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National Transportation Communications for ITS Protocol
National Transportation Communications for ITS Protocol
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National Architecture & NTCIP
NTCIP Center-to-Field
NTCIP Center-to-Center
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Message Set Standards Message
Communications Standards
DataDataElementElement
DataDataElementElement
DataDataElementElement
Data Element Standards
DataDataElementElement
ITS
Stan
dard
s Pe
rspe
ctiv
e
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Data Elements Standards
1. Traffic Management Data Dictionary (TMDD)2. NTCIP- Data Dictionary for Each Device3. TCIP- Data Dictionary for each Transit Application
1. Traffic Management Data Dictionary (TMDD)2. NTCIP- Data Dictionary for Each Device3. TCIP- Data Dictionary for each Transit Application
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Message Sets Standards
4. Message Sets for External TMC Communications (MS/ETMCC)5. Message Sets for Incident Management
4. Message Sets for External TMC Communications (MS/ETMCC)5. Message Sets for Incident Management
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Communications Protocol Standards
6. Center to Field Communications Protocols
7. Center to Center Communications Protocols
DATEX-ASN ; CORBA
6. Center to Field Communications Protocols
7. Center to Center Communications Protocols
DATEX-ASN ; CORBA
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• Message Set Standards• External TMC (ITE)• Incident
management (IEEE)• ATIS (SAE)
ITS Derived Standards
Message
DataDataElementElement
DataDataElementElement
DataDataElementElement
• Data Element Standards • TMDD (ITE)• NTCIP (AASHTO, ITE,
NEMA)• Object definitions
for traffic signals,message signs,transit (a.k.a. TCIP)
• ATIS (SAE)
• Communications Standards• IP, HDLC
framing (NTCIP effort)
• DSRC (ASTM)
• NTCIP Class B (NTCIP)
TMCTMC
Center, roadside, traveler, vehicle subsystems
DataDataElementElement
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Message Set Standards
Data Element Standards
Communications Standards
• TMDD Section 3 - Traffic Control • NTCIP NEMA TS 3.4 - Global• NTCIP NEMA TS 3.5 - ASC
• Message Sets for External Traffic Management Center Communications (MS/ETMC2)
Traffic ControllerStandards
Topics
• Class B• SP-PPP• TP-Internet• AP-STMF
Class D Profile
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Message Set Standards
Data Element Standards
Communications Standards
• TMDD Section 3 - Traffic Control • NTCIP NEMA TS 3.4 - Global• NTCIP NEMA TS 3.6 - DMS
• Message Sets for External Traffic Management Center Communications (MS/ETMC2)
DMSStandards
Topics
• SP-PPP• TP-Internet• AP-STMF
Class D Profile
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Building Blocks From
International Standards OrganizationISO
– Language to Define Data Elements : ASN.1
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Building Blocks From The Internet Authority
2. Rules ( Protocols) to Transport Data Elements
– SNMP, TCP/IP, UDP etc.
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Open System Interconnect- Reference Model OSI-RM
Each layer independently performs a specific task
Application
Session
Transport
Physical
LinkNetwork
Presentationmessage data stream
bits
data frames
segments
dialog connection
API
network address packets
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Off-the-Shelf Protocols Examples
Application
SessionTransport
Physical
LinkNetwork
PresentationSNMP
RS 232
PPP
UDP
IP
HDLC
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First NTCIP Objective is:
Develop Data Dictionaries &
Communications Protocols
System
USER Work Station
Communications Profiles
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System
Second NTCIP Objective is:Develop Communications Protocols for Center to Center Information Exchange
System
CommunicationsProtocols
1628
Devices2
dynObjDef1
dynObjData2
protocols1
layers1
profiles2
dynObjMgmt3
Class B1
rs232Async2rs232
1hdlc
3
snmp5
trans4
system6
asc1
ramp2
dms3
camera4
sensors5
global6
NEMA1206
private3
transportation4
experimental 2
mgmt1
NTCIP Standards Organization1 2Protocols Dictionarie
s
Twisted Pair
UDPTCP
IP
Null
Subnetwork
Information
Transport Transport
Application
Information
Subnetwork
Dynamic ObjectsReference Model
Files Data Objects
ITS Message Sets
SLIP PPP PMPPFDDI EthernetATM
SONET V Series Modem FSK Modem
Plant Plant
*
* Not all Subnetwork / Plant combinations are feasible
NTCIP Standards Framework
Fiber Coax Telco Line Wireless
FTP TFTP SNMP STMPCORBA DATEX
Application
Center-to-Center Center-to-Field
ITS Data Model ITS Data Dictionary
Topic- 2 NTCIP Roadmap
An Analogy that
Describes the
“Mechanics of NTCIP”
NTCIP Roadmap Analogy
Cardiology
History Street Address
Completion of a medical history form that uses a dictionary of terms and mails the form to a medical professional for action.
