Security model for protecting intellectual property of state-of-the-art microfluidic biochips
Introduction
To date, a number of biological devices have been developed to easy and simplify from the biomedical and biochemical laboratory synthesis to information technology. One of such devices is biochip, also termed as lab-on-a-chip (LoC). In traditional laboratories, the steps of bioprotocol operation are done manually by using test tubes for different mixing/dilution operations and microscopic detectors for analyzing the experiments. To make this whole bioprotocol process automated, and to perform biomedical analyses of a very little amount of samples at low cost, biochips are invented. Biochips make the process faster as compared to traditional test tube-based laboratories. The research domain of biochip is an interdisciplinary field including biotechnology, chemical engineering, mechanical engineering, electronics, and computer science.
Microfluidic is the system of science and technology that manipulates individual small droplets of samples and reagents using channels and reduces their rate of consumption [1]. The domain of microfluidics area has four parents: molecular analysis, molecular biology, microelectronics, and biodefence [2]. Digital microfluidic (DMF) biochips, Micro-electrode-dot-array (MEDA) biochips, Paper-based (PB) biochips, Continuous-flow microfluidic (CMF) biochips, and Programmable microfluidic devices (PMD) are some promising microfluidic biochips for different bioprotocols.
Microfluidic biochips become very popular because these offer several useful capabilities as follows.
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Biochips are fast in doing their intended operations, i.e., dispense, transportation, mixing, splitting, etc. [3].
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Microfluidic biochips are suitable for designing automatic analyses of the repetitive steps of bioprotocols in laboratories by replacing complex equipment [4].
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Biochips can be used in biological computing, such as enzymatic analysis, DNA analysis, surface immunoassays, proteomic analysis, cell culture, and toxicity monitoring [5].
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These microfluidic biochips are low cost, reliable, quick analysis with much sensitivity and fast clinical diagnostic tool for many medical diagnoses (point-of-care diagnoses) with high resolution.
As biochip popularity is increasing day-by-day, its business opportunities have grown exponentially in the last two decades. The global biochip market is expected to gain $12.3 billion by 2025 from $5.7 billion in 2018 [6]. This is achieved by the sales, investment, and acquisitions reported by microfluidic companies [7]. Due to such heavy gain, the chance of attacking microfluidic biochips by unscrupulous people is increased day by day. These attackers try to alter its operation, destroy more costly samples, and pirate the microfluidic biochip. The motivations behind these attacks are revenge, illegal profits, politics, terrorism, and/or personal gain. Attacks on microfluidic biochips have emerged as a serious rising threat and call for an immediate solution. As a result, securing such biochips is of paramount importance. So it is urgent to conduct research on security issues for existing microfluidic biochips to achieve accurate results and maintain its reliability, trustworthy and confidentiality to its intellectual property (IP).
In this paper, we identify the security threats and vulnerabilities associated with the actuation sequences of different types of microfluidic biochips. We proposed a security model with ciphertext-stealing mechanism for such actuation sequences. The key contributions of this research paper are as follows.
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We explore different security issues along with their challenges in microfluidic biochips from various possible malicious purposes.
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We analyze a number of related work and discuss logic encryption, camouflaging with their limitations in this research article.
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We design a security methodology to evade these challenges and attacks on the storage device and communication of actuation sequences along with secret keys.
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We explore pseudo-random numbers for better aspects of both security and performance of the proposed scheme.
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The proposed scheme is applied to different real-world bioprotocols to assure its efficacy in terms of encryption time and extra memory usage required for its implementation in the biochip platform.
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We analyze the post-decryption regime that is vulnerable to IP theft/piracy and propose preventive solutions to make biochip designs trustworthy in each stage of the biochip design flow.
The remainder of this paper is organized as follows. Section 2 presents the basic concepts of bioprotocol and actuation sequences for proposed work along with the working principles of different microfluidic biochips. Section 3 assesses related work on security issues in microfluidic biochips with an elaboration regarding extended tweak block chaining (X-TBC), Diffie–Hellman key exchange scheme, logic encryption, and IC camouflaging. Section 4 presents the proposed scheme with its performance in Section 5. Comparisons and analyses of simulation results are done in Section 6. Finally, conclusions and future work are drawn in Section 7.
Section snippets
Actuation sequences for different types of microfluidic biochips
A bioprotocol is a procedure to determine the concentration, potency or purity of a fluid in biochemical analyses [8]. Its different operations are represented by a “sequencing graph” as shown in Fig. 1(a). This section presents a more detailed structure of the actuation sequences for different types of promising microfluidic biochips available in the market and/or under research going on.
CMF biochip is the prominent first generation category of microfluidic biochips that consists of fixed
Related work on security concerns
In this section, we focus different work related to security concerns.
Proposed scheme: Securing actuation sequences of microfluidic biochips
Security model with XORing and Galois Field (GF) multiplication in the domain of GF() is a new direction towards security concern for avoiding IP theft of actuation sequences for different types of microfluidic biochips.
In this paper, a novel scheme for Securing Actuation Sequence using XOR-Encrypt-XOR based Tweaked Code Book mode with ciphertext-stealing (SAST) for any short final actuation block is proposed.Tweaked Code Book (TCB) is the mode of operation where the actuation sequence is
Discussions on performance of SAST
We take the following existing known analysis factors into the consideration to analyze the performance of the proposed model with assuming a biochip user is an attacker.
Simulation results
In this section, we compare SAST scheme with exhaustive case using existing different bioprotocols [48]. The speed presented in Table 2 for bioprotocols is obtained from Python implementation and taking different sample actuation files as input with the help of UCR Digital Microfluidic Static Synthesis Simulator, UCR DMFBSSS [49], considering the active pins as “1” and remaining pins as “0” in each cycle of bioprotocol because of actual actuation sequence files, i.e., IP of bioprotocols are
Conclusions and future work
In SAST paper, we are the first to present a reliable, authentic, and efficient security model for securing actuation sequence of microfluidic biochip in each stage of its design flow along with keeping secret keys of both AES and FMUX/dummy mix-split techniques confidential. The proposed scheme produces a remarkable throughput along with enhancing security aspects in online sharing and remote-access of actuation sequence. Diffusion and confusion methods also frustrate attackers from making any
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgments
We gratefully acknowledge the financial support from the QIP, IIT Roorkee (India) for the preparation of this material. This work of D. Gountia was supported partially by the financial support from the Continuing Education Centre (CEC) in IIT Roorkee, India. This work of S. Roy was supported partially by the early career research award (grant #: ECR/2016/001921) sponsored by SERB , Govt. of India.
All authors approved the version of the manuscript to be published.
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