Public Key Infrastructure (PKI) is a system of cryptographic technologies, policies, and procedures used to secure digital communications and verify identity online. At its core, PKI relies on a pair of cryptographic keys—a public key and a private key—where the public key is shared openly, while the private key remains confidential. These keys enable secure encryption, authentication, and digital signatures, ensuring that data remains confidential and integrity is maintained. PKI operates through a hierarchical trust model, where Certificate Authorities (CAs) issue digital certificates that confirm the authenticity of users, websites, and devices. This framework is essential for safeguarding sensitive transactions, such as online banking, email encryption, and secure website access (HTTPS). By establishing trust and enabling encrypted communication, PKI plays a critical role in modern cybersecurity.
Maintaining the confidentiality of the private key is fundamental to PKI security, as any unauthorized access to it can compromise the integrity of encrypted communications and digital signatures. If an attacker gains control of a private key, they can impersonate legitimate entities, decrypt sensitive information, and create fraudulent signatures, leading to identity theft, financial loss, and data breaches. To mitigate these risks, organizations must implement robust security measures such as hardware security modules (HSMs), strong access controls, and periodic key rotation. Additionally, adhering to best practices—such as avoiding the storage of private keys in unsecured locations and ensuring proper key lifecycle management—helps preserve the trust and security that PKI provides.