An overview of global routing

Global routing in VLSI (very large scale integration) design is one of the most challenging discrete optimization problems in computational theory. In this review paper of ours, we have presented a polynomial time algorithm for the global routing problem based on integer programming formulation with a theoretical approximation bound. The algorithm ensures that all routing demands are satisfied concurrently, and the overall cost is approximately minimized. Both serial and parallel implementation has been provided to develop several heuristics used to improve the quality of the solution and reduce running time. We provide computational results on two sets of well-known benchmarks and show that, with a certain set of heuristics, our new algorithms perform extremely well compared with other integer-programming models.