Security level of encryption algorithms

Reprinted:

Today, I saw a table on the Internet about the security and cracking complexity of the encryption algorithm. It is excerpted for future reference. The original table is in English and can be translated into Chinese for reference. In addition, I also found some information about cryptography. The appendix is later.

Security level of encryption algorithm (Cryptographic algorithms)

Security level (Security Level)			Working Factors (Work factor)	Algorithm (Algorithms)
Weak)			O (240)	Des, MD5
Legacy)			O (264)	RC4, SHA-1
Baseline)			O (280)	3DES
Standard)			O (2128)	AES-128, SHA-256
High)			O (2192)	AES-192, SHA-384
Ultra)			O (2256)	AES-256, SHA-512

Note: The "work factor" in the above table can be understood as the complexity of the cracked algorithm.

Cryptography-related information:

Cryptography, hash, and Hash Functions
Hash Algorithm: md4, MD5, Sha
Symmetric encryption: Des, idea, RC2, RC4, skipjack, RC5, AES
Asymmetric encryption: RSA, ECC

Proven algorithms (Insecure algorithms): md4, MD5, SHA-0, SHA-1, des

In theory, most algorithms can be cracked, but it takes a long time for many computers to perform parallel operations. The longer the key, the more resources are required. This increases the cost of cracking. As a result, no attacks or bypass attacks are initiated because of the high cost. At the same time, the longer the key, the higher the encryption and decryption cost, so you can choose an appropriate algorithm based on the value and confidentiality requirements of the information.

The hash algorithm is an irreversible algorithm, but collision may occur, which is fast. symmetric encryption uses a key for encryption and decryption. asymmetric encryption uses a public key and a private key for encryption and decryption, the speed is slower but safer than symmetric encryption. Generally, MD5 orShaAnd symmetric encryption can use 3DES orAES, Asymmetric encryption is optionalRSAOr ECC.

In addition, the hash algorithm here is slightly different from the hash algorithm used in the hash table. The hash algorithm used in the hash table does not require high security, but requires high performance and high discretization, therefore, MD5 or Sha algorithms are generally not used, but faster hashing algorithms are used.

What are common encryption algorithms?

Des (Data Encryption Standard): symmetric algorithm, Data Encryption Standard, fast, suitable for encrypting a large amount of data;

3DES (Triple DES): It is a symmetric algorithm based on Des. it encrypts a piece of data three times with three different keys, with higher strength;

RC2 and RC4: symmetric algorithms that use variable-length keys to encrypt a large amount of data, faster than DES;

Idea (International Data Encryption Algorithm) International Data Encryption Algorithm, uses a 128-bit key to provide very strong security;

AES (Advanced Encryption Standard): Advanced Encryption Standard, symmetric algorithm, is the next generation of encryption algorithm standard, fast, high security level, now an implementation of the AES standard is Rijndael algorithm;

RSA: A Public Key algorithm that supports variable-length keys. The length of the file block to be encrypted is also variable. asymmetric algorithms;

DSA (Digital Signature Algorithm): digital signature algorithm, which is a standard DSS (Digital Signature Standard). It is not an encryption algorithm strictly;

Blowfish uses a variable-length key, which can contain up to 448 bits and runs fast;

MD5: it is not an encryption algorithm, but a digest algorithm. MD5 processes input information in 512-bit groups, and each group is divided into 16 32-bit groups. After a series of processing, the algorithm output consists of four 32-bit groups. After these four 32-bit groups are cascaded, a 128-bit hash value is generated.

PKCS: the public-key cryptography standards (PKCS) is a set of public key cryptography standards developed by RSA Data Security companies and their partners, it includes a series of related protocols, such as certificate application, certificate update, certificate invalidation table publication, extended certificate content, digital signature, and digital envelope format.

Ssf33, ssf28, scb2 (SM1, others can be used;

Other algorithms: ElGamal, Diffie-Hellman, and ECC.