Comparison of various cryptographic algorithms

Algorithm selection: symmetric encryption AES, Asymmetric encryption: ECC, message digest: MD5, digital signature: DSA

Symmetric encryption algorithm (with the same decryption key)

Name	Key length	Operation Speed	Security	Resource consumption
Des	56 Guests	More quickly	Low	In
3DES	112-bit or 168-bit	Slow	In	High
Aes	128, 192, 256-bit	Fast	High	Low

Asymmetric algorithm (encryption key and decryption key are different)

Name	Maturity level	Security (depends on key length)	Operation Speed	Resource consumption
Rsa	High	High	Slow	High
Dsa	High	High	Slow	Can only be used for digital signatures
Ecc	Low	High	Fast	Low (less compute, less storage footprint, lower bandwidth requirements)

Hash algorithm Comparison

Name	Security	Speed
SHA-1	High	Slow
MD5	In	Fast

Comparison of symmetric and asymmetric algorithms

Name	Key Management	Security	Speed
Symmetric algorithm	More difficult, not suitable for the internet, generally used in internal systems	In	Fast several orders of magnitude (software encryption and decryption speed of at least 100 times times, can decrypt the number of M-bit data per second), suitable for large data volume encryption and decryption processing
Asymmetric algorithms	Key easy to manage	High	Slow, suitable for small data volumes plus decryption or data signing

Algorithm selection (from performance and security synthesis)

Symmetric encryption: AES (128-bit),

Asymmetric encryption: ECC (160-bit) or RSA (1024x768),

Message digest: MD5

Digital signature:DSA

Lightweight: TEA, RC series (RC4), Blowfish (infrequently changed keys)
Speed rankings (personal estimate, not verified): Idea <des <GASTI28<GOST<AES<RC4<tea<Blowfish

Simple encryption Design: Use the key to make the original or, substitution, substitution, shift

Name	Data size (MB)	Time (s)	Average Speed MB/s	Evaluation
Des	256	10.5	22.5	Low
3DES	256	12	12	Low
AES (256-bit)	256	5	51.2	In
Blowfish	256	3.7	64	High

Table 5-3 Single-key cryptographic algorithm performance comparison table

Name Implementation method Operation Speed Ann full sex Improvement measures Application situations des 40-56bit key General fully dependent on key, easy poor search attack dual, Sanchong des,aes     for hardware implementations Idea 128bit Key 8-Wheel Iteration More slowly Military grade, resistant to differential analysis and correlation Long word length of 32bit, the key is 256bit, using 2 modulus Plus, 2 +1 mode multiply suitable for ASIC design GOST 256bit key 32-Wheel Iteration More quickly Military grade Increase the number of iteration rounds s box can be random secret Dense selection for software implementation Blowfish 256-448bit Key,16-round iteration The fastest military-grade, adjustable security by changing the key length Suitable for fixed key occasions, not suitable for constant exchange keys and smart cards RC4 Variable Key length Fast DESl0 times Immunity to differential and linear attacks, highly nonlinear Key length relaxed to 64bit Simple algorithm, easy to program and implement RC5 Variable key length and iteration wheel count Speed can be based on of three parameters Values to select Resistance to linear attacks when wheel or above, by adjusting the word length, key lengths, and number of iterations can compromise security and speed Introduction of data-phase-change suitable for different lengths of microprocessors CASTl28 Variable key length,16-wheel Iteration More quickly resistant to linear and differential attacks Increase key length, form CAST256 Suitable for pc and UNIX Workstations

Common cryptographic algorithms
1, DES (Data Encryption Standard): symmetric algorithm, data encryption standards, faster, suitable for encrypting a large number of data occasions; 2, 3DES (Triple des): is based on des symmetric algorithm, a piece of data with three different keys three times encryption, the strength is higher, 3, RC2 and RC4: symmetric algorithm, with variable-length key to encrypt large amounts of data, faster than DES; 4, IDEA (International Data encryption algorithm) International data encryption algorithm, using 128-bit key to provide very strong security; 5, RSA: Invented by RSA, is a public key algorithm that supports variable-length keys, The length of the file block that needs to be encrypted is also variable, the asymmetric algorithm; 6, DSA (Digital Signature algorithm): Numerical signature algorithm, is a standard DSS (digital signature standard), strictly speaking, is not a cryptographic algorithm; 7, AES (Advanced Encryption Standard): Advanced encryption standards, symmetric algorithm, is the next generation of cryptographic algorithm standard, fast, high security level, in 21st century, an implementation of the AES standard is the Rijndael algorithm; 8, BLOWFISH, it uses a variable length key, up to 448 bits long, Run fast; 9, MD5: Strictly speaking, is not a cryptographic algorithm, can only be said to be a digest algorithm; 10, pkcs:the Public-key Cryptography Standards (PKCS) is a set of public key cryptography standards developed by RSA Data security Company and its partners, including a series of related protocols for certificate request, certificate renewal, certificate revocation table Publishing, extended certificate content, digital signature, digital envelope format, etc.11, SSF33,SSF28,SCB2 (SM1): The Secret of the state Password Bureau of the commercial algorithm, in the domestic civil and commercial, in addition to these are not allowed to use, the other can be used;
12.ECC(Elliptic Curves Cryptography): Elliptic curve cipher coding.

13. TEA(Tiny encryption algorithm)  simple and efficient encryption algorithm, encryption and decryption speed, simple implementation. But less secure thanDES,QQ has been using teaEncrypt

Name	Key length	Operation Speed	Security	Resource consumption
Des	56 Guests	More quickly	Low	In
3DES	112-bit or 168-bit	Slow	In	High
Aes	128, 192, 256-bit	Fast	High	Low

Comparison of various cryptographic algorithms