Public Key Infrastructure is the comprehensive system required to provide public-key encryption and digital signature services.

Historically, encryption systems used symmetric cryptographic technology to secure data. Both encryption and decryption were performed by using the same digital key. Recently, cryptographic technology has been enhanced with the invention of public key cryptography which removes the need to use the same key for encryption and decryption. Keys come in a matched pair of "public" and "private" keys. Data is encrypted using the public key and can only decrypted using the private key.

Public Key Infrastructure technology uses both encryption and digital signatures to provide:

• Confidentiality - Data cannot be read without the corresponding key
• Authentication - Users can securely identify themselves to other users and servers on a network without sending secret information (i.e passwords) over the network
• Data Integrity - the verifier of a digital signature can determine whether or not digitally signed data has been altered since it was signed
• Non-repudiation - the user who signed data cannot deny signing the data

Amendments to Ontario's Land Registration Reform Act have removed the requirement for handwritten signatures and permit electronic signatures. Clients equipped with a security credential, which includes an encrypted digital signature, - Personal Security Licence - that uniquely identifies them, will be able to legally sign and submit title documents for registration.

Securing Your Information contains more details on how the personal information you provide in the Personal Security License Application is used and protected.

An electronic audit trail identifying transaction activity and leading back to the security credential further protects the system.