The Design and Realization of Digital Signature Bad on RSA说字组词
RSA algorithms is introduced
RSA public key cryptography. So-called public key cryptography system is to u different encryption and decryption key keys, is a "known encryption key is deduced by declassified in calculations is key to be done" password system.
In a public-key cryptosystem, encryption key (i.e. public key) PK is the public information, and decryption key (namely, the private key) SK is needed to remain confidential. Encryption algorithm E and decryption algorithm D also are in the open. Although the cret key SK is by public key PK decision, but cannot PK calculated according to SK. It is bad on this theory, appeared in 1978 the famous RSA algorithms, it is usually into a pair of Mr RSA keys, one of which is kept cret key, save by urs; Another for public key, can be made public, and even can be registered in the network rver. In order to improve the crecy intensity, RSA keys at least 500 bits long, generally recommend using 1024 bits. This makes the calculation amount of encryption is very large. To reduce the computational complexity, nding the information, often USES traditional encryption methods and public key encryption method unifies means, that information with the improved DES or IDEA dialogue key encryp
tion, and u the RSA encryption keys and information the dialogue. Each other after receiving information, with different keys decryption and can check the information.
RSA algorithms is the first not only can be ud for encryption but also can be ud for digital signature algorithm, and it is also easy to understand and operation. RSA is most widely studied public key algorithm, and put forward to the now from more than 30 years, experienced the test of all kinds of attacks, for the people to accept gradually, generally, is now one of the most outstanding public key solutions.
The safety of the RSA
RSA curity depends on the larger decomposition, but whether or not equal to tarsus decomposition theory has been failed to get the certificate, and for no proof that break RSA will need to be larger decomposition. Assuming there are a large without
琢磨的意思decomposition algorithm, it must be larger decomposition algorithm can be modified. At prent, some variant of RSA algorithms have been proved equivalent to tarsus decomposition. Anyway, the decomposition n is the most obviously method of assault. Now, people already can break down more than 140 decimal big primes. Therefore, must choo a big modulus n some, for application is up.
RSA speed
Becau of the large is calculated, make the fastest RSA than DES 100 times on slow, whether software or hardware implementation. Speed has been the defects of RSA. Generally speaking only for a few data encryption.
RSA's chon-ciphertext attack
RSA in chon-ciphertext before the attack is weak. Generally the attacker is will certain information is the camouflage (Blind), let the private key with the entity to sign. Then, after calculation can get what it wanted information. In fact, attack the same weakness are using, that is such a fact that have been retained the multiplication of the input structure: (XM) ^ d = X ^ d * M ^ d mod n front have already mentioned, the inherent problems from the public key cryptography is the most uful features-everyone can u public key. But from the algorithm can't solve the problem, the main measures are two: one is the good public key agreement, guarantee the process not produce any other entity entity of the information the decryption, you know nothing wrong information signature; The other One is never nt to strangers random document signature, the first to u One sign of a document for-Way HashFunction HASH processing, or u at the same time different signature algorithm.苦瓜炒蛋的做法
RSA encryption algorithm faults
⑴produce key is very troublesome, produced by a prime technical limitations, so hard to do it once a cret. ⑵curity, the safety of RSA depends on the large factor decomposition, but did not prove theoretically decipher the difficulty of tarsus and RSA decomposition difficulty equivalent, and most people tend to academic password factor decomposition is not NPC problem. At prent, people already can break down more than 140 decimal big primes, it is required to u more long key, speed, more slowly; Moreover, the people are actively looking for attack RSA methods, such as chon-ciphertext attack, general attackers will certain information is the camouflage (Blind), let the private key with the entity to sign. Then, after calculation can get what it wanted information. In fact,
attack the same weakness are using, that is such a fact that have been retained the multiplication of the input structure: (XM) d = Xd * Md mod n front have already mentioned, the inherent problems from the public key cryptography is the most uful features-everyone can u public key. But from the algorithm can't solve the problem, the main measures are two: one is the good public key agreement, guarantee the process not produce any other entity entity of the information the decryption, you know nothing wrong information signature; The other One is never nt to strangers random document signature, the first to u One sign-Way Hash Function of document for Hash pro电路知识
cessing, or u at the same time different signature algorithm. In addition to using public modulus, people also try s ome u decryption index or φ (n) and so on attack.⑶ speed too slow, becau the grouping of RSA too large length, to ensure safety, n at least 600 bitx above, make the operation cost is high, especially at a slower speed, a symmetric cryptosystem veral orders of magnitude slower; Along with the development of the larger decomposition technique, the length is increasing, go against the standardization of data format. At prent, the SET (Secure Electronic Transaction) agreement with 2048 bits long requirements CA keys, other entity USES 1024 bit key. In order to speed, at prent the widely u of single, the method of using a combination of public key password, complementary advantages and disadvantages: ChanYao password encryption speed, people u it to encrypt a long documents, and then using the RSA encryption to give document, extremely good solve the problem of ChanYao password key distribution.
