In the blockchain, the transaction hashes are implemented through public-key cryptography and hash functions. Hence, there is a possibility for the two users to choose the same private key knowingly or unknowingly. Even the intruders can follow the particular user's bitcoin transaction, and they can masquerade as that user by generating the private and public key pairs of him. If it happens, the user may lose his transaction. Generally, bitcoin technology uses random numbers from 1 to 2256. It is a wide range, but for a greater number of users, there should be one another solution. There is a possibility of digital prototyping which leads to the loss of more accounts. This chapter provides the device-specific fingerprint technology known as physical unclonable function (PUF) to be employed for authentication in a blockchain-based bitcoin environment. The random unique response from PUF ensures correct transaction. In this chapter, a new tetrahedral oscillator PUF has been introduced intrinsically. All the blockchain operations are carried out and verified with PUF response.
TopIntroduction
Bitcoin technology appeared 11 years ago; the decentralized ledger used in Bitcoin is implemented through blockchain technology. The blockchain technique has been proposed in October 2008 by Satoshi Nakamoto (Nakamoto, 2008). Bitcoin technique requires, some cryptographical techniques to control the transactions of Bitcoin among the persons who are involved in it, some hardware instruments to run the software, and the miners who are involved in maintaining the transaction ledgers.
Security issues have become the most challenging problem in Bitcoin, in the sender’s point of view. Bitcoin software issues some software challenges to the miners which should be solved within a particular time interval. This challenge makes the miners to find the Nonces for the specified block. The race to solve the challenge starts after the software releases the challenge. After a particular time, this will be closed. Within a stipulated time, who correctly solve the challenge will be rewarded. Other miners validate the answer. The transaction will be added to the blockchain. Most of the threats and blockchain concepts were discussed by Saraju et.al in reference (Mohanty et al., n.d.).
The design of security protocols is complicated due to the problem of creating software challenges and nonces creation. The security of Bitcoin lies in the software challenge; this must be resistant to power analysis attack physical and any side-channel attack. In addition to that, they must be unimaginable by anyone. Moreover, they must be computationally secured and reasonable to produce. The power and memory resources of the bitcoin chain should be less. In this chapter, PUF based blockchain architecture for bitcoin security is presented. Moreover, the enrolment and authentication protocols for the PUF assisted hardware in a blockchain network.
Many types of PUFs have been proposed. It can be categorized mainly into two types: Extrinsic PUFs and Intrinsic PUFs. Both are having its advantages and disadvantages. Based on coating materials, metal components, and memristors, extrinsic PUFs are manufactured. Based on delay properties, in simple logic gates, Intrinsic PUFs are generated. One new category of PUF is introduced in this article to produce the identity of that person. A tetrahedral oscillator (Muthukumar et al., 2019) PUF is proposed in this paper which is used as intrinsic PUF that can be used for the implementation of PUF based blockchain. In some places, PUF is used in place of Hashing operations which avoid more software computation of cryptographic hashes. Elliptic Curve generating module is additionally added with PUF structure to generate public keys. In the case of Proof of PUF-enabled authentication (PoP), the PUF module is responsible for generating the device’s unique identification.
Since the response of the PUF element is only known by the device manufacturer and the PUF holder, the behaviors are known only by them. Hence the probability of response duplication and counterfeiting becomes very less. The way that how the intruder is cheating the verifying device lies in the uniqueness and reliability of the underlying device. But in the presence of a PUF device, they can't meet the required conditions expected by the transaction proof chain.