Configuration Management for Transportation Management Systems
Handbook

Chapter 1 – Introduction to Configuration Management and Transportation Management Systems

What is Configuration Management?

There are two fundamental purposes of configuration management (CM):

1. Establish system integrity
2. Maintain system integrity

To an individual who designs, develops, operates, or maintains complex transportation management systems (TMSs), the definition of integrity is well understood:

• A system with integrity is one in which all components are well defined and documented.
• A system with integrity is one in which a working baseline is always available to implement and provide transportation management services.
• A system with integrity is one that can be readily integrated with other regional intelligent transportation systems (ITS).
• A system with integrity is one with a high degree of traceability – allowing one to easily identify how system functions are provided technically.

In other words, a system with integrity is one that is available and functional.

Of course, establishing and maintaining system integrity does not just happen – it takes real, sustained effort. CM describes a series of processes and procedures developed in the information technology community to establish and maintain system integrity. It is an integral part of the systems engineering process. While some of the terms used in CM may be unfamiliar to transportation professionals, the core concepts and practices of CM are not technically complex. Rather, they represent sound practices in developing and maintaining any system. As you will see in this handbook, CM makes sense for use in transportation management systems.

Handbook Purpose

Configuration Management for Transportation Management Systems is intended to provide guidance for transportation professionals who are either (a) seeking to improve change management in a traffic management system or regionally integrated intelligent transportation system by introducing formal CM or (b) using CM currently and require a technical reference to support their activities.

Intended Audience

Configuration Management for Transportation Management Systems is intended to be guidance material for any individual who is engaged with or responsible for the planning, design, implementation, management, operation, or maintenance of transportation management systems. The handbook includes technically detailed information and examples suitable for individuals directly responsible for a CM program – such as staff engineers, consultants, maintenance personnel, and designers. In addition, the handbook provides high-level information that is well suited for agency management and policy makers.

The handbook also is intended to support individuals with varying levels of experience and involvement with CM. First, CM novices can use the handbook to gain an introductory understanding of the CM. Second, the handbook is intended to support individuals with a range of experience in CM by providing in-depth information and concrete transportation examples.

How the Handbook Was Developed

Transportation professionals participating in the Transportation Management Center Pooled Fund Study (TMC PFS) program initiated and guided the development of this handbook. The development team, led by the University of Virginia's Center for Transportation Studies, examined technical literature and standards in-depth, and interviewed and consulted with transportation professionals experienced with configuration management. Drafts of the handbook have been carefully reviewed on numerous occasions by a TMC PFS oversight committee.

Fundamentals of Configuration Management

Introduction to CM

"Configuration Management, applied over the life cycle of a system, provides visibility and control of its performance, functional and physical attributes. Configuration Management verifies that a system performs as intended, and is identified and documented in sufficient detail to support its projected life cycle…The Configuration Management process facilitates orderly management of system information and system changes for such beneficial purposes as to revise capability; improve performance, reliability, or maintainability; extend life; reduce cost; reduce risk and liability; or correct defects. The relatively minimal cost of implementing Configuration Management is returned many fold in cost avoidance. The lack of Configuration Management, or its ineffectual implementation, can be very expensive and sometimes can have such catastrophic consequences as failure of equipment or loss of life."

- EIA Standard 649

CM provides a holistic approach for effectively controlling system change. It helps to verify that changes to subsystems are considered in terms of the entire system, minimizing adverse effects. Changes to the system are proposed, evaluated, and implemented using a standardized, systematic approach that ensures consistency. All proposed changes are evaluated in terms of their anticipated impact on the entire system. CM also verifies that changes are carried out as prescribed and that documentation of items and systems reflects their true configuration. A complete CM program includes provisions for the storing, tracking, and updating of all system information on a component, subsystem, and system basis.

Benefits of CM

There are many reasons that personnel involved with TMSs should be interested in CM. As TMSs are becoming more sophisticated through the addition of new subsystems, integration with other systems, and overall physical expansion, the need to control the rapid pace of change has become apparent.

One problem that has been discovered as these systems change is that groups within an agency often work independently of each other, conducting changes without consulting one another and documenting the changes improperly. If the entire system is to undergo a major change or upgrade, this can present a significant problem. Contractors or agency personnel often will have to devote significant effort to retracing the steps taken for minor changes to the system to understand the current status. Doing so obviously requires major outlays of time and money. CM provides a methodology for identifying, tracking changes to, updating information on, and verifying the status of all items within a system. This provides TMS managers with an up-to-date baseline of their system, which is better understood and better prepared for further change, than a system that does not use CM.

A proper CM program will ensure that documentation (requirements, design, test, and acceptance documentation) for items is accurate and consistent with the actual physical design of the item. In many cases, without CM, the documentation exists but is not consistent with the item itself. For this reason, contractors and agency staff will frequently be forced to develop documentation reflecting the actual status of the item before they can proceed with a change. This "reverse-engineering" process is wasteful in terms of human and other resources and can be minimized or eliminated using CM.

