Intellectual property metering(8)

Abstract. We have developed the first hardware and software (intellectual property) metering scheme that enables reliable low overhead proofs for the number of manufactured parts and copied programs. The key idea is to make each design slightly different d

becomes obvious. One naive approach is to use a serial number, however, it is visible and almost trivial to be removed. In this paper, we propose a scheme that embeds a unique identification number inside of the product.

3.2 Requirements and Objectives

Before the discussion of technical details, we first analyze the requirements and objectives. Four basic questions have to be answered:

P1 How to create many distinct copies with the same functionality?

P2 Once two identical copies are found, how can we prove our ownership, i.e., how can we convince others that we are not the pirates?

P3 How many tests we need to conduct before we gain a certain level of confidence that there are no unauthorized on the market?

P4 If there are unauthorized copies, how can we estimate the number of copies that they have made?

The existing watermarking techniques provide solutions to problem P2: During the design synthesis, we embed our digital watermarks and later on retrieve such watermarks for authorship [19]. The last two questions are interesting for obvious reasons. P3 esti-mates designer’s effort to prove foundry’s honesty, while P4 provides valuable on-court information for the designer. We will build statistical models and address them in the next section. To end this section, we discuss the requirements for solutions to the first question:•Correct functionality: Although we want the system to be distinct, they must have exactly the same functionality.

•Large number of different copies: The method has to be capable of producing huge amount of distinct copies (from tens of thousands to millions) to accommodate to the market.

•Low overhead: The degradation of system’s performance due to the large number of different copies has to be kept at the minimal level, if zero-overhead is not achievable.•Transparent to design and test: The creation of different copies has to be transparent to the manufacturing and testing. Otherwise, it will make the mass production impos-sible. For this reason, we suggest post-processing, i.e. keep most components of the chip the same and make small changes at the final stage of the fabrication.•Resilient against attacks: Attempts to making distinct extra copies or duplicated cop-ies without being caught will be difficult, costly, and time-consuming.

4 Hardware and Software Metering Techniques

In this section, we propose and analyze a number of ways for hardware and software metering. There are several alternatives for implementing the identification logic within the control path logic for hardware protection. Our focus is control logic, because in mod-ern design it is usually a very small percentage of design area, often less than 1%. Each of the proposed techniques which have certain advantages/disadvantages.

4.1 Sequential Memory-Based Approach

In this approach the required data is stored in a family of PROMs (preferably non-recon-figurable e.g. OTP EPROMs). This data is then read out of the registers sequentially to form a control path. The fast improving memory technology is rapidly reducing on-board programming time and the required extra manufacturing processing steps. The advantages of this approach includes on-board programmability and small area overhead. However,