Skip to main content

Currently Skimming:

1 Introduction
Pages 6-11

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.

From page 6...
... "Unlike hardware, software never dies."1 Software can be recorded and stored as a backup, and this backup can be used at any time in the future absent storage failures to reinstantiate as many exact copies of the software on as many copies of the target hardware as may be desired. Rather than return a system to its original state, much of software sustainment is involved with the design, development, and delivery of new functionality that offers incremental improvements over previous versions and recoding to fix issues or problems in the original software such as discovered defects and vulnerabilities.
From page 7...
... To collect more direct knowledge of the SWEG operational teams, committee members attended meetings and tours at two of the SWEGs: Hill Air Force Base 2  See NIST Computer Security Resource Center, Glossary: "Commercial-Off-the-Shelf," https://, accessed June 2, 2020.
From page 8...
... The limited number of avionics systems on an aircraft used dedicated wiring for operation. The 1960s avionics architecture sustainment concept logically matched that of other aircraft components, such as the hydraulics, landing gear, and control surfaces.
From page 9...
... The introduction of the MIL-STD-1553 data bus in the 1990s facilitated the change to a federated digital architecture: "The federated digital architecture allows for a more interrelated functionality between systems that were previously independent in architectures of the past."3 The federated architecture brought with it a marked increase in the avionics software content and exponential growth for the future (Figure 1.2) .4,5 Each component in the federated architecture had its own independent operating system and software.
From page 10...
... However, while the avionics architecture shifted to a heavy reliance on software, the organic organization structure lagged and continued to approach sustainment, as if the software components were predominately hardware. Throughout the evolution of avionics system and embedded software archi tectures, the challenge of government data access to source code and development 6  See TTTech, "Avionics Full-Duplex Switched Ethernet (AFDX)
From page 11...
... Second is that the inability to gain ­access to data rights and software development tools has slowed organic growth while perpetuating USAF reliance on contractor sustainment support.

This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More information on Chapter Skim is available.