SFPE Tech Talk 2012
BACnet Integration Topics
in Life Safety Systems
Jason Falbo, P.Eng, M.B.A
VP Engineering
The Mircom Group of
Companies
jfalbo@mircom.com
www.mircomgroup.com
ROADMAP
 Past Methods of Integration
 Industry Drivers for Change
 Details of the BACnet Protocol
 A quick application example
 Helpful Links and Self-Study Tips
for the Fire Protection Engineer
From Hardwired Interfaces to Software Interoperability
BRIEF HISTORY OF FIRE ALARM
SYSTEMS INTEGRATION
THE PAST: HARDWIRED INTERFACES
 A collection of dry contact
inputs/outputs were used to fulfill a
correlation matrix to meet a specific
project integration objective
 Relay Logic was used to design
complex interfaces
 Systems were poorly documented if
at all and nearly impossible to
maintain or extend
INTEGRATION: COMPLEX METHOD
Return Air Fire
Alarm Damper
Actuator Relay
Damper Status
Monitor Modules
Supply Air Damper
Actuator Relay
Return Air
Damper
CLOSED End
Switch Electrical
Supervisory
Device
Supply Air
Damper CLOSED
End Switch
Supervisory
Device
Return Air
Smoke Damper
Pneumatic
Actuator
Supply Air
Damper OPEN
Supervisory
Device
Supply Air Damper
Pneumatic Actuator
Supply Damper
Actuator Electrical
Supervisory Device
Return Air Smoke Damper
Actuator Electrical Supervisory
Device
Return Air
Damper OPEN
End Switch
Electrical
Supervisory
Device
Trends, History, and Purpose
MODERN DRIVERS FOR CHANGE
INDUSTRY TRENDS IN INTEROPERABILITY
Financial Services
 http://www.xbrl.org/
Healthcare
 http://www.hl7.org
Fire Protection
 http://www.bacnet.org/
INTEGRATION: COMPLEX METHOD
Return Air Fire
Alarm Damper
Actuator Relay
Damper Status
Monitor Modules
Supply Air Damper
Actuator Relay
Return Air
Damper
CLOSED End
Switch Electrical
Supervisory
Device
Supply Air
Damper CLOSED
End Switch
Supervisory
Device
Return Air
Smoke Damper
Pneumatic
Actuator
Supply Air
Damper OPEN
Supervisory
Device
Supply Air Damper
Pneumatic Actuator
Supply Damper
Actuator Electrical
Supervisory Device
Return Air Smoke Damper
Actuator Electrical Supervisory
Device
Return Air
Damper OPEN
End Switch
Electrical
Supervisory
Device
INTEGRATION: SIMPLIFIED METHOD
FACP with Native BACnet Interface
 Physical Ethernet port Connection on FACP Main Board
MD-871A Main Board
BACnet Ethernet Connection
THE FUTURE: SOFTWARE INTERFACES
BACnet: ANSI/ASHRAE Standard 135-1995: BACNet--A Data
Communication Protocol for Building Automation and Control Networks.
 1980’s saw a proliferation of computerized building systems and typically
systems from a specific manufacturer could not operate with other
manufacturer’s products (no “interoperability”)
 In1987 , Michael Newman of Cornell University formed a committee to
investigate creation of interoperable building systems protocol
 The BACNet standard’s first draft was published in 1991, and it became
a standard in 1995
 BACNet was designed to allow interoperable communication of
building automation and control systems for applications such as
heating, ventilating, air-conditioning control, lighting control, access
control, fire protection systems and their associated equipment.
BACNET STANDARD HAS BEEN ADOPTED
BY 612* MANUFACTURERS WORLDWIDE
Country
USA
Germany
Canada
Japan
Australia
United
Kingdom
China
Vendors
228
68
51
51
20
Country
Netherlands
Hong Kong
Poland
Sweden
Austria
Vendors
10
8
8
8
7
Country
Vendors
Finland
2
Ireland
2
Slovakia
2
New Zealand
2
Serbia
2
19
Taiwan
7
Spain
2
16
Malaysia
Czech
Republic
India
Israel
Brazil
South Africa
6
Argentina
1
5
Belgium
1
4
4
3
3
Croatia
Estonia
Hungary
Latvia
1
1
1
1
Korea
15
Switzerland
Denmark
France
Italy
15
11
11
11
http://www.bacnet.org/VendorID/index.html
*as of September 12th 2012
BACnet Implementation
BACNET IMPLEMENTATION CASE
STUDY
BACNET SETUP: STEP ONE (ACTIVATE)
 Use MGC’s Fire Alarm Panel Configurator to activate BACnet functionality:
 1. Run TCP/IP Services
 2. Activate BACNet Services
BACNET SETUP STEP TWO (EXPORT)
 Use Configuration tools to export automatically the list of auto-assigned
BACNET points for each object in the Fire Alarm Control Panel
BACNET SETUP STEP THREE (DEPLOY)
 Provide the list of
BACNet points to the
BMS system integrator
 The Integrator will map
the auxiliary system
activities to FACP point
state changes
BINARY INPUTS
LIFE SAFETY POINTS
BINARY INPUTS
LIFE SAFETY POINTS
INTEGRATION : OPTIMIZED METHOD
LIGHTING CONTROL
CLIMATE MONITORING
SECURITY-OCCUPANTMONITORING
VIDEO-SMOKE-CONFIRMATION
SAFE ELEVATOR EGRESS
SMOKE MANAGEMENT & CONTROL
How Does it Work?
BACNET PROTOCOL DEEP DIVE
PART I - BASICS
FIRST START WITH CHOICE OF BACNET
NETWORK ARCHITECTURE
High Speed Backbone LAN
(Fire Alarm)Network ID#2
BACnet
Workstation OpenGN
(Fire Alarm)Network ID#3
(Security & Access Control) Network ID#1 (HVAC/Fan Control) Network ID#4
NEXT: LEARN THREE RULES!
1. Every Device has a set of Objects
2. Every Object has a set of Properties
3. Messages & Services describe the above
BACNET OBJECT MODEL
BACNET OBJECT PROPERTIES CHANGE
BASED ON PHYSICAL EVENTS
 Smoke Alarm modeled as binary
input (alarm point)
 Addressable relay modeled as binary
output (supervised output circuit)
MOST USEFUL MESSAGES & SERVICES
 Who-Is and I-Am
 Who-Is and I-Am may be used to dynamically bind Device IDs (Device Object
Identifiers) to addresses
 ReadProperty
 ReadProperty-Request and ReadProperty-Response are used to “receive” a single
property of an object from a BACnet device
 WriteProperty
 WriteProperty-Request and WriteProperty-Response are used to “transmit” a single
property of an object between two BACnet devices
MAPPING FIRE ALARM DATA INTO
BACNET DATA (ALARM SCENARIO)
FIRE ALARM SIDE
 MANUAL STATION (Device)
 ADDRESS = N2L4A006
 ACTIVITY = TRANSITION FROM
NORMAL TO ALARM
 EPICS (VENDOR DATA KEY)
 PRESENT_VALUE =

