In our world today, technology has tremendously advanced as compared to its former years during its inception. This has driven communication to a whole new level leading to the phrase, "the world has become a global village". This means that interactions and business transactions on an international platform can now traverse the idea of geographical location, with spreading knowledge being accomplished at the touch of the button. With an automated process, there comes a risk of all this information falling into the wrong hands. If the information being transferred through such communication channels goes unchecked, with regards to security, the implications are inherent to both users thus the need for basic encryption techniques i.e. Public Key Encryption abbreviated as PKC
PKCs are encryption techniques that use paired private of public algorithms to secure data through communication channels. There are two types of PKC algorithms: RSA and DSA. There are standards that have been established, Public Key Cryptography Standards, to guide on the deployment of public key cryptography If messages are to be sent via any communication channel, the sender encrypts the data using the recipient's public key whereupon receiving the data, the recipient will use their own private key to decrypt the data.
This means that public keys are "open" to the public for data encryptions and only the private key can be used to decrypt such data. Let’s assume user A and B are sending information, (e.g. 5566) over a secured/unsecured channel. If user B's public key algorithm adds 10 to the second and fourth numbers without interfering with the adjacent numbers, user B will receive the information as "515616". Upon receiving the number from user A, User B will apply his private key algorithm to decrypt the key. Keep in mind the private key has the algorithm need to decrypt the data i.e. Subtracting 10 from the specific sates to get 5566.
For data transfer over secured channels, this logic will fully achieve the intended objectives but for an unsecured channel, the risk exposure is high with regards to the security of the data. This is because continued use of one algorithm in data encryption establishes a pattern that allows easy decryption of said data, leading to an information leak. That is why there is a need for rotating public keys.
Rotating public keys means that the algorithm in use during data encryption is changed periodically to ensure that no malicious users develop counter private keys to the original public key. This reduces the need for constant monitoring to establish breaches in communication channels; it is a daunting task to monitor the channel yet the third party have their own unique key that if used, will not raise any alerts or alarms. Much of rotating public keys has become an easy task with the advancement of technology compared to the manual procedures that were in use.
In the case of TLS certificates, users can generate a Certificate Revocation List that allows serves to run client certificates against the list and prevent any unauthorized use or access to information. The frequency to which the keys should be rotated solely depends on what the users need and type of industry. It is good practice to have secured private and public keys to enhance data/information security or else risk exposing confidential communication to malicious hackers and crackers who live for the thrill of accessing channels not privy to them.