Research On Intellectual Property Protection Of Network-on-chip

With the development of integrated circuits into the SoC era, the design methodology of reusing IP(Intellectual Property) cores is widely adopted. Designers can obtain more and more IP cores, and integrate them to fulfill different functions according in a system. At the same time, how to solve the problem of communication of IP cores on one chip and how to protect the intellectual property of IP cores draw more attentions.To solve the problem of communication, people proposed on-chip network(Network-on-Chip), referred to as NoC. NoC brings a new on-chip communication method with significantly higher performance than the traditional bus architectures. Because of its high bandwidth and high scalability, more and more SoC designers adopt NoCs. To protect the IP cores, various protection methods have been proposed such as watermarking and encryption technology. However, there is not yet an IP protection technology proposed specifically for NoC. After investigating the characteristics of NoC and existing watermark methods, we propose two IP protection methods for NoC. The first method designs a special routing algorithm to protect IP of NoC. This method embeds a signature which contains the authorship of the original designer and the ID information of legal user into the NoC. By routing an authentication packet on the NoC, the signature can be recovered. The second method designs a node activating mechanism to actively lock the NoC. The method sets part of the nodes on NoC as nodes waiting to be activated(WN). When the NoC is powered on, the WNs must be activated by a key so as to work normally. After all the WNs are activated, the NoC can work with the full performance.The first method can be used to verify original designer and legitimate user of the NoC IP core. It is useful to solve the problems such as illegal usage, copying and distribution. By authentication we can determine the circuit is imitation of which design or redistributed by which user. Before infringements happen, the first method has no effects. The second method can provide active protection. An illegally gained NoC cannot work normally without an authorized key. Two methods are usually combined, in order to realize hierarchical protection.In this paper, we use the NoC simulator Noxim to validate the two methods. The experiment results demonstrate the effectiveness and low overheads of the methods.