Guide to Public Key Infrastructure (PKI)

Why is Public Key Infrastructure important?
Public Key Infrastructure is pivotal in ensuring secure data transmission in a network. It provides a framework for creating a secure method for exchanging information based on public key cryptography. It helps in internet banking, confidential email and other secure data transmissions.

What is Public Key Infrastructure?
Public Key Infrastructure (PKI) is a set of roles, policies, hardware, software and procedures needed to create, manage, distribute, use, store, revoke digital certificates and manage public-key encryption. The purpose of a PKI is to facilitate the secure electronic transfer of information for a range of network activities such as e-commerce, internet banking and confidential email.

How does Public Key Infrastructure work?
In PKI, digital certificates are exchanged over the network. These certificates contain the public keys. The sender encrypts the message using the recipient's public key. Upon receipt, the recipient uses their private key to decrypt the message. Since the private key is never shared, it provides a secure method of communication over a non-secure network, like the internet.

Exam Tips: Answering Questions on Public Key Infrastructure
Understanding the basic terminologies associated with PKI such as Certificate Authority (CA), Registration Authority (RA), digital certificates, public and private keys is crucial. Whenever a question involves secure communication over the network, think about PKI. Ensure you understand how keys are distributed and why the private key never leaves the original individual. Remember, the public key is used to encrypt and the private key is used to decrypt.