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What is cryptography?

In general, cryptography is the set of encryption techniques and linguistic alteration of certain messages to make them inaccessible to unauthorized recipients. It is a word that comes from the Greek “kryptós” (secret) and “graphé” (writing); it is, therefore, a secret writing.

In the field of computers, cryptography aims to protect the confidentiality of documents and data through systems of code to prevent security threats on the internet.

Cryptography is the set of techniques for encrypting information; cryptology is the discipline that studies its encoding, algorithms, and protection systems to ensure the security of personal data.

The cryptographic system is considered successful when a cyber-criminal with a special ability to breach a system fails to break these encryption codes.

What is cryptography for?

The main function of cryptography is to maintain the digital integrity and security of users, as well as to ensure the protection of their private information and the operations they perform and share on the network. This way, anyone who does not have keys or authorization to access the information will not be able to decrypt it.

Cryptography aims to ensure the privacy of information through the design, implementation, and use of code and encryption systems.

How is computer cryptography classified?

Cryptography can be divided into three types:

  1. Secret key (also called symmetric): uses a unique key both to encrypt and decrypt the information. This way, both the sender and the receiver must have the same key.
  2. Public or private key (also called asymmetric): it uses one key for encryption and another for decryption, one public and one private. The first, anyone can access, while only the owner has access to the second.
  3. Hash functions: they do not use keys but algorithmic systems and mathematical formulas to encrypt the information irreversibly, generating a fingerprint.

Regardless of the type, cryptographic encryption allows the information exchanged on the network, both that which is sent and that which is received, to be encrypted during navigation. An example of this is the use of digital certificates for sharing user data and information.

What are the main features of cryptography?

In general, cryptography should ensure:

  • Confidentiality: it is only accessible with authorization.
  • Association: an action is linked to an authorized person or management system.
  • Integrity: for the guarantee that the information is complete and correct.
  • Authentication: through mechanisms that allow verifying the person’s identity.
  • Privacy: for both personal communications and banking transactions through network channels.
  • Non-rejection or repudiation: after having transferred information, no interlocutor can deny their intention to do so.

What are the uses of cryptography?

The most common form of network cryptography is through private passwords to keep confidential material found on it secure. Cybersecurity techniques are used to develop combined encryption algorithms to encrypt and protect data that belongs to people and companies.

There are day-to-day activities that make it necessary to implement cryptographic algorithms to protect operations, devices, and equipment connected to the network since their use implies working with confidential information, such as: withdrawing cash at ATMs, online purchases, renewing streaming service contracts, or using e-mail or any mobile device connected to the network.

On the web, URLs that start with HTTPS have a public and a private key that are used together to encrypt the data. When a browser logs in with a web server, the latter sends it a public key. Then, there is an SSL handshake – a greeting between the browser and the server, establishing a secure connection. That way, the browser recognizes the link to be safe.

These protections for confidentiality, authenticity, and integrity, which are available through cryptographic protocols such as SSL, make it possible to protect user information from malicious uses. In addition, they provide assurance that users are communicating properly with timely and relevant systems.

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