The method of securing digital communications through authentication, encryption, and electronic signatures is a process known as Public Key Infrastructure (PKI). In a dynamic distributed (IoT) ecosystem, cloud storage and computing infrastructure, the cross-border digital identity platform, and so on, the traditional PKI systems are also vulnerable to the creation of trust monopolies, single points of failure, and limitations of scalability due to their dependence on a centralized Certificate Authority (CA). This work develops Blockchain-based PKI TrustRank-PKI, which leverages a trust-based consensus mechanism to address these shortcomings. In TrustRank, the validation aspect is not given by the classic consensus schemes, such as Proof of Work and Proof of Stake, but by dynamic values of trust based on the behavioral diagnoses of a node, its recommendations, and reliability. The ability of this design to curb Sybil attacks and collusion has been a remarkable element since it would serve to limit the number of trustworthy stakeholders and therefore reduce the extent to which the certificate would be influenced, as well as administered by a few. Globus has presented verifiable trust graphs to support audits and proofs of trust relationships and Zero-Knowledge Proofs (ZKPs) to support privacy-preserving authentication of identities. Taken together, all these innovations allow the safe, scalable, and modifiable deployment of certifications and, at the same time, increase transparency, decentralization, and accountability.