日本智能交通系统架构
System Architecture for ITS in JAPAN
November, 1999
National Police Agency
Ministry of International Trade and Industry
Ministry of Transport
Ministry of Posts and Telecommunications
Ministry of Construction
Preface
Modern society is becoming increasingly information-oriented at the global level, and the road traffic is no exception. Also in Japan, the use of information technologies on roads, traffic and vehicles are being promoted in order to solve such problems as traffic accidents, congestion and the environmental deterioration , as well as to meet the market-expansion needs of the automobile industry, the information and communication industry and other industries.
To promote the use of information technologies on roads, traffic and vehicles, the five related government bodies (National Police Agency, Ministry of International Trade and Industry, Ministry of Transport, Ministry of Posts and Telecommunications, and Ministry of Construction) jointly finalized a "Comprehensive Plan for ITS in Japan" in July, 1996, which is based on the "Basic Guidelines for the Promotion of an Advanced Information and Telecommunications Society" (determined by the Advanced Information and Telecommunications Society Promotion Headquarters in February, 1996). They also demonstrated a long-term vision of basic ideas on ITS development, implementation and User Services in which ITS will be promoted systematically and efficiently from the users' view point, and promoted in Japan based on the Comprehensive Plan in cooperation with industrial and academic sectors.
Given this history, the practical use and R&D of each specific system of ITS have been further accelerated in recent years in Japan. At the same time, the five government bodies recognized the need to create a grand design which was more detailed than the long-term vision in order to efficiently realize an integrated, highly expandable ITS system to respond to changes in social needs and development in technology in the future. In August 1999, the five government bodies organized a draft copy entitled “System Architecture for ITS.” Subsequently, the draft was released so as to collect opinions from a broad range of the industrial and academic sectors and to actively address information overseas.
Recently “System Architecture for ITS” has been composed.
It is our hope to continue promoting ITS-related projects through extensive cooperation among the five government bodies with the industrial and academic sectors as well as other nations targeting an early and efficient realization of diverse ITS services based on the comprehensive plan and System Architecture.
November 5, 1999
National Police Agency
Ministry of International Trade and Industry
Ministry of Transport
Ministry of Posts and Telecommunications
Ministry of Construction
Contents
Volume I Guidelines for Constructing the System Architecture Chapter 1 Background of Constructing the System Architecture
1.1 What is System Architecture?
1.2 History and Current Situation of ITS in Japan
1.3 International Trends Related to System Architecture
1.4 Necessities for Constructing the System Architecture
Chapter 2 Concept for Constructing the System Architecture
2.1 Purpose of Constructing the System Architecture
2.2 Concept for Constructing the System Architecture
Volume II Achievements of Constructing the System Architecture Chapter 1 Achievements of Constructing the System Architecture
1.1 Varieties of Achievements of Constructing the System
Architecture
1.2 Characteristics of the System Architecture
1.3 Ideas for Achieving Characteristics
Chapter 2 Detailed Definition of User Services
2.1 What is Detailed Definition of User Services?
2.2 Structure of ITS User Services
Chapter 3 Constructing the Logical Architecture
3.1 What is Logical Architecture?
3.2 Achievements of Constructing the Logical Architecture Chapter 4 Constructing the Physical Architecture
4.1 What is Physical Architecture?
4.2 Achievements of Constructing the Physical Architecture Chapter 5 Standardization Candidate Areas
5.1 What are the Standardization Candidate Areas?
5.2 Evaluation of the Areas from the Viewpoint of Securing
Compatibility
Volume III Guidelines on Applying the System Architecture Chapter 1 Concept for Applying the System Architecture