Some of the other benefits of CM, which hopefully will never be needed, are its provisions for disaster recovery. Because a CM program should ensure that an accurate, up-to-date baseline of the system exists, the re-engineering process should be far less costly. Without CM and the associated baselining process, entire subsystems would require redesign at a much higher cost, and the recovery process would be greatly lengthened, if even feasible.

Another benefit of CM is that it provides for administration of change decisions with a system-wide perspective in mind. The configuration control board (CCB) has personnel with various areas of focus and from various departments within an agency. All proposed changes to the system are considered by the CCB in terms of the system, not just particular subsystems. Using tracking tools, unapproved changes can be detected and fixed more easily. As cited by one source for this handbook, CM also makes it easier to determine contractor error or negligence in making a change because of the tracking capabilities that a robust CM program and CM tool can provide.

In cases of subsystem or system development, CM allows TMS management to track requirements throughout the life cycle through acceptance and operations and maintenance. As changes are inevitably made to the requirements and design, they must be approved and documented, creating an accurate record of the status of the system. The CM process may be (and ideally should be) applied throughout the system life cycle.

Brief Introduction to CM Activities and Concepts

This subsection presents a brief introduction to CM activities and concepts. Please note that chapter 3 of Configuration Management for Transportation Management Systems discusses each of the following CM processes in detail.

The general CM process is described graphically in figure 1.1. Following this figure, each element of the process is described, and the benefits of the element are discussed.

CM Plan

While not shown in figure 1.1, a CM plan is integral to the process. The CM plan is the document that will guide the CM program of a particular group. Typical contents of a plan include items such as:

• Personnel.
• Responsibilities.
• Resources.
• Training requirements.
• Administrative meeting guidelines.
• Definition of procedures.
• Tools/tool use.
• Organization configuration item (CI) activities.
• Baselining.
• Configuration control.
• Configuration status accounting.
• Naming conventions.
• Audits and Reviews.
• Subcontractor or vendor CM requirements.

Plans typically are established at the outset of the CM program and undergo changes as the system evolves and as areas where the plan can be improved are identified. Contractors, in conjunction with the particular agency that will be using the CM program, often develop the plans.

The benefit of the CM plan is that it provides a central location for all CM program information. The items selected for CI depend upon the scope of the effort. For example, CI may be constrained to software items or may be larger and include system level components ranging from software, hardware, firmware, documentation, and perhaps the CM plan. The plan serves as the primary resource for any questions pertaining to the CM program. The primary benefit of the plan is that it clearly outlines how the CM program is to be executed and will leave as little room for ambiguity as possible.

Configuration Identification

Configuration identification is the process of documenting and labeling the items in the system. Depending on the scale of the particular CM program, this simply may involve software versions or, in the case of a large program, all hardware, software, documentation, and the CM plan itself. The goal of configuration identification is to provide a unique identifier for each item to help track the changes to that item and to be able to understand its place in the system. Often, identification involves recording the identifier, maintenance history, relevant documents and other information that will simplify the change process in the future.

The benefits of configuration identification are to provide a means of unique identification of system components to support traceability and change management processes. Proper identification minimizes confusion over various versions of configuration items and facilitates the change control process by allowing items to be more easily tracked as they undergo change.

Change Control

Change control is the process of assessing the impact of a possible change to a system, determining the fate of the proposed change, executing the approved changes, and ensuring that the change is carried through to the proper documentation. Usually, a change is proposed by someone who is working with the particular part of the system that will be changed. Change requests are submitted to the relevant administrative body for review. This body is normally referred to as a change control board (CCB). The CCB will review the proposed change, determine its effect on the overall system and decide whether or not to proceed with it. An important part of change control is ensuring that the change itself is documented and that the relevant configuration item's (CI) documentation now reflects that change.

The primary benefit of an effective change control procedure is that proposed changes are evaluated in terms of their impact on the entire system. Change control allows the changes to be reviewed by personnel with a variety of interests and areas of specialty. This minimizes the negative impacts of changes on other components of the system. Change control also ensures that the changes are properly implemented and within schedule and cost constraints.

Configuration Status Accounting

Configuration status accounting (CSA) is the process of ensuring that all of the relevant information about an item – documentation and change history – is up to date and as detailed as necessary. A primary goal of CSA is to repose CI information necessary to support existing and future change control efforts. A typical CSA system involves establishing and maintaining documentation for the entire life cycle of an object. Status Accounting is ideally carried out in conjunction with change control.

The primary benefit of CSA is that it provides a methodology for updating all relevant documentation to ensure that the most current configuration is reflected in the configuration identification database. CSA accounts for the current status of all proposed and approved changes. The goal of CSA is to provide decision makers with the most up-to-date information possible. Having the most recent information about a CI or changes implemented for a CI helps to reduce research efforts in future change control activities whether implementing a new change or rolling back a change that had a negative or unexpected impact.