Modern cryptography has become the core of information curity technology, cryptography, is the communication curity confidential subject rearch, that is, to study the type of cret information transmission of transformation in order to prevent the third party to steal information. Cryptography include two branches: password code to learn and password analytics. Password code to learn the main information exchange, to protect information in the channel's relay in to steal, decryption and u香砂六君子
method, and the password analysis learning is and password code learning instead, it mainly studies how to analyze and crack password. Both between both opposition to each other and promote each other. The classification of the password system has a lot of, one of them is bad on encryption algorithm and decryption keys ud algorithms are same, password system can be divided into symmetrical encryption system (ChanYao password system) and asymmetric encryption system (public key cryptosystems), the two password system each
have their own advantages and disadvantages, so now USES two hybrid. Public key cryptosystems features are: the receiving party B produces a pair of keys (PK and SK); PK public, SK confidential; PK from launch SK is very difficult; A and B both sides communication, A in any way obtained B public key, u the B public key encryption information, encrypted information can be obtained by any unsafe channel nt. B received ciphertext information, with their own private key recovering the decryption plaintext. Public key cryptography system to ensure the curity of information have become the key technology. RSA public key cryptosystems so far or a recognid as safe system. RSA public key encryption algorithm is the first can ud for data encryption can also be ud as a digital signature algorithm. It is easy to understand and operation, is also very popular. As more commercial application and standardization work, RSA has become the most reprentative of the p
ublic key encryption technology. VISA, MasterCard, IBM, Microsoft and other companies for the safety of Electronic trading work standard (Secure Electronic Transactions, SET) adopt the standard RSA algorithms, this makes the RSA in our life almost everywhere. Online transactions encrypted connection, the bank on the net identity authentication, all kinds of credit card the u of digital certificate, intelligent mobile phone memory card and validation of chips and so on the function, most u RSA technology.
In 1995, has been put forward a very unexpected attack way: if E younger sister to huang hardware are fully know, and know it to some specific message when the time needed to encrypt words, so she can be quickly is deduced from the d. This attack will be established the way, mainly becau of the encryption on the mode of the index when computing is a bit a bit, and bits of 1 spent than a yuan for 0 computation of a operation, so if you can get more information and its encryption of time, will have a chance to launch the private key content. The most popular attack on RSA is generally larger factor decomposition bad on. In 1999, the RSA-155 (512 bits) be successful decomposition, spent five months time (about 8000 MIPS years) and 224 CPU hours in a 3.2 G the central memory Cray C916 finished on the computer. In 2002, the RSA-158 was also success factor decomposition. On December 12, 2009, Numbers for RSA-768 (768 bits, 232 digits) number also be successful dec
最后的常春藤叶omposition. Beijing time February 15 morning news, according to the New York times reported Tuesday, European and American mathematicians and cryptographers accidental discovery, at prent is widely spoken all
over the world's public key encryption algorithm RSA existence of loopholes. They found that, in 7 million the experiment of 27000 sample public key and not according to the theory of randomly generated. That is, maybe someone can find out the cret of produce public key prime Numbers. This rearch project was made by the independent cryptographers James P.H ughes and Dutch mathematician Arjen k. Lenstra lead. Their report said: "we found the vast majority of the public key all is according to the theory of generation, but every one thousand public key will have two unsafe." The report says, to prevent someone USES the vulnerability, a public key from the public access databa has been removed. To ensure the curity of the system, the website needs to be in the terminal to change.
Over the years, RSA mainly focus on information curity market in veral fields, is also have distinguishing feature each field. In the identity authentication field, RSA attention to many online trading enterpri including financial, arch, and industry, the ur to the extent of the identity authentication concern obviously different. Another fishing, Trojan than before more widespread. Onli
ne identity authentication, the growth is strong fraud. In addition, the enterpri internal control, at prent, China is still in the process of maturity. In the data leak in some new "Trojan RSA rvices to society and to the strong identity authentication, also have some new business breakthrough.
The financial industry in anywhere in the world, there are the highest safety risk industry, whether the reality of crime or cyber crime, financial is a sweet BoBo. Along with the development of the network bank, financial industry to information curity solutions needs always very strong, the financial industry is the largest RSA development space, and in the future for a period of time will still is. How to keep the financial industry information curity, prevent data leak, and deal with the financial rvices, and become the focus of future business development RSA.
Digital signature is introduced
Digital signature, is the only information to produce the nder of the others can't fake a digital string, the string is also a number of information of the nder nds information a valid proof of authenticity.百无一用
对牛谈情Digital signature is symmetrical encryption technology and the application of digital technology.
Digital signature of the file is easy to verify the integrity of the (don't need at the