1.1 Stages of Applying the System Architecture
1.2 How to Apply the System Architecture and Who it Applies to
Chapter 2 Actual Application of the System Architecture
2.1 Building a Common Awareness of ITS Reality
2.2 Establishing a Plan for Project Development and Implementation
2.3 Combination and Application of User Services to Achieve ITS
Policies
2.4 Design and Development of the Systems Concerning ITS
2.5 Promotion of Standardization Activities
2.6 Utilization of the Information in ITS Research
Appendix
Glossary of Terminology
Volume I Guidelines for Constructing the System Architecture
Contents
Chapter 1 Background of Constructing the System Architecture
1.1 What is System Architecture?
1.2 History and Current Situation of ITS in Japan
1.3International Trends Related to the System Architecture
1.4Necessities for Constructing the System Architecture
Chapter 2 Concept for Constructing the System Architecture
2.1 Purpose of Constructing the System Architecture
2.2 Concept for Constructing the System Architecture
Chapter1 Background of Constructing the System Architecture
1.1 What is System Architecture?
In the late 20th century, man started to conduct large-scale projects with advanced and diverse purposes. At the same time, we saw dramatic improvements in the element technologies essential to realizing such projects. The most significant ones are information processing technologies including computers, and the information and telecommunication technologies which achieved digital communications. By combining information processing technologies and information and telecommunication technologies, man built large-scale systems with advanced and diverse purposes.
Such large-scale systems are made possible by associating diverse technologies that compose the systems in many ways. Therefore, when building a system, it is important to create a common awareness of the overall image among the parties involved, and promote the efficient realization of an integrated system. When building a large-scale system that consists of diverse technologies, we usually organize a structure for the entire system in advance, and then develop specific systems conforming to the structure.
System Architecture is a structure for the entire system that illustrates component elements (technologies and specific systems) and their relation to each other. It is essential for designing and developing a system that works as a whole.
Fig. 1. 1-1 What is system architecture? (concept)
* System Architecture is
like a picture that shows
multiple elements of the
system and how they
relate to each other in the
frame as a system, and
provides an overall
picture of the system.
1.2 History and Current Situation of ITS in Japan
(1) History of Constructing the "Comprehensive Plan for ITS in Japan"
Japan, one of first countries in the world to take on R&D for the Intelligent Transport Systems (abbreviated ITS), inaugurated ITS work when the Ministry of International Trade and Industry started to develop CACS (Comprehensive Automobile traffic Control System) in 1973. Later, in the 1980s, the Ministry of Construction came out with RACS (Road/Automobile Communication System) and the National Police Agency with AMTICS (Advanced Mobile Traffic Information and Communication System), which led to VICS (Vehicle Information and Communication System) in cooperation with the Ministry of Posts and Communications which had been developing and standardizing radio wave systems. From the late 1980s to early 1990s, these government bodies promoted projects such as ARTS (Advanced Road Transportation Systems by the Ministry of Construction), SSVS (Super Smart Vehicle System by the Ministry of International Trade and Industry), ASV (Advanced Safety Vehicle by the Ministry of Transport), and UTMS (Universal Traffic Management Systems by the National Police Agency).
At the same time, the academic and industrial sectors organized the Vehicle, Road and Traffic Intelligence Society (abbreviated VERTIS), which worked closely with ITS America and ERTICO in various ITS-related activities including information exchanges with the secretariat of the World Congress on ITS and ITS-related organizations in North America and European countries. Private firms are also actively involved in forming ITS markets and launching products for the car navigation system that uses GPS based on digital road maps developed jointly by the government and the private sector.
Thus, Japan has been actively involved in the R&D of specific technologies that could become ITS core technologies. In the process, it became clear that since ITS would affect broad areas of road, traffic, vehicles and information and telecommunications, it would be necessary to work with people in various fields, promote ITS based on international exchanges, and provide User Services to meet their needs.
In February, 1995, the Advanced Information Telecommunications Society Promotion Headquarters headed by the Prime Minister determined the "Basic Guidelines for the Promotion of an Advanced Information and Telecommunications Society". And in August, 1995, the five related government bodies compiled the "Basic Government Guidelines for Advanced Information and Communications in the fields of Roads, Traffic and Vehicles," and started to apply those guidelines to development and practical issues such as selecting nine areas for ITS development as a basic ITS structure. In this climate, in July, 1996, the five government bodies compiled a "Comprehensive Plan for ITS in Japan" which is a long-term vision of ITS's goals regarding 20 User Services and development and implementation, so that the government bodies can maintain close ties with each other and promote ITS systematically and efficiently from the users' point of view.
