Center-to-Center Working Group

Contact:Manny Insignares, Consensus Systems Technologies Corporation

Standards Work Items:
This working group is responsible for development and maintenance of the following standards.

Number Title Status
1104 C2C Naming Convention Specification Jointly Approved
1105 NTCIP CORBA Security Service Specification User Comment Draft
1106 NTCIP CORBA Near Real-Time Data Service Specification Work Item, Approved
1601 CORBA Base Object Model for TMS User Comment Draft
1602 Generic Reference Model (GRM) for Traffic Management Working Group Draft
1603 CORBA-Specific Reference Model (CSRM) for Traffic Management Working Group Draft
2304 NTCIP AP-DATEX-ASN Recommended Standard
2305 NTCIP AP-CORBA User Comment Draft
2306 Application Profile for XML in ITS Center to Center Communications (AP-C2CXML) Jointly Approved
2500 NTCIP InP-C2C Withdrawn
2501 NTCIP InP-DATEX Work Item, Approved
2502 NTCIP InP-CORBA Work Item, Approved
9010 XML in ITS Center-to-Center Communications Working Group Draft

C2C Working Group Scope of Work: 
The Center to Center Protocol Working Group (WG) has the responsibility to develop transportation related protocols between centers. Centers include traffic management, transit management emegency management, traveler information (ISPs and event sources), airport information, and other related centers. Overall the Center to Center Protocol (C2C) is intended to connect transportation management centers in a wide area network to exchange coordination and management data.

Summary of Center-to-Center Working Group Working Group Activities: 
The 21st meeting of the NTCIP Center-to-Center Working Group was held at the offices of the National Electrical Manufacturers Association (NEMA) in Rosslyn, VA adjacent to Washington, D.C. on April 18-19, 2001. Key activities at the meeting include:

  • Review of user comments on NTCIP 2305 (Application Profile for CORBA)
  • Discussion of FHWA priorities and plans for expediting key standards
  • Review of revised Near-Real-Time Data Service specification
  • Review of use cases for communications with traffic signal systems
  • The working group agreed to use Rational Rose 2000 as the modeling tool and to follow the format of ISO 17383 – Data Dictionary for Traffic Management Centers
  • The working group recommended that the proposed project to upgrade the Message Sets for External TMC Communications include documentation of high-level generic sequence diagrams that could form the basis of a consistent dialog structure for all protocols

The WG developed a CORBA road map (in the September, 2000 meeting) that identifies the following items as high priority for further standards development.

  1. Base objects for the following functional areas:
    • Operations Center
    • Detector Data Collection
    • Traffic Signal Controller
    • Dynamic Message Signs
    • CCTV
    • Ramp Meters
    • Events/Incidents
    • Vehicles
    • Link/Node model
    • HAR/HAT
    • Environmental Sensors
  2. General services in the following areas to insure commonality of usage between all the base objects:
    • Location (using LRMS profiles)
    • Identification (in progress)
    • Security/access control (in progress)
    • Object publication standards (usage of naming, trader services, etc.)
    • Date/time (using CORBA type)
    • Common services (usage of notification services, etc.)

The base objects for each functional area should be diagramed in UML notation in addition to textual description. Each document should contain (at least) Use Cases, Sequence Diagrams, Class Diagrams, and IDL (these will be documented in the two new standards listed in the Standards Table below).C2C Working Group Task Schedule: 
July 25-26, 2001 Working Group to meet in Denver, CO
October 25-26, 2001 Working Group to meet in Phoenix, AZ

C2C Working Group Issues: 
The following key issues are currenlty being addressed by the WG:

  • CORBA object models need to be defined (a road map was developed to help with this)
  • Standardized Dialogues need to be defined
  • Submittal of NTCIP 2305 to the NTCIP Joint Committee for balloting as a recommended standard, will be delayed until all potential changes related to the current object modeling and base services have been identified
  • Resolve the need for a CORBA Near Real-time Data Services standard

Projects Now Implementing NTCIP C2C Standards: 
The following projects are currenlty implementing or have implemented either CORBA or DATEX-ASN as the Center to Center standard:

  • DATEX-ASN and the ATIS message set for a link between an ATIS data fusion system and a roadway information source system in the Hampton Roads region in southeast Virginia
  • TravelTip CORBA network in Orange County in southern California will start up in June, 2000. Initially it will link three local traffic management systems (Mission Viejo, Tustin, Orange) to the traveler information server. Fifteen centers are planned to link to the ATIS system eventually.
  • Washington (state) DOT has initiated a project to link the State traffic signal management system to local city traffic signal systems, initially using DATEX, but with an eye to also providing a CORBA interface in the future. The first city targeted for connection is Bellevue.
  • DATEX-ASN in Dallas, Texas for use in traffic managment between multiple centers
  • TransCom in New York has implemented a DATEX-ASN traffic management implementation and have tested the network loading to capacity

The C2C Working Group is Responsible for Developing and Interfacing with the Following Documents: 

Number Title Assigned/Status
NTCIP 2500 NTCIP Information Profile for Center to Center (InP-C2C) Not yet assigned, this document is proposed but not yet being worked on.
NTCIP 2501 NTCIP Information Profile for DATEX-ASN (InP-DATEX) Version 1.01 is now available.
NTCIP 2502 NTCIP Information Profile for CORBA (InP-CORBA) Currently known as EP-CORBA and is being updated from 2/10/99 version.
NTCIP 2304 NTCIP Application Profile for DATEX-ASN (AP-DATEX) Recommended Standard, version 1.06 available.
NTCIP 2305 NTCIP Application Profile for CORBA (AP-CORBA) Released to Joint Committee as a User Comment Draft, version 1.11 available.
TBD Center to Center Guide Document (C2C-Guide) J. Brummond, WG User Comment Draft, dated 19 April 2000.
NTCIP 8003 NTCIP Framework and Classification of Profile Approved by Joint Committee.
ISO 14827-1 Transportation Information and Control Systems – Data Exchanges Between Traffic Management and Information Centers – Part 1:Message Definition Requirements K. Vaughn, TC204 Committee Recommended Standard.
ISO 14827-2 Transportation Information and Control Systems – Data Exchanges Between Traffic Management and Information Centers – Part 2:DATEX-ASN K. Vaughn, TC204 Committee Recommended Standard.
NTCIP 1104 Naming Convention Specification Working Group Draft version 01.03
NTCIP 1105 CORBA Security Services Specification Working Group Draft Version 0.01
NTCIP 1106 CORBA Near Real-Time Data Services (NRTDS) Working Group Draft version 0.05
TBD General Objects & Services Not yet assigned, Proposed
TBD Transportation Management Domain Objects Not yet assigned, Proposed