Towards a Universal Digital Identity- A Blockchain-Based Framework for Borderless Verification

Identity is the cornerstone of trust in modern society, yet current systems remain fragmented, document-based, and restricted by national boundaries. Physical passports, national identity cards, and paper records continue to define global mobility and access to services, despite being vulnerable to fraud, inefficiency, and exclusion. This paper argues for the establishment of a universal digital identity (UDI) hosted on a decentralised blockchain network. Under this model, each individual undergoes a one-time biometric enrolment capturing face, fingerprint, and voice data secured through cryptographic hashing and immutably stored on a blockchain ledger. A unique digital identity number (UDIN) is then generated, enabling retrieval of identity records worldwide by authorised institutions. Verification may occur in two ways: by presenting the UDIN or by frictionless biometric authentication, such as smiling at a camera or placing a finger on a scanner, instantly confirming identity against the blockchain. This system eliminates the need for physical documents, reduces fraud, lowers compliance costs, and enhances global mobility and inclusion. The paper sets out the vision, necessity, operational framework, and implications of a blockchain-based UDI, arguing that such a transformation is both inevitable and essential for the future of the digital economy.