(2) Towards the realization of ITS
While constructing the "Comprehensive Plan for ITS in Japan," Japan has seen active movement toward the practical use of specific systems such as VICS, ETC (Electronic Toll Collection System) and UTMS. The five government bodies have been involved in another ITS-related possibility focusing on local communities; to promote the ITS model regional experiment project by supporting model ITS regional experiments conducted by municipalities in cooperation with VERTIS, and sending out information on these examples to other municipalities in order to promote an ITS that is more closely tied to local communities.
At the same time, private firms launched products such as car navigation systems designed to receive information by cellular phone as well as other systems to maintain appropriate distance between cars by radar.
Thus, Japan has put some systems into practical use and accelerated other systems for practical use. However, there are difficulties in designing and developing specific systems effectively and efficiently such as a lack of the big picture of the large-scale system composed of diverse technologies, and unclear information and the necessary capacity to build a practical system based on the "Comprehensive Plan for ITS in Japan" which outlines 20 User Services.
1.3 International Trends Related to the System Architecture
(1) Trends in the U.S.A.
In America, the Department of Transportation (DOT) plays a major role. In September, 1993, DOT started a 33-month program to develop a System Architecture. In Phases I and II, several private sectors examined System Architecture designs before publishing the approximately 5000-page National System Architecture in the summer of 1996.
In the National System Architecture design, America not only promoted standardization activities, notification and PR activities based on the architecture, but also deployed actual systems and continues to maintain the National System Architecture.
As for the standardization activities, they presented 12 standardization requirements such as standardization of DSRC (Dedicated Short Range Communication) in the National System Architecture. Later in July, 1996, they published the ITS Five-Year Standardization Plan with a list of 44 priority standardization articles including communication rules between systems.
As for notification and PR activities, America not only actively publicizes its National System Architecture both in and outside of the country, but also continues to promote seminars for local governments and private firms. With the idea of making practical use of ITS within the structure of the National System Architecture in local regions, the DOT finalized "Building the ITI" in order to propose the launch of ITI (Intelligent Transportation Infrastructure) in January, 1996. Based on the MDI (Model Deployment Initiative) decided on in October, 1996, America is promoting the preparation of an ITS infrastructure based on the National System Architecture in the four metropolitan areas of Phoenix, Seattle, San Antonio, and New York/New Jersey/Connecticut.
The TEA-21 (Transportation Equity Act for the 21st Century), which controls the budget for domestic surface transportation, assigns subsidies for the deployment project of ITS on condition of preparing systems based on the National System Architecture.
Fig. 1.3-1System Architecture-Based ITS Promotion in America
(2) Trends in Europe
In Europe, the European Commission (EC) is in charge. As a task force of DRIVE II (Dedicated Road Infrastructure for Vehicle Safety in Europe II), whose purpose was to increase safety and transportation efficiency and to decrease the effects on the environment by improving infrastructure, they formed SATIN (System Architecture and Traffic Control Integration) in 1994 to examine methods to build a System Architecture related to road traffic.
After completing DRIVE II, the EC started T-TAP (Transport-Telematics Application Programme). One of its activities is CONVERGE, methods to examine System Architecture. They reformed the methods examined in SATIN, and added a method of System Architecture for railways, water transport, airways and other transportation besides road traffic after study and preparation.
Thus, the EC, which conducted R&D mainly on methods of building System Architecture, applied the research results of the methods to building a Pan-European System Architecture for KAREN (Keystone Architecture Required for European Networks).
Fig. 1.3-2 Flowchart of System Architecture examination in Europe
1.4 Necessities for Constructing the System Architecture
After formulated "The Comprehensive Plan for ITS in Japan," specific ITS, which is comprised of diverse specific systems, has been actively put into practical use or under preparation. Therefore, in order to build concrete systems based on "The Comprehensive Plan for ITS in Japan" which conformed to 20 User Services, it is necessary to clarify the position of each specific system in the entire ITS and to develop designs considering the necessities for each specific system in relation to the entire ITS as well as common areas shared among other specific systems and the timing of putting those systems into practical use. To achieve this, it will be necessary to promote an understanding of the entire ITS by ITS-related people in industry and academic sectors and all users, and to show them the systematic development of ITS.
