Site problems Architecture Analysis Architecture tools are essential to define the architectures for analyses. For time-critical elements of an architecture, time-line analysis is performed by using tools contained in scheduling applications. Architecture trade tools might also be specifically developed for a particular system to perform rigorous comparative performance, cost, schedule, and risk analyses between alternative architectures. Architecture alternative tool analyses compare system architectures to determine the best value solution(s). Viable architectures are defined technically/parametrically and operationally and prescribed for each architecture. In addition, outputs of associated tools such as Cost As Independent Variable (CAIV) sensitivity analyses, reliability models, risk analyses and others are also candidate inputs for comparative analyses. These tools are often unwieldy but necessary to support the architecture down selection of complex systems where there are thousands of parameters and numerous architectures to assess and compare. A few tools are available on the market to assess alternative architectures. One example is the Architecture Tradeoff Analysis Method (ATAM) developed by Software Engineering Institute (SEI). This method is an architecture evaluation technique.