVA DDS-IDL-C DDS-IDL-C#
SHARED-MEMORY
IP
IDL
4.
TSN
Ethernet
DDS-WEB
DDS-OPC
UA
HTTP
UA
TCP

18. Timeline
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a
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D
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4
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1
2004 2006 2007 2008 2010 2012 2014 2016 2018
2017
2015
2013
2005 2009 2011

19. DDS Model: Virtual Global Data Space
Topic A
QoS
Topic C
QoS
Topic D
QoS
DDS DOMAIN
Persistence
Service
Recording
Service
CRUD operations
Topic B : “Turbine State”
Source (Key) Speed Power Phase
WPT1 37.4 122.0 -12.20
WPT2 10.7 74.0 -12.23
WPTN 50.2 150.07 -11.98
QoS

20. Data-Centric Communications Model
• Participants scope the global data space (domain)
• Topics define the data-objects (collections of subjects)
• DataWriters publish data on Topics
• DataReaders subscribe to data on Topics
• QoS Policies are used configure the system
• Listeners are used to notify the application of events
Reader
“Alarm”
Domain
Participant
Writer
“Alarm”
Domain
Participant
Listener
Offered
QoS Listener
Got new
data
Requested
QoS
New
subscriber!
“Alarm” Topic
Topic2
Topic2
Request <= Offered
QoS compatibility
checking and run-time
monitoring

21. Quality of Service (QoS) Policies
QoS Policy
DURABILITY
HISTORY
LIFESPAN
WRITER DATA LIFECYCLE
READER DATA LIFECYCLE
ENTITY FACTORY
RESOURCE LIMITS
RELIABILITY
TIME BASED FILTER
DEADLINE
CONTENT FILTERS
Cache
User
QoS
Delivery
Presentation
Availability
Resources
Transport
QoS Policy
USER DATA
TOPIC DATA
GROUP DATA
PARTITION
PRESENTATION
DESTINATION ORDER
OWNERSHIP
OWNERSHIP STRENGTH
LIVELINESS
LATENCY BUDGET
TRANSPORT PRIORITY

22. © 2010 Real-Time Innovations, Inc.
RTPS Protocol optimized for real-time
• Full peer-to-peer protocol
• No required brokers or servers
• Adaptable via QoS
• Reliability, timeouts, message priority
• Native reliable multicast support
• Uses transport multicast, if available, else unicast UDP
• Robust to disconnects
• Maintains session above (UDP) transport
• Efficient data encapsulation
• Binary XCDR
• Built-in availability and durability
• Durable & Persistent data, Historical cache, Failover support
RTPS

23. Data and Service Definition
DDS-XTYPES and IDL4 standards
• Logical Data Model and Service Interfaces
• Portable: Language-Independent Type System
• Safe: Rules for Type Compatibility
• Flexible: Types/Interfaces expressed in IDL or XML
• Interoperable System Evolution
• Types/Services changes (add, remove, reorder, …)
• Incremental/Partial upgrades
• Dynamic API’s to access data and types
• Systems that adapt at run-time
• Efficient binary serialization
@mutable
struct ShapeType {
@key string color;
@range(0, 200) long x;
@range(0, 250) long y;
@optional @min(5) float size;
};
struct ShapeTypeExt : ShapeType {
@unit(“meter”) long x;
};
/* Service definition */
enum Command { START, STOP };
@service
interface RobotControl
{
void command(Command com);
float setSpeed(float speed)
raises (TooFast);
float getSpeed();
};

24. DDS Applications

25. Energy
Grand
Coulee Dam

26. Defense

27. Healthcare

28. Transportation

29. Run 24x7 Across Continents
We selected Object Management
Group (OMG) DDS standard for its
high security rating; its wide
support of tools and programming
languages, and its reputation for
performance, scalability, and 24/7
reliability
Sid Koslow, Chief Technology
Officer, NAV CANADA
Air Traffic Control for Canada
2nd largest ANSP in the world
7 major centers

30. Siemens Wind Power Distributed Control
• Wind turbine farms can include 500
turbines, 100m blades
• Gust control across the array
requires fast communications with
dynamic, selective filtering
• DDS enables large, distributed
intelligent machines

31. Grand Coulee Dam
• DDS controls the 6.8 GW Grand Coulee Dam
• Largest power plant in North America
• Fastest-responding major power source on the
Western Grid
• System live since Jan 2014

32. Audi Hardware-in-the-loop simulation
• Audi hardware-in-the-loop simulation feeds
realistic data to components for testing
• The system offers plug-n-play between
simulation vendor solutions
• DDS software enables a modular test environment
that scales to work with hundreds of devices

