A cryptographic key is a special set of data used to encrypt and decrypt information sent over the network. Cryptographic keys are used to determine authenticity codes and to verify electronic digital signatures.
The success of decryption will depend on the key used, and if for any reason access to it is lost, it will be impossible to decrypt the data.
The length of the cryptographic key
The amount of information stored in cryptographic keys is measured in bits. Length is an important parameter of cryptographic strength in encryption algorithms that are used in the modern world. With a cryptographic key length of 128 bits or more, maximum reliability is ensured, because to decrypt such data, it is necessary to use super-powerful software and hardware complexes (supercomputers).
Penetration testing
Varieties of cryptographic keys
Keys in cryptography can be different depending on the specific algorithms that use these keys. There are 2 main types:
- Symmetrical (or secret). They are used within the framework of symmetric type algorithms (for creating authenticity codes, for encryption). The main function of this type of keys is reverse or direct cryptographic conversion (encryption/decryption, MAC verification). This approach ensures a fairly high confidentiality of information.
- Asymmetric keys. These types of keys are used in asymmetric encryption algorithms (for example, when verifying an electronic digital signature).
Asymmetric keys are key pairs consisting of two different keys:
- Private key. It is available only to its owner. In order to guarantee complete confidentiality and security of data and protect it from intruders, the private key must be kept secret by its owner from third parties.
- Open (Public key). A “public” key that can be published in the public domain to verify an electronic digital signature and to prevent the actions of intruders on the part of the document’s certifier if he refuses to sign it using an EDS. Such a cryptographic key is defined as a certain component of the private key.
A key pair (an asymmetric cryptographic key) has one important property — the secret key makes it easy to determine the public key, but if you use the public key to determine the private one, then an attacker will not succeed.