 |
||
|
Advanced Search |
||
|
|||||
|
Reuse Analysis < Verification & Validation < Results Home
|
|
Click here to complete a short survey. The results of this survey will be used to help us improve the research program and this website.
Click here to view research projects that had new research results added in the last 90 days.
|
| Mitigating the Risk of Legacy Software on NASA Spacecraft | |
| Point of Contact |
Andres Orrego Andres.S.Orrego@ivv.nasa.gov |
| Dates | November 2004 - September 2007 |
| Problem | The purpose of this proposal is to identify and determine the impact of using legacy software on NASA spacecraft, and to develop tools that mitigate the risks of using legacy spacecraft software. Routinely, the reuse of spacecraft software is a part of NASA's IV&V program scenario. However, the legacy software is not currently verified or validated for its new environment, even though the legacy artifacts may be available to the IV&V team. Further, while the various IV&V teams often see the need to evaluate the reused code, they have no data to make an argument for re-verifying that code. The truth is that the reuse of NASA spacecraft flight software is not fully understood. GST will help NASA understand the ramifications of using legacy spacecraft software, and to help NASA mitigate the risks of using legacy spacecraft software by developing a "Legacy Software Toolset." The business case will document the current environment for legacy software used on NASA spacecraft (As-Is environment), and will document alternatives that mitigate risks of using legacy software for spacecraft missions (To-Be environment). We will prepare legacy software studies and impact reports as a part of the documentation of the As Is environment. GST will help NASA mitigate the risks of using legacy software on NASA spacecraft by developing a legacy evaluation toolset that will help NASA to analyze, verify, and validate the legacy software efficiently and inexpensively for its new environment. GST will perform this project in four phases that are each one year long. |
| Objective | There are a variety of NASA spacecraft programs that have used legacy software from a previous software effort. For example, SIRTIF uses Genesis code; Genesis uses Odyssey code; Odyssey uses MGS code; MGS may use Mars Observer software, etc. The following organizations have had flight software on more than one spacecraft: * Lockheed Martin * JPL * Spectrum Astro * Orbital * Goddard * Ball IV&V analysts understand that legacy spacecraft software is reused, and believe that the reused software should be verified or validated, but have no supporting business case to make an argument for performing IV&V on the legacy software. When IV&V teams identify software reuse as a risk, the typical response by the project team is that the software is "mature, stable, and did not experience problems in the past. Therefore, it does not need to be verified or validated." This rationale was used by the Ariane 5 and Titan/Milstar teams to justify why it was not necessary to evaluate the reused software. In both cases, the spacecraft was lost due to problems directly related to the reused legacy code. To help NASA understand the ramifications of using legacy software, as well as to mitigate the risks of reusing spacecraft software, GST proposes to: 1. Document the As-Is NASA legacy spacecraft software environment. 2. Identify the impact of legacy software on the development life-cycle elements. 3. Develop alternatives that mitigate the risks of using legacy software for spacecraft mission (To-Be environment), and formulate an IV&V plan to evaluate legacy software. 4. Develop a legacy evaluation toolset. |
| Results |
Facility Initiative Technical Presentation.ppt Software Reuse Study Report - (Sanitized).pdf SAS 06 Executive Presentation.ppt SAS 06 Technical Presentation.ppt Impact of Using Legacy Software on NASA Spacecraft Report - (Sanitized).doc IV&VWithReuseInMindV1.0Sanitized-Phase 3 Final Report (Sanitized).pdf SAS_07_TechPres_GST-MRLS_Orrego.ppt SAS_07_Exec_Brief_GST-MRLS_Orrego.ppt SRAE Training Slides.ppt SRAE Tool Prototype version 1-1.zip |
| Keywords | software reuse, software validation, legacy software, error checking |
| Categories |
Reuse Analysis |
|
| |
|
Curator: Josh Stonestreet NASA Official: Lisa Montgomery |
|
NASA Privacy, Security, Notices |