signalstorm和默认的time analysis有什么区别？

求大神指点下

求指点

这种东西UG上都有...
You can perform delay calculation at various stages of the design flow to continuously validate your timing. The Encounter® Digital Implementation System (EDI System) provides three delay calculator engines that you can use:
EDI System delay calculator engine
Used to provide quick delay calculation for design prototyping, optimization, and general timing analysis.
SignalStorm® delay calculator
Used to perform final delay calculation and timing analysis. SignalStorm provides better accuracy, can calculate multi-driver nets, and uses more advanced effective current source model (ESCM) modeling.
AAE delay calculator
Used to perform delay calculation, timing analysis, and signal integrity (SI) analysis.