At the same time, other countries, such as America, are strategically promoting ITS considering the future development of overall ITS by formulating System Architecture and applying it to ITS standardization activities, notification/PR activities, deployment and so forth.
Japan should also make ITS an integrated system, build it efficiently, and develop it as a highly expandable system that corresponds to future changes in social needs and development in technology.
Also, Japan’s original system architecture (framework) has to be constructed in order to realize, in the global expansion of ITS environment, the original User Services which respond to Japan’s own natural and social environment. Japan’s original System Architecture needs to be based on the clear recognition and distinction between parts that should be standardized to foreign System Architecture and parts that is peculiar to Japan.
Therefore, in order to secure system integration and systems-building efficiency in integration and building of the system during the process of promoting its actual building, it is necessary to consider the role of the specific systems in ITS when designing specific systems, share information and functions in the systems, and utilize such information and functions as a platform for developing systems. In order to secure system expandability, it is necessary to systematically organize information and functions in the systems, and make the interface and other elements in the systems interchangeable. Furthermore, it is also necessary to signify the system information and functions to be shared as Standardization Candidate Areas so as to effectively and efficiently participate in national and international standardization activities.
Now that Japan is striving to implement the service contents and basic concepts of the system presented in "The Comprehensive Plan for ITS in Japan" and acknowledges the necessity of System Architecture this commitment has been published in order to efficiently build integrated systems, secure expandability of systems, and assure promotion of national and international standardization activities.
Chapter2 Concept for Constructing the System Architecture
2.1 Purpose of Constructing the System Architecture
The purpose of constructing theSystem Architecture for ITS is: 1) to build an integrated system efficiently, 2) to secure expandability of the system, and 3) to promote national and international standardization.
By building an integrated system which makes the system compact, users will have diverse applications such as carrying the system wherever they go, and they will be less burdened by a system that can replace the operations and the judgment users used to make. Another advantage is that building an efficient ITS and sharing common information and functions can avoid duplicate investment. Thus, fair costs will be offered because a common infrastructure enables manufacturers to easily participate and to become multiple vendors of device supply.
At the same time, by securing expandability of the systems, it will be easier to alternate and add information and functions due to changes in social needs and development in technology, as well as toadd systems due to the increase of User Services and the expansion of user service areas.
Furthermore, by comparing currently promoted standardization tests to candidate areas of standardization, and by clarifying duplicates and areas not yet examined for standardization, it will help decide priorities in standardization work in standardization-related institutions. And it will be more realistic to efficiently build an integrated system in Japan and to secure expandability of the system in the process of global ITS development.
Thus, by constructing System Architecture to achieve the requirements of 1) to 3) and building a system based on it, it will be possible to promote ITS more efficiently and effectively. Another advantage is that building an efficient ITS and sharing common information and functions can avoid duplicate invest. Also, making a common infrastructure enables to secure the opportunities for the creation of new markets and participation of various size of businesses, and to offer fair costs involved in multiple vendors in instrument procurement.
2.2 Concept for Constructing the System Architecture
(1) Procedure of constructing the System Architecture
The procedure of constructing the System Architecture is: 1) to define the details of User Services, 2) to construct the Logical Architecture, 3) to construct the Physical Architecture, and 4) to prepare Standardization Candidate Areas.
The first to be implemented, "1) to define the details of User Services" means to define detail contents of User Services to be analyzed in constructing Logical Architecture. To be more concrete, we defined "purpose" and "contents" of Specific User Sub-services. In this definition, User Services were subdivided into 172 detailed Specific User Sub-services. Also, Specific User Services were established as median organizing units between User Services and Specific User Sub-services and ITS services are systemized into four ITS service levels including development. The System Architecture for ITS should be constructed based on defined detail Specific User Sub-services. That way, the System Architecture constructing Logical and Physical Architecture, which are prepared after examining the entire sub-services will not be in the user service category that is a structure of subsidizing services into sub-services.
The second to be implemented, "2) to construct the Logical Architecture", means to clarify information sent and received between users and systems and processed in the systems in order to offer each Specific User Sub-service; to take out "information" and "functions" while processing to systematize the "information," and to create a model of the relationship between the "functions" necessary to offer services and "information" processed in the function by using a common form.