#1 - Objects Are NTCIP Data Building Blocks
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phaseWalk OBJECT-TYPESYNTAX INTEGER (0..255)ACCESS read-writeSTATUS mandatoryDESCRIPTION "Phase Walk Parameter
in seconds (0-255 sec). This shall control the amount of time the Walk indication shall be displayed. "
::= { phaseEntry 8 }
Word
Def•i•ni•tion \ def- -nish- n\ n: a word or phrase expressing the essential nature of a person or thing.
e e
Definitions are structured with syllabic spelling, pronunciation, grammatical usage, definition, etc.
NTCIP data elements are defined
for transmission using ASN.1 structure and are called objects.
Object
NTCIP “Speak”Analogy
#2 - NTCIP Data are Hierarchically Organized
Alphabet
Organizes definitions in an alphabetical structure.
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Organizes objects in a hierarchicalstructure.
ISO Tree
A B C D E F G H A B C D E F G H I J K L M N O P I J K L M N O P Q R S T U V W Q R S T U V W
X Y ZX Y Z
ISO, 1
Organization, 3
ISO-CCITT, 2
Country, 16
USA, 640
Organization, 1
DOD, 6
Internet, 1
Private, 4
Enterprises, 1
NEMA, 1206
ROOT
NTCIP “Speak”Analogy
NTCIP “Speak”Analogy
#3 - Device Standards areSubject Matter Dictionaries
Collections of definitions in alphabetical structure for subjects.
Subject Matter Dictionaries
Collections of objects in hierarchical structure for subjects.
NTCIP Standards
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Dermatology
Psychiatry
Cardiology
TS 3.4TS 3.5TS 3.6TS 3.7
#4 - Object Subset Needed for Application
NTCIP “Speak”Analogy
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Words Needed for a Specific Use
Subset of a subject area for a specificpurpose. E.G., heart disease historyuses only some medical terms.
History
Cardiology
Management InformationBase (MIB) Module
MIB Module is a collection of objects for a specific application (agency specific).
MIB forSignals
in City “A”
#5 - Objects Are Written According To Procedures
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NTCIP “Speak”Analogy
A paper form might be the“device” on which we wouldwrite a heart disease history.
Filling In a Form
History1. Print all
responses.2. Use a no. 2
pencil.3. Answer parts
1 & 2 only.4. Write from top
to bottom, left to right.
SNMP is a set of rules for reading and writing MIB objects to a device.
Simple Network Management Protocol (SNMP)
SNMPgetsetget-nexttrap
MIB forSignals
in City “A”
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Example of Object: Number of Permanent Messages Parameter
Page 2-14 TS 3.6 dmsNumPermanentMsg OBJECT-TYPESYNTAX INTEGER(0...65535)ACCESS read-onlySTATUS mandatoryDESCRIPTION “Indicates the current number of Messages stored in non-volatile, non—chargeble
memory( e.g. EPROM). For CMS and BOS , this number is the diffent messages that can be assembled.”
::={dmsMessage 1}
Both values are encoded as a pairNote: OID is only a references to data, it is not IP address
OID location in the tree
1.3.6.1.4.1.1206.4.2.3.5.1
This is not a IP Address, only a IN number for data element
#6 - Objects Are Transmitted Using Rules
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NTCIP “Speak”Analogy
Mailing Rules
To transmit the heart history formto a doctor, a patient follows amailing system’s rules.
• US postal service rules.
Open System Interconnect (OSI)
OSI 7 layer reference model (OSI-RM) has rules for transportingand processing the information.
Data processing rules
Data transportrules
• Application• Presentation• Session
• Transport• Network
• Data Link• Physical Physical network rules
#7 - Physical Layer Defines Media7
NTCIP “Speak”Analogy
The heart disease history infocould be submitted on paper,on a disk, on a voice tape, etc.
Media Choice
?History
Defines how to get the bits across the connection (copper, fiberoptic, coaxial).
Physical Media Choices
EthernetSonet
#8 - Data Link Layer DefinesData Packages
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NTCIP “Speak”Analogy
Specifies the packaging rules used to transmit the information.
Street Address
Packaging
History
Describes the data package transmitted over a single link & checks for errors.
