8. Implementation and Deployment
Integration is an iterative process, taking hardware and software components and forming them into complete sub-system elements, and then taking the sub-systems and combining them into larger sub-systems or systems until all the subsystems and network systems are combined into a complete and functioning ICMS. This process consists of several system engineering stages as shown on the right side of the "V" diagram. Integral to these system integration activities are system verification and validation processes:
- Verification. Ensuring that all functions implemented in the ICMS have been implemented correctly (i.e., "building the system right").
- Validation. Ensuring that the desired functions have been implemented in the delivered ICMS (i.e., "building the right system").
There is a relationship between the activities performed on the left side of the "V" (operational concepts, requirements, designs) and the integration and verification activities on the right side. Each stage of integration is tested and verified against the left side of the "V" through verification plans. For example, the "System Requirements" stage is directly across from the "System Verification" phase. Thus, the various system acceptance tests ensure that the required system functionality, as documented in the ICMS requirements document and traceability matrix, is being satisfied.
A complex ICMS effort may need a written integration plan. This plan, which should be viewed as an extension of the SEMP/Project Plan, documents the process for integrating the ICMS, including:
- Sequence in which the various components of the system should be integrated.
- Resources, schedule, and coordination activities that are required.
- Product (implementing a related set of functionality) resulting from each integration step.
Hardware/Software Development
This step involves the fabrication and construction of hardware, the coding and development of software, and the procurement and configuration of COTS products in accordance with the requirements and detailed design documentation. Quality control is an essential element of this stage, including software engineering and code development standards (e.g., ISO 9000) and walk-throughs of developed programs where programmers review the work of another programmer to determine whether any errors exist.
Unit, Subsystem, and System Testing and Verification
Verification is used by the corridor stakeholders to show that the as-built system and sub-systems meet all their requirements and match the design. Integration and testing and verification are closely linked processes in which one follows the other until the entire ICMS is ready for operational deployment. The system components are tested and verified as individual units. These components are then integrated and verified as sub-systems. This process may involve multiple levels of subsystems, with smaller sub-systems integrated into larger subsystems and verified, with the entire process continuing until all sub-systems are finally integrated (as a system) and verified.
A verification plan documents the procedures for testing and verifying the components, sub-systems, and system(s). The plan establishes a test case and verification technique for each requirement and for each design element (with each test mapped to a specific requirement via the traceability matrix). Each test case includes step-by-step procedures for conducting the test and the expected outcomes. Additionally, the verification plan provides general guidance for all verification activities, including identification of the verification participants and their respective roles and responsibilities, a schedule of the verification activities, and the identification of any required test equipment and simulation software. The preparation of verification plans should commence at the same time the requirements are developed as a means to show that the requirements, as written, can be verified. The test cases and verification procedures should be written at the end of the detailed design effort.
System Deployment, Verification and Acceptance
Following verification of the ICMS subsystems (including any enhancements to network systems within the corridor) the ICMS is integrated into its intended operational environment. ICMS verification is done in two parts:
- Under a controlled environment (i.e., factory acceptance test).
- Within the environment in which the ICMS will operate (i.e., site acceptance test).
System verification may take several weeks to complete (sometimes referred to as the system start-up or burn-in period) to ensure that the ICMS operates satisfactorily. Many system issues (e.g., memory leaks) may surface and become apparent only when the ICMS is operating in the real world environment for an extended period of time. These start-up issues can take time to address and the schedule should provide time for shaking out any problems encountered during system verification.
Once the system verification is completed, the ICMS is accepted by the corridor stakeholders and moves into the system validation and operations and maintenance stages.
System Validation
Validating the ICMS is a key activity of the corridor stakeholders, and constitutes the initial phase of evaluation. It is here that the system's performance is assessed against the needs, goals, objectives and expectations as documented in the Concept of Operations. The validation effort should commence as soon as possible following system acceptance in order to asses the strengths and weaknesses of the ICMS, and to identify new opportunities. As a result of the validation, new needs and requirements may be identified. It is emphasized that this activity does not check the work of the ICMS integrator or the system suppliers; that is the purpose of system verification.
The validation plan should be developed to indicate who will be involved in the ICMS validation and their responsibilities, the schedule, how and where the validation will take place (e.g., before and after study), what resources are needed, and the criteria against which the assessment of the ICMS will be based (i.e., needs, goals, and objectives).
Other Activities
During system integration, in preparation for ICMS verification and validation (and on-going operations and maintenance), several additional activities need to occur, including:
- Develop and input ICMS database (e.g., device locations and names, graphic displays, and Scenario / Response Plan information including locations, contacts, route and modal shifts, implementation rules, DMS messages, CCTV presets, traveler information, etc.).
- ICMS operation and maintenance documentation (e.g., system description, operation manual, system administration manual, equipment maintenance and service manuals, as-built drawings).
- Training the agency staff and other users (including development of the training plan and related materials).