Cryptography is the most reliable way to ensure information security. Its essence lies in the transformation of data using encoding. In the article we will talk in detail about cryptography, its principles and types.
Principle and application
The message is encrypted thanks to a special algorithm (key) and only after that it is sent to the recipient. In order for the recipient to read the message, it is decrypted with the same key. This method allows you to restrict access to information to third parties.
There are many methods for encrypting messages and audio files. However, not all of them are equally reliable.
Each encryption method is evaluated in terms of the following factors:
- Crypto resistance. It determines how strong the cipher is. That is, how difficult it is to decrypt it by selecting keys. The most reliable methods are those where it is necessary to enumerate all possible keys to decrypt the message.
- The volume of the encrypted message. In order for the message transmission speed not to suffer, the size of the encrypted message should not greatly exceed the size of the original one.
- No errors. Some techniques fail, due to which the content of encrypted messages is partially or completely lost. Therefore, before implementation, the selected encryption method is checked for errors.
- Speed of encryption and decryption. The faster the message is encrypted, transmitted and decrypted, the preferred method. Modern methods allow you to convert information in a few seconds.
- Affordable cost. To evaluate this indicator, the cost of the algorithm is compared to the financial consequences in the event of a data breach.
All these parameters are important when choosing, but the key is the cryptographic strength of the cipher.
Encryption methods
There are two types of data encryption: symmetric and asymmetric. The symmetric method involves using the same key to encrypt and decrypt data.
Symmetric encryption is widely used to ensure the confidentiality of information. Popular algorithms DES, 3DES, AES, IDEA refer to the block encryption method. This means that the information is encrypted in blocks, the number of which is determined by the amount of data in the message.
The advantage of the technique is that it can be easily integrated into the program code of the information exchange system, thereby providing automatic encryption. It can also be used to secure messages, develop authentication systems, and identify users.
But there are also disadvantages. So symmetric methods require periodic replacement of keys and the development of a security system for the keys themselves. If intruders can gain access to the keys, the protection system will lose effectiveness.
Asymmetric encryption uses different keys for encryption and decryption. This method is also called public key encryption because the sender of the message transmits the public key to the recipient over an insecure communication channel in order to decrypt it.
The principles of asymmetric algorithms are incorporated into the system for creating electronic digital signatures. The secret key is unique and protected from tampering, so documents sent on behalf of the signature owner, but encrypted in a different way, with unauthorized decryption by the public key, will lose their semantic load.
Asymmetric encryption technology is used mainly in network protocols to protect open channels of information transmission. For example, in network correspondence.
The procedure for encrypting and decrypting messages is simple. The recipient and sender use two types of keys: private and public. The information is encrypted with the private key, and the public key decrypts it. This security system is much more effective than symmetric encryption.
To implement an asymmetric encryption system or obtain a unique electronic digital signature, the user must use a special program that generates keys. There are several cryptosystems that have this capability. The most famous universal cryptosystem RSA, which not only generates keys, but also allows you to transform information.
The only disadvantage of an asymmetric encryption system is the need to protect the private key. However, the generation and EDS algorithms are designed in such a way that the use of this key requires the participation of its owner.
What about at the legislative level?
Data encryption is regulated by the FZ-149 law, which gives an idea of the participants in the process and the actions themselves. The law FZ-152 deals with personal data that are considered the object of actions.
The laws say that access control, registration and accounting, information integrity, encryption, virus protection, intrusion detection must be implemented to protect data.
To comply with the requirements, the organization must have a license to perform work and provide services when working with information related to state secrets. The staff should include qualified employees with the necessary education and work experience.
Without cryptographic data protection, any information activity is impossible today.