‘0’ IF NORMAL OR

‘1’ IN ALARM
 STATUS FLAGS =

‘[0,0,0,0]‘ IF NORMAL OR

‘[1,0,0,0]’ IN ALARM
BACNET/BMS SIDE
 BINARY INPUT (Object)
 OBJECTID = 2004006
 PRESENT_VALUE = 1
 STATUS FLAGS = [1,0,0,0]
DRIVING ADOPTION THROUGH SPECIFICATION & REGULATION
LEARN MORE ABOUT BACNET
SELF STUDY & TIPS
 Tutorial, Overview
 http://www.bacnet.org
 Purchase the Standard
 http://www.ashrae.org/resources--publications/bookstore/standard-135
 Download your own BACNet stack and develop your own interface
 http://sourceforge.net/projects/bacnet/
 Test a product’s BACNet Interoperability level using VTS
 http://sourceforge.net/projects/vts/
 Specify BACNet into your projects!
 http://fire.nist.gov/bfrlpubs/build99/PDF/b99051.pdf  Guide To Specifying BACNet
THE END
For any questions/comments contact the author via email:
Jason Falbo, P.Eng, M.B.A
Vice President, Engineering
The Mircom Group of Companies (MGC™)
jfalbo@mircomgroup.com
Extra details for those interested
APPENDIX A
OBJECT MODELLING, SERVICES, SECURITY
BACNET PROTOCOL DEEP DIVE
PART II – ADVANCED TOPICS
BACNET MESSAGE ROUTING
 BACNet works on Open System Interconnection (OSI) model of
networking.
 BACNet works primarily on the Application, Network and Physical layer
of OSI. Other layers were omitted/consolidated to make protocol
efficient
 The diagram on the following slide shows how a packet is routed from a
bacnet compatible application layer through the network layer to the
physical layer.
APPLICATION
Event
Activation
GUI
Update
Application Engine
APPLICATION INTERFACE/
APPLICATION LAYER
Service Calls
(Who Is, Read Property,
Write Property etc.)
Request Generated
to Application
Encode Queue
To Application
Decoded Queue
BACNet Encoder
BACNet Decoder
Receive From
Application Queue
Send To
Application Queue
TSM MANAGER
Sending Queue
Receive Queue
Sending Thread
Receiving Thread
BACnet Packet
Network Packet
Network (LAN, WAN, Internet, etc.)
NETWORK LAYER
BACNET SECURITY
 BACnet Security model is optional to use. The intent of designing this
module is to provide peer entity, data origin and operator
authentication, as well as data confidentiality and integrity.
 BACnet Security architecture provides Device Authentications, Data
Hiding, User Authentication.
 BACnet Security model relies on the use of shared secrets called keys.
 Device Authentications and User Authentication are achieved through
the use of message signatures and shared signature keys.
 Data hiding is achieved through encryption of the secure payload and
shared encryption keys.
 Details on BACnet Security module can be found on :
 http://www.bacnet.org/Addenda/Add-2004-135g-PR1.pdf
BACNET SECURITY - SHARED KEYS
BACNet Security Key Pairs
General –
Network
Access Key
User
Authenticated
Application
Specific
Installation
Distribution
Device-Master
BACNET SECURITY – SECURING MESSAGES
Encrypted Security Payload – Secured NPDU
APDU
Control Bit in NPCI is changed to indicate Message contains Network
Layer message rather than APDU
 The above diagram shows encrypted APDU placed in a security
payload. Similarly we can do for NPDU. We can send Secured BVLL
message for encrypted NPDU.
 We can encrypt the message using HMAC, MD5 or SHA-256.
BACNET WEB SERVICES
 BACnet uses standard way to integrate Web- based application, i.e. using
XML, SOAP, WSDL, and UDDI open standards over Internet Protocol.
KEY DEFINITIONS & TERMINOLOGY
 BBMD: BACnet Broadcast Management Device
 Used to manage transmissions between networks
 NPDU: Network Layer Protocol Data Unit
 Specially formatted message that a BACNet device transmits over its physical link to
route the information correctly
 APDU: Application Layer Protocol Data Unit
 EPICS: Electronic Protocol Implementation Conformance Statement
 Link to downloadable template: http://www.bacnet.org/DL-Docs/135-2008-ANNEX-
A-rev-2010-11-02.doc
 BIBB: BACNet Interoperability Building Blocks