What Is Encryption?

Encryption uses a special algorithm to change the original information data, so that even if an unauthorized user obtains the encrypted information, he still cannot understand the content of the information because he does not know the decryption method. In aeronautics, it refers to the operation of adding a few control points on an image pair or an entire aerial photographic band by measuring and calculating the number of control points on the aerial photographic image.

The reason why encryption is secure is not because you do nt know the encryption and decryption algorithm.

Encryption related software

Encryption or software code obfuscation is also used in software copyright protection to counter reverse engineering, unauthorized program analysis, cracking and software piracy and digital rights management (DRM) of digital content.

This kind of encryption service is especially obvious in Android applications. Due to the increase in packaging parties, many special Android applications are decompiled, reverse analyzed, and repackaged. Therefore, many Android developers have to encrypt Android applications. Everyone focused on the development and operation of the App, and did nt have much time and energy to develop an effective App encryption method by themselves, so they spawned a third-party Android application encryption service provider, iCrypt, according to 36 . Ai Crypto is a third-party App encryption platform based on the SaaS delivery model. It allows developers to complete advanced app hardening online in just 5-10 minutes. Adding a protective shell to the App can effectively prevent the App from operating Avoiding the risk of being implanted with malicious code, secondary packaging, and copycat piracy, can also help developers save development time and costs.

Encryption category

Encryption algorithms can be divided into two categories: symmetric encryption and asymmetric encryption

Encryption

The following techniques can strengthen the security of encryption:

1. Don't use old encryption algorithms

Enterprises should stop using old encryption algorithms such as DES, and do not use their relative 3DES (triple data encryption standard).

2. Use the longest encryption key supported by the enterprise

It is recommended that enterprises use the maximum length of keys as much as possible, which can make it difficult for enterprises that cannot access the backdoor to crack the encryption of the enterprise. Today, AES 128 is robust, but if possible, use AES 512 or longer keys.

3. Multi-layer encryption

It is recommended that enterprises use multi-layer encryption whenever possible, which can increase the difficulty for attackers. If possible, you might want to encrypt every field, every table, and the entire database.

4. Securely store encryption keys

Perhaps the biggest problem facing enterprises is not that the encryption algorithm is left behind by the US National Security Agency, but that the password itself is only part of the encryption scheme. For other elements of the infrastructure, such as key management systems, companies must also keep them secure. Attackers are willing to deal with the weakest link in the security system. If an attacker can easily steal the key, why bother to crack the encryption algorithm?

Some companies give third parties keys to protect their data, especially if the company stores the data in a public cloud and is encrypted and protected by the cloud provider. The problem here is that the enterprise has no control over the keys, but must trust that the cloud provider's employees will keep the keys securely.

It would be far more secure if an enterprise could implement an encryption system that could keep keys in the cloud. Cloud encryption gateways that automatically handle encryption can help companies achieve this security.

5. Make sure encryption is implemented correctly

In fact, implementing a cryptographic system is not easy, because it has many dynamic parts, and any one part can become a weak link. You have to do a lot of research to ensure that encryption is implemented correctly.

What aspects of the encryption process are error-prone? In addition to keys being vulnerable, there are also implementations of CBC (Cipher Block Chaining). With CBC, you can XOR the plain text with a random block of text (also called the initialization vector) of the same length, and then encrypt it to produce a block of encrypted text. Then, the previous ciphertext block is used as an initialization vector to XOR the next plain text block.

The correct implementation of CBC requires a new initialization vector at the beginning of each process. A common mistake is to implement CBC with a static initialization vector that does not change. If CBC is implemented correctly, if we encrypt text blocks on two different occasions, the ciphertext blocks produced will not be the same.

6. Don't ignore external factors

External factors beyond the company's control have the potential to undermine the security of cryptographic systems. For example, SSL relies on digital certificates, and these factors depend on the integrity of the root certificate authority embedded in the browser (such as IE, Firefox, Chrome, etc.). But how do we know if it is credible, or if these certificate authorities are not under the guise of a foreign intelligence agency? Do you think this sounds far-fetched, but it may be true.

In addition, DNS is also a weakness that has to be taken seriously. As long as DNS is compromised, attackers can use phishing techniques to bypass encryption.

Of course, the possibilities of the encryption problem are highlighted here. A properly implemented encryption system can only be defeated in one case, that is, to test the key. It is not impossible to guess the key in a short time, but the possibility is very small. ^[4]