The LDRA tool suite is the premier choice for building quality into defense systems software, from the simplest system to mission and safety critical software. Many current and next generation military systems have achieved their software quality objectives with the aid of the LDRA tool suite, including the avionics suite for the F-35 Lightning II (Joint Strike Fighter) project, for which the LDRA tool suite was the chosen software test tool.
Meeting both delivery schedules and feature completeness are of primary concern to defense procurement agencies. To this end, companies strive to develop mature software development practices via the adoption of maturity models such as the Capability Maturity Model Integrated (CMMI).
Developed by the Software Engineering Institute under contract with the U.S. Department of Defense, CMMI is used to appraise how well an organization's processes compare to CMMI best practices, resulting in the organization being granted an appraisal level from 1 to 5, from least to most mature. CMMI was created as a way for US defense procurement agencies to assess the ability of vendors to fulfill contracts on time, on budget and to specification. As a means of achieving maturity, vendors are increasingly looking to the development guidelines and metrics outlined in RTCA Inc. document DO-178B, Software Considerations in Airborne Systems and Equipment Certification as a reference. In addition, vendors providing safety critical systems to British Ministry of Defense must satisfy Defense Standard Def Stan 00-55.
Both DO-178B and Def Stan 00-55 are fundamentally process documents, defining the key elements required for the development of software, both safety critical and otherwise. The LDRA tool suite is the most complete software validation solution for supporting the entire defense software development process from requirements through to deployment, helping to eliminate or reduce labor intensive and error prone elements of the process:
1. Requirements Traceability - Both DO-178B and Def Stan 00-55 advocate a requirements driven process, whereby all components of deployed software are traceable to the original high level requirements, resulting in 100% Requirements Test Coverage and a requirements traceability matrix. TBreq is the only Requirements Traceability solution supporting the tracing of requirements throughout the entire development process. Using TBreq, requirements are traced from system level through to individual software components, including tracing the verification artifacts such as code standards compliance reports, test cases and structural coverage analysis data that were generated to validate test completion and completeness. TBreq then provides the Requirements-Based Test Coverage Analysis required and automatically generates a requirements traceability matrix.
2. Coding Standards Compliance - One of the major tenets of both DO-178B and Def Stan 00-55 is defining and complying with a Software Coding Standard. The LDRA Testbed® product static analysis capabilities can be used to enforce coding standards compliance, and can also be used to create a custom coding standard, for which the many built-in coding standards can be used as a reference.
3. Structural Coverage Analysis - Required by both DO-178B and Def Stan 00-55 to assess test effectiveness, helping to ensure that 100% of the software is tested. DO-178B requires specific coverage analysis criteria for the 3 most safety critical avionics safety levels. The most safety critical require Modified Condition/Decision Coverage (MC/DC), with the next two levels requiring Decision Coverage (DC) and Statement Coverage (SC), respectively. Def Stan 00-55 advocates the use of the Linear Code Sequence and Jump (LCSAJ) coverage analysis at the unit test level. The LDRA Testbed product saves endless hours of using a highlighter pen to identify tested and untested code by providing automated coverage analysis measurement to all of these types of coverage methods.
4. Object Code Coverage - In order to ensure that the system object code is an accurate translation of the high level language, both DO-178B and Def Stan 00-55 require some level of proof this translation, which object code coverage helps to provide, ensuring that 100% coverage at the object code level is achieved when 100% coverage at the source code level is achieved. The Testbed Object Box coverage module enable the automated measurement of the object code, helping to ensure that this DO-178B objective is met.
5. Control and Data Coupling - DO-178B requires that the data coupling and control coupling between software components be assessed in order to validate the strength of isolation between functionally independent software components. The LDRA Testbed product provides visibility of the data and control flow between components that enables this requirement to be addressed.
6. Tool Qualification - In order for the Structural Coverage Analysis results from a tool to be accepted as valid data for certification, DO-178B defines a process for qualifying a coverage analysis tool as a Software Verification Tool that verifies that the tool provides confidence at least equivalent to that of the process(es) eliminated. LDRA provides a Tool Qualification Package that includes documentation and test procedures required to ensure that Testbed can be qualified in a customer's environment.
7. Secure Code - An emerging requirement is the need for secure code in avionic systems that communicate with the ground. The Testbed coding standards capability provides the ability to assess code against both the CERT-C secure coding standard and the Common Weakness Enumeration database, ensuring that deployed defense code meets the highest secure standards.