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As cryptography is becoming ubiquitous in our digital systems, cryptographic implementations are being deployed in unprotected devices that might get compromised by malicious parties. However, cryptographic primitives are designed to provide security in the black-box model, where attackers can only tamper with the inputs and outputs of the primitive, but they do not offer protection against white-box attackers, who can gain full control over the device running the cryptographic computations. Due to the high demand for software implementations of cryptographic primitives secure in the white-box model, many of these white-box implementations have been proposed in the last 20 years. Building secure white-box implementations is very challenging, even for basic cryptographic constructions such as block ciphers, and all published white-box implementations have been broken. In the first research objective of this thesis, we address the ambitious goal of designing secure white-box implementations of block ciphers. While the cryptanalysis of white-box implementations has significantly advanced in the last decade and many attacks have been published, little progress has been made in the design of white-box implementations and nearly all implementations have followed the same design method. In the thesis we describe the published white-box implementations of block ciphers, next we report our analysis of a common structural property exploited in most of the white-box attacks, the self-equivalence structure of the underlying block cipher. We conclude the first objective by summarizing the implicit framework, our novel white-box method that …