A watermarking system for IP protection by a post layout incremental router

In this paper, we introduce a new watermarking system for IP protection on post-layout design phase. Firstly the copyright is encrypted by DES (data encryption standard) and then embedded by using an incremental router into the layout design. This watermarking technique uniquely identifies the circuit origin, yet is difficult to be detected or fabricated. The incremental router consists of a rip-up and a special re-router that inserts redundant bends into wires probabilistic. We evaluated the technique on various generated benchmark circuits to validate the completeness of the procedure. The results show it achieves almost 100% success for embedding with no extra area cost on design performances.