What is a cryptographic key?
A cryptographic key is a sequence of bits that is used by a cryptographic algorithm to convert plain text into encrypted text or vice versa. This key remains private and ensures secure communication.
A cryptographic key is the core of cryptographic operations. Many cryptographic systems include pairs of operations such as encryption and decryption. A key is a piece of variable data that is provided as input to a cryptographic algorithm to perform this type of operation. In a properly designed encryption scheme, the security of the scheme depends on the security of the keys used.
Cryptographic keys are symmetric or asymmetric. Symmetric encryption only requires one key that is used to encrypt and decrypt data. Asymmetric encryption uses two different keys: one for encryption and one for decryption. One Certification Authority (CA) provides public / private key pairs using the public key infrastructure. The registration process for digital certificates begins before the status of the user's digital certificate is communicated to the certification authority.
Cryptographic keys can be further indexed by the purposes for which they are used, which can include data encryption and decryption, digital signature verification, digital signature creation, message authentication, key transport, and key wrapping.
The length of a key is usually expressed in bits. A longer key makes it more difficult to crack the encrypted data; However, a longer key results in longer periods of time for encryption and decryption processes to be carried out.
The CA provides the keys. The private key is given to the key requester. The public key is published in an open access directory. Private keys never travel over the internet and therefore remain private.