Configuration Audits

Configuration verification and audit is the process of analyzing configuration items and their respective documentation to ensure that the documentation reflects the current situation. Essentially, while change control ensures that change is being carried out in adherence with the CM plan, configuration audits ensure that the change was appropriately carried out. The most important goal of this process is to prevent lost time on future changes due to inaccurate documentation. If discrepancies are located between the documentation and the item, the personnel carrying out the audit will prescribe a course of action for remedying the problem.

The most important benefits of configuration audits are that they verify that changes were carried out as approved by the relevant administrative body and that documentation about an item reflects the current configuration. By ensuring that changes are properly executed and all documentation is updated, configuration audits will facilitate future changes to the system.

Resources

A number of resources that support configuration management programs are available to transportation professionals. This section describes key resources that supplement this report. Furthermore, a comprehensive bibliography on the topic of configuration management is included in appendix B, which allows readers to locate more specific resources.

This handbook was written to supplement the "general" configuration management standard, EIA 649, from a transportation perspective. This standard is introduced below. Furthermore, the Military Handbook, Configuration Management Guidance (MIL-HDBK-61), also provides an excellent general overview of the configuration management process.

Companion Document - EIA Standard 649

As stated earlier, the processes and procedures of CM have been developing in the information technology community for many years. Therefore, this handbook makes use of a standard developed and refined in this industry – the Electronic Industries Alliance (EIA) Standard 649 National Consensus Standard for Configuration Management (ANSI/EIA-649/-1998) – which will be referred to from this point forward as EIA 649. EIA 649 is the definitive standard for CM and provides an excellent introduction to the fundamentals of CM. This standard describes all of the important components of a CM program with guidelines and benefits of each. Thus, this handbook does not attempt to restate or modify EIA 649. Rather, it refers to sections of EIA 649 where appropriate and then relates the material directly to transportation management systems.

Readers seeking detailed technical information are highly recommended to obtain a copy of EIA 649. At the time this handbook was printed, the standard could be obtained from EIA on line (www.eia.org [Link is no longer active]) for a price of $92. Those seeking general information regarding CM also are advised to obtain a copy of EIA 649; however, it is not absolutely necessary.

A brief description and summary of EIA 649 is presented in appendix A.

Transportation-Specific Resources

Besides this handbook, other transportation specific resources exist. These are summarized below.

• A Guide to Configuration Management for Intelligent Transportation Systems (FHWA-OP-02-048), published by the Federal Highway Administration, provides a high-level introduction to configuration management from a transportation perspective, and it serves as a sound introductory resource for individuals seeking to learn about configuration management.
• Configuration Management for Transportation Management Systems supplementary materials have been developed to support this handbook. These materials include a condensed "Primer," a 30-minute annotated presentation, a fact-sheet, and tri-fold brochure. These documents are especially well-suited to providing a general overview of the role and benefits of configuration management in a transportation management system application.
• National Highway Institute Course on Configuration Management has been developed to provide training tailored for transportation professionals.

How to Use This Handbook

It is intended that users of this handbook will be able either (a) to read it in its entirety as a comprehensive introduction to CM and its application in transportation management systems or (b) to use the handbook for ongoing support of a CM program by referring to individual sections on a stand-alone basis. Each chapter is structured in the same basic format. First, a general description and discussion of the chapter topic is presented. Next, specific guidance is presented concerning the application of the chapter's topic to transportation management systems. Lastly, detailed examples of the chapter's topic as used in existing transportation management systems are provided.

This handbook is structured in three key sections, as follows.

Section 1 – General Introduction to CM & Transportation Management Systems

This section provides general information describing CM and presents an overview of the current practices in CM and transportation management systems. As such, this section is well suited as an introduction to those new to this area or management personnel. The following chapters form section 1.

• Chapter 1. Introduction
• Chapter 2. Configuration Management and Transportation Management Systems – Current Practices

Section 2 – Technical Guidance – CM & Transportation Management Systems

This section provides detailed information on how to implement CM in transportation management systems. It is intended for a technical audience of individuals who are responsible for implementing a CM program. The following chapters form section 2.

• Chapter 3. Configuration Management Processes
• Chapter 4. Configuration Management Plan
• Chapter 5. Configuration Management Baselines

Section 3 – Guidance for Implementing a CM Program

The purpose of this section is to provide guidance to help transportation professionals implement or improve a CM program to support a transportation management system. This section goes beyond the technical details of CM to consider such issues as resources required to sustain a CM program, tools available to support CM, and so forth. This chapter provides material appropriate for both technical personnel and management to consider in framing an agency's program. The following chapters form section 3.

• Chapter 6. Configuration Management Program – Making it Work in Your Agency
• Chapter 7. Configuration Management and the System Life Cycle
• Chapter 8. Configuration Management Tools
• Chapter 9. Resources to Support Configuration Management Programs

Finally, the handbook concludes in chapter 10 with a presentation and discussion of nine guiding principles for CM and transportation management systems.

Usage Scenarios

As stated earlier, this handbook is intended to serve individuals with a variety of backgrounds and goals. Table 1.1 provides guidance for particular "types" of users.