Estimation and removal or routing congestion

This presentation is intended to open up a discussion on the problem of predicting and optimizing congestion, early in the design process. Though one may be tempted to keep the horizons as broad as possible and speak about prediction and optimization of congestion at system-level specification, I believe at the present, a more realistic approach would be to focus on the congestion estimation and optimization during a combined logic/layont optimization approach, or perhaps in a pre-layont environment. Specific issues to be discussed may include: How do you define congestion or tangle in an unplaced netlist? How to measure it? What can be done to improve congestion? How to identify specific congestion problem areas?