"3) To construct the Physical Architecture" is to make a common combination of "functions" taken out in the Logical Architecture and "information" processed in the functions among Specific User Sub-services in order to integrate the entire system; to distribute those combinations to cars, roadside and centers in order to create a model of the entire system to realize ITS.
"4) To prepare Standardization Candidate Areas" is to place all of the 24 subsystems, one of the achievements of the Physical Architecture, and four communication systems in the areas (Standardization Candidate Areas) to be standardized. This process is shown in the subsystems interconnect diagram. The subsystems evaluated based on the "degree of sharing Specific User Sub-services" and the communication points used in the subsystems is summarized. Its goal is to support the priority decision-making of standardization activities by standardization-related institutions.
Fig. 2.2-1 Procedure of constructing the System Architecture for ITS
(2) Structure to compile system architecture
It was decided that the five government bodies would compile the System Architecture for ITS in cooperation with VERTIS. In the process, the construction work was inaugurated in January 1998 and the draft was organized in August 1999. Subsequently, the draft was released so as to collect opinions from a broad range of the industrial and academic sectors and to actively address information overseas, In November 1999, the process was completed as “System Architecture for ITS.”
The System Architecture for ITS will be revised occasionally in case the upper plans such as “Comprehensive Plan for ITS in Japan” is revised and conditions of ITS promotion changes, such as rapid progress in element technology related to ITS.
Fig. 2.2-2 Structure for constructing the System Architecture
Volume II Achievements of Constructing the System
Architecture
Contents
Chapter 1 Achievements of Constructing the System Architecture
1.1 Varieties of Achievements of Constructing the System
Architecture
1.2 Characteristics of the System Architecture
1.3 Ideas for Achieving Characteristics
Chapter 2 Detailed Definition of User Services
2.1 What is a Detailed Definition of User Services?
2.2 Structure of ITS User Services
Chapter 3 Constructing the Logical Architecture
3.1 What is the Logical Architecture?
3.2 Achievements of Constructing the Logical Architecture Chapter 4 Constructing the Physical Architecture
4.1 What is the Physical Architecture?
4.2 Achievements of Constructing the Physical Architecture Chapter 5 Standardization Candidate Areas
5.1 What are the Standardization Candidate Areas?
5.2 Evaluation of the Areas from the Viewpoint of Securing
Compatibility
Chapter1 Achievements of Constructing the System Architecture
1.1 Varieties of Achievements of Constructing the System Architecture
The achievements of constructing the System Architecture are composed of four sections: to define detailed User Services, to construct a Logical Architecture, to construct a Physical Architecture, and to organize Standardization Candidate Areas.
The three major achievements from the definition of detailed User Services are as follows: a "user service structure chart" which systematically describe Specific User Services and Specific User Sub-services under nine areas for development and 21 User Services; a "sub-service definition" which describes the "purpose" and "contents" of Specific User Sub-services, and a "definition sheet of sub-service details" which describes the capabilities necessary for realizing each Specific User Sub-service as well as target areas besides "sub-service definition."
The two major achievements of constructing a Logical Architecture are as follows: an "information model" which represents all the information processed in ITS as a layer-structure system, and a "control model" described in a common form, which represents the relationship between the "functions" necessary to offer services and the "information" processed in the functions.
The three major achievements of constructing a Physical Architecture are as follows: a "Physical Model for Each Specific User Sub-servicess" which clarifies the structure of systems offering Specific User Sub-services; a "Physical Model for the Entire System" which clarifies the entire system for realizing ITS; a "sub-systems diagram" which is prepared for the purpose of an overview of the structure of the entire system.
The major achievements of organizing Standardization Candidate Areas are: 24 subsystems and 4 communication points, shown in the Sub-Systems Interconnect Diagram, which is placed in the area to be standardized. The selected 11 sub-systems and one communication point that determine the priority of standardization activities in institutions related to standardization.
