Lightweight Public Key Infrastructures (PKI)
Formal
A public key infrastructure (PKI) supports the distribution and identification of public encryption keys, enabling users and computers to both securely exchange data over networks such as the Internet and verify the identity of the other party.
Practical
Without PKI, sensitive information can still be encrypted (ensuring confidentiality) and exchanged, but there would be no assurance of the identity (authentication) of the other party. Any form of sensitive data exchanged over the Internet is reliant on PKI for security. PKI provides a chain of trust, so that identities on a network can be verified. However, like any chain, a PKI is only as strong as its weakest link.