High Level Data Link Control (HDLC) Frames
MIB forSignals
in City “A”
Flag Address Control
Info
FCS Flag
#9 - Network & Transport Layers Define Data Addressing and Delivery
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NTCIP “Speak”Analogy
Internet Protocol (IP)
Network layer routes through interconnected network links using Internet compatible rules.
Flag
Address
Control
IPI
Info FCS Flag
User Datagram Protocol (UDP)Transmission Control Protocol (TCP)Internet Protocol (IP)
Addresses the mail. Names the person at the address & repackages into smaller packages if needed.
Add Recipient Name
User Name
AddressAddress
Address
Return ReceiptRequiredTown, State,Zip,
Country
#10 - Top 3 Layers PerformData Processing
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NTCIP “Speak”Analogy
Read the heart disease history form and provide info for physician to act.
Reading the Form
History SNMPgetsetget-nexttrap
SNMP reads & writes MIB objects that have been transmitted using OSI-RM.
Simple Network Management Protocol (SNMP)
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Roadmap Summary - The Data
• Data elements are called objects and defined using a structure called ASN.1.
• Dictionaries of objects for specific applications are arranged by an ISO hierarchy instead of by alphabet.
• The subset of objects needed by an agency is collected into a database called a MIB.
• The procedure for reading and writing this database is termed SNMP. A more efficient version called STMP is applicable in many transportation applications.
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Roadmap Summary - Moving the Data
• The rules for transmitting the data follow the OSI reference model.
• Data is “packaged” into HDLC frames.• Data packages are moved through communications
networks using rules compatible with the Internet Protocols.
Topic-3 Center to Field (Device Level) Communications Profiles
Twisted Pair
UDPTCP
IP
Null
Subnetwork
Information
Transport Transport
Application
Information
Subnetwork
Dynamic ObjectsReference Model
Files Data Objects
ITS Message Sets
SLIP PPP PMPPFDDI EthernetATM
SONET V Series Modem FSK Modem
Plant Plant
*
* Not all Subnetwork / Plant combinations are feasible
NTCIP Standards Framework
Fiber Coax Telco Line Wireless
FTP TFTP SNMP STMPCORBA DATEX
Application
Center-to-Center Center-to-Field
ITS Data Model ITS Data Dictionary
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NTCIP Overview
SNMP Objects Dynamic Obj’s
STMP
IP NULL
PMPP PPP
FSK
RS-232
UDP
SNMP
Cable Air
Phone TWP
RS-232
Modem Radio
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Use of Existing Standards
• Why does the NTCIP re-define all of these standards?– There are unique requirements within the
transportation environment• There are options that are not appropriate for our
environment• There are features that our environment requires that are
not defined in existing standards
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ISO - NTCIP Relationship
Application
Presentation
Session
Transport
Network
Data Link
Physical
Information Level
Application Level
Transport Level
Subnetwork Level
Class Level
Plant Level
ISO NTCIP
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Profiles
• A standard that further restricts the interpretation/use of other standards
• May specify how to combine multiple standards together into a standard package
• Primarily developed to promote interoperable implementations
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Historic Class Profiles
Class B Class A Class CApplication STMF STMF STMFTransport Null UDP/IP TCP/IP
HDLC HDLC HDLCRS232 RS232 RS232
Subnet
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Subnet Profiles
• Defines how data is physically transmitted across a link, including– Physical signals– Addressing– Bit error checking– Permission to speak– Multiplexing of Transport Profiles
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Subnet Profiles
• PMPP232—low-speed, multi-drop via 232• Others Under Development
– Near-Term• PMPP/FSK—Low-speed, multi-drop, over twisted pair• PPP—Dial-up• Ethernet—LANs and other Ethernet systems
– Long Term• FDDI—Fiber systems• SONET—Another fiber option• Metropolitan Area Networks—Equivalent to a LAN
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Transport Profiles
• Routing across a network– Logical to physical address mapping– Delivery times– Error handling
• Fragmentation and re-assembly• Multiplexing of Application Profiles
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Transport Profiles
• Transportation (Null)—Low-speed connections• Internet—Computer industry standard
– UDP/IP– TCP/IP
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Application Profiles
• Defines structure for information exchange– Overall structure of each message– What information gets exchanged– Under what conditions can information be
exchanged– Byte-level encoding formats
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Application Profiles
• Field Communications– SNMP—Computer industry standard– STMP—Low-speed, high data exchange req’ts
• Center-to-Center Communications– DATEX-ASN—Simple structured solution based on messages– CORBA—Advanced object-oriented solution
• General Use– FTP—Standard file transfer– TFTP—Simple file transfer where TCP not available or
frequent transfers