33. DDS deployed across Navy Systems
• Most US and NATO Navy systems
• Lockheed Aegis
• Raytheon DDG 1000
• Raytheon SSDS
• LCS (Lockheed and GDAIS)
• Raytheon LPD-17
• Many more, US and allies
• Highly distributed systems include
radar, weapons, displays, controls
• Standards-based, high-performance
middleware breaks vendor lock-in,
drives interoperability ,and future-
proofs the architectural design

34. ©2017 Real-Time Innovations, Inc.
GE Transportation
GE Transportation freight and
passenger locomotives require safe
and reliable control, signaling, and
communications
The system is being developed using
SysML, Simulink, and DDS

35. Security

36. Copyright © 2017 OMG. All rights reserved. 36
Example Threat Analysis
Duke Energy Emerging Technology Office
OpenFMB Cyber Security Overview

37. OpenFMB Case Study
Node
3G, LTE, Wi-Fi,
Fiber, Ethernet,
RF ISM, or PLC
Node
Key Observations:
1. Single-Purpose Functions
2. Proprietary & Silo’ed systems
3. Latent , Error-prone Data
4. OT/IT/Telecom Disconnected
5. No Field Interoperability!
UTILITY
CENTRAL
OFFICE
Head
End A
Vendor A Solution
Private
Carrier
R
Head
End C
Vendor C Solution
Public
Carrier
900MHz
ISM
Enterprise
Service
Bus
Head
End B
Vendor B Solution
Proprietary
Network
R
UTILITY
CENTRAL
OFFICE
Head
End A
Head
End B
Head
End C
Enterprise
Service
Bus
Open
Field
Message
Bus
Any Medium
CIM
DNP3
61850+CIM
IoT Pub/Sub
Key Observations:
1. Multi-Purpose Functions
2. Modular & Scalable HW&SW
3. End-to-End Situational Awareness
4. OT/IT/Telecom Convergence
5. True Field Interoperability!
Sunspec
Modbus
C12.22
or CoAP
MESA
DNP3
61850
GOOSE

38. •Loss of power, small areas to wide scale
•Loss of life
•Safety and Security Issues
•Failure of critical infrastructure operation
•Masquerade / Takeover control applications
•Control the Switch / Breaker / Recloser / Voltage Regulator / PCC
•Spoof Status
•Change Setpoints, Disable Protection
•Drive Distributed Denial-of-Service attack (DDoS)
38
OpenFMB Case Study
Copyright © 2017 OMG. All rights reserved.

39. © 2018 Object Management Group 39
Connected System - Ideal
39

40. Connected System - Real

41. © 2018 Object Management Group 41
Who Uses DDS Security
• Military:
• Avionics
• Naval
• Unmanned Vehicles
• Ground Stations
• Commercial:
• IIoT Systems
• Avionics
• Automotive
• Consumer Electronics
• Energy Solutions / Smart Grid
• Medical Devices

42. © 2018 Object Management Group 42
DDS Security Standard
• DDS entities are authenticated
• DDS enforces access control for
domains/Topics/…
• DDS maintains data integrity and
confidentiality
• DDS enforces non-repudiation
• DDS provides availability through
reliable access to data
…while maintaining DDS interoperability & high performance

43. © 2018 Object Management Group 43
DDS Security: Plug-in Architecture
• Standardized API
• Interface between modules
and DDS Security protocols
• Modules may be Standard
or Custom
• Includes all aspects of
secure communications
• Standardized modules
• Interoperable
• Use common crypto
algorithms
Logging Plugin
Authentication
Plugin
Access Control
Plugin
Cryptographic
Plugin
Standardized
Plugin
API
Security

44. •Apply security policies
•Integrity / Encryption / Access Controls
•With fine grained controls
•Individual Topics
•Application Data, Discovery Data, Liveliness Data
44
DDS Security: Configurability
© 2018 Object Management Group
Periodic Data: Discovery Open, Data Integrity
Control Data: Discovery Open, Data Encrypted
Config Data: Discovery Encrypted, Data Encrypted

45. Conclusion

46. Why DDS ?
Data-centric
Naturally
modular
Naturally
scalable
Resiliency
High
reliability
Maximum
up-time
Performance
Minimum
latency
Maximum
throughput
Faster
development
SOA-like
architecture
Code
re-use
Standards
based
No vendor
lock-in
Future
proof
Security
Built-in
Security,
Fine-
Grained
Access Ctrl

47. DDS and the Industrial Internet of Things
• Reliability: Severe consequences if
offline for 5ms (or 5 min)
• Real-time: measure in ms or µs
• Interface scale: 10+
applications/teams
• Dataflow complexity: data has many
destinations
• Architecture: Next generation IIoT
Deployed in 1000s of Systems Industrial IoT Systems
Industries: Energy, Industrial Control, Transportation, Healthcare, Defense
3+ Yes?

48. Thank You!
http://portals.omg.org/dds/
48