1.2 Characteristics of the System Architecture
In constructing a System Architecture, the following two points were emphasized: 1) securing flexibility to meet changes in social needs and development in technology; 2) securing compatibility and interconnectibility with an advanced information and telecommunication society.
(1) Securing flexibility to meet Changes in Social Needs and Technological
Development
Since ITS is a project which targets a wide range of roads, traffic, vehicles, information and telecommunication and others, it is possible only when the five government bodies cooporate as well as the industrial-academic sectors. It is expected that technological development in information and telecommunications and computer-related fields will be further accelerated. In the process of realizing ITS, it
is also expected that technological development will bring out new needs and that current user needs will change due to fundamental changes in society, environment and economy.
To secure flexibility to meet changes in social needs and technological development, efforts were made by programming System Architecture to maintain its original functions and also by partially changing/expanding System Architecture in the cace of future changes in social needs and development in technology.
(2) Secure compatibility and interconnectibility with an advanced information
and telecommunication society
"The Comprehensive Plan for ITS in Japan" presented the following two points: The Advanced Information and Telecommunication Society is an information-oriented society in many fields including ITS; and it is important to link ITS and many other information-oriented fields. Specifically, in order to realize an advanced information and telecommunication society, it is essential to prepare an information telecommunication infrastructure such as optical fibers, to make intelligent roads and vehicles which are terminals for receiving and transmitting information, and to improve information contents. We made it clear that, in promoting ITS, it is important to look over a wide range of areas which and the areas that need to integrate with ITS into the Advanced Information and Telecommunication Society, and to secure compatibility and interconnectibility in infrastructures not only within ITS areas but other areas to harmonize with ITS, terminals to receive and to transmit information and its contents.
In recent years in Japan, private firms offer users information in fields other than roads, traffic and vehicles through ITS-related services belonging to an area which needs to harmonize with ITS. Therefore, it is becoming increasingly necessary to secure compatibility and interconnectibility among different areas for the Advanced Information and Telecommunication Society and areas that need to harmonize with ITS. Given this background, we made efforts to secure compatibility and interconnectibility with an advanced information and telecommunication society in constructing System Architecture for ITS.
1.3 Ideas for Achieving Characteristics
(1) Ideas for securing flexibility to meet Changes in Social Needs and
Technological Development
The System Architecture for ITS adopted the object-oriented analysis method which makes it easy to alternate/expand some parts of the System Architecture. It allows to secure flexibility to meet future changes in social needs and development in technology and to occasionally revise the architecture to meet changes in ITS promotion situations.
A popular method of building a System Architecture used to be the "structured analysis method" which analyzes and structures the functions necessary for realizing services. This method has been quite effective in analyzing large-scale systems, and has the advantage of requiring a relatively short time to design a System Architecture. However, since the structured analysis method does not systematically organize information processed in the system, it requires an enormous effort to organize new functions and to specify the information used in them when the system is changed and/or expanded. It also requires the revision of many functions, making it troublesome to correct the system.
In the meantime, the development of software engineering evolved the "object-oriented analysis method" which unifies functions and information and describes a target system with "objects" making it possible to create a unified model of information and functions within a system. Since the object-oriented analysis method organizes and structures information based on its similarities, it makes it easier to identify information in the structure by discerning information characteristics and so forth that are to be added and/or interchanged even when some services are added and/or changed. In this analysis method, functions and information processed in them are treated as a unit. The function and its related information to be added and/or changed are instantly detected. By deploying these distinctive qualities, it enables one to find the parts that need to be corrected relatively quickly as well as minimizng corrections.
In constructing the System Architecture for ITS, we adopted the object-oriented analysis method to make it easier to meet future changes in social needs and development in technology.
As for the object-oriented analysis method, worldwide software engineering specialists have been developing different languages, and are now gradually standardizing them to a UML (Unified Modeling Language). Given this situation, we decided to use the UML for the ITS System Architecture. Incidentally, when discussing the standardization propositions given by member nations, the ISO/TC204 WG1 (System Architecture sub-committee) has been examining System Architecture as a common basis of discussion in order to clarify where the plan for the entire ITS system stands. In this examination, UML from the object-oriented analysis method, and real time structuring from the structured analysis method are proposed as different languages.