Lending blockchain accounts to others

1. blockchain itself solves the problem of large-scale cooperation between strangers, that is, strangers can cooperate with each other without mutual trust. So how to ensure the trust between strangers to achieve mutual consensus mechanism? The centralized system uses trusted third-party endorsements, such as banks. In the eyes of the common people, banks are reliable and trustworthy institutions. The common people can trust banks to solve real disputes. But how does a decentralized blockchain guarantee trust
in fact, blockchain uses the basic principles of modern cryptography to ensure its security mechanism. The knowledge system involved in the field of cryptography and security is very complicated. Here, I only introce the basic knowledge of cryptography related to blockchain, including hash algorithm, encryption algorithm, information digest and digital signature, zero knowledge proof, quantum cryptography, etc. Through this lesson, you can learn how to ensure the confidentiality, integrity, authentication and non repudiation of the blockchain using cryptography technology
basic course lesson 7 basic knowledge of blockchain security
1. Hash algorithm (hash algorithm)
hash function (hash), also known as hash function. Hash function: hash (original information) = summary information. Hash function can map any length of binary plaintext string to a shorter (generally fixed length) binary string (hash value)
a good hash algorithm has the following four characteristics:
1. One to one correspondence: the same plaintext input and hash algorithm can always get the same summary information output
2. Input sensitivity: even if the plaintext input changes slightly, the newly generated summary information will change greatly, which is greatly different from the original output
3. Easy to verify: plaintext input and hash algorithm are public, anyone can calculate by themselves, and whether the output hash value is correct
4. Irreversibility: if there is only the output hash value, the hash algorithm can never dece the plaintext
5. Conflict avoidance: it is difficult to find two plaintexts with different contents, but their hash values are the same (collision)
for example:
hash (Zhang San lent Li Si 100000 yuan for 6 months) = 123456789012
such a record as 123456789012 is recorded in the account book
it can be seen that hash function has four functions:
simplify information
it is easy to understand, and the information after hashing becomes shorter
identification information
you can use 123456789012 to identify the original information, and summary information is also called the ID of the original information
hidden information
the account book is a record like 123456789012, and the original information is hidden
verification information
if Li Si cheated that Zhang San only lent Li Si 50000 when repaying, both parties can verify the original information with the hash value of 123456789012 recorded before
hash (Zhang San lent Li Si 50000 for 6 months) = 987654321098
987654321098 is completely different from 123456789012, which proves that Li Si lied, Then the information can't be tampered
common hash algorithms include MD4, MD5 and Sha series algorithms, and Sha series algorithms are basically used in mainstream fields. Sha (secure hash algorithm) is not an algorithm, but a group of hash algorithms. At first, it was SHA-1 series, and now the mainstream applications are sha-224, SHA-256, sha-384 and sha-512 algorithms (commonly known as SHA-2). Recently, Sha-3 related algorithms have been proposed, such as keccak-256 used by Ethereum
MD5 is a very classic hash algorithm, but unfortunately, both it and SHA-1 algorithm have been cracked. It is considered by the instry that its security is not enough to be used in business scenarios. Generally, sha2-256 or more secure algorithm is recommended
hash algorithm is widely used in blockchain. For example, in blocks, the latter block will contain the hash value of the previous block, and the content of the later block + the hash value of the previous block will jointly calculate the hash value of the later block, which ensures the continuity and non tamperability of the chain< Encryption and decryption algorithm is the core technology of cryptography, which can be divided into two basic types: symmetric encryption algorithm and asymmetric encryption algorithm. According to whether the key used in the encryption and decryption process is the same or not, the two modes are suitable for different needs, just forming a complementary relationship, and sometimes can be combined to form a hybrid encryption mechanism
symmetric cryptography (also known as common key cryptography) has the advantages of high computational efficiency and high encryption strength; Its disadvantage is that it needs to share the key in advance, which is easy to leak and lose the key. The common algorithms are des, 3DES, AES and so on
asymmetric cryptography (also known as public key cryptography) is different from the encryption and decryption key, and its advantage is that it does not need to share the key in advance; Its disadvantage is that it has low computational efficiency and can only encrypt short content. Common algorithms include RSA, SM2, ElGamal and elliptic curve series. Symmetric encryption algorithm is suitable for the encryption and decryption process of a large number of data; It can't be used in signature scenario: and it often needs to distribute the key in advance. Asymmetric encryption algorithm is generally suitable for signature scenario or key agreement, but it is not suitable for large amount of data encryption and decryption< Third, information digest and digital signature
as the name suggests, information digest is to hash the information content to obtain a unique digest value to replace the original and complete information content. Information digest is the most important use of hash algorithm. Using the anti-collision feature of hash function, information digest can solve the problem that the content has not been tampered
digital signature is similar to signing on paper contract to confirm contract content and prove identity. Digital signature is based on asymmetric encryption, which can be used to prove the integrity of a digital content and confirm the source (or non repudiation)
we have two requirements for digital signature to make it consistent with our expectation for handwritten signature. First, only you can make your own signature, but anyone who sees it can verify its validity; Second, we want the signature to be only related to a specific file and not support other files. These can be achieved by our asymmetric encryption algorithm above
in practice, we usually sign the hash value of information instead of the information itself, which is determined by the efficiency of asymmetric encryption algorithm. Corresponding to the blockchain, it is to sign the hash pointer. In this way, the front is the whole structure, not just the hash pointer itself< Zero knowledge proof means that the verifier can make the verifier believe that a certain conclusion is correct without providing any additional information to the verifier
zero knowledge proof generally meets three conditions:
1. Completeness: authentic proof can make the verifier successfully verify
2. Soundness: false proof can not make the verifier pass the verification
3. Zero knowledge: if you get proof, you can't get any information other than the proof information from the proof process< With more and more attention paid to the research of quantum computing and quantum communication, quantum cryptography will have a huge impact on the information security of cryptography in the future
the core principle of quantum computing is that qubits can be in multiple coherent superposition states at the same time. Theoretically, a large amount of information can be expressed by a small number of qubits and processed at the same time, which greatly improves the computing speed
in this way, a large number of current encryption algorithms are theoretically unreliable and can be cracked, so the encryption algorithm has to be upgraded, otherwise it will be broken by quantum computing
as we all know, quantum computing is still in the theoretical stage, which is far from large-scale commercial use. However, the new generation of encryption algorithms should consider the possibility of this situation.

2. We must be vigilant. Last night, CCTV news disclosed that the Internet Supervision Bureau has monitored 755 air coins, of which 102 are pyramid selling coins, all of which are harmful

3.

Blockchain itself is not illegal, but if it is used illegally, it is illegal

Li Bin, deputy director of Chongqing big data application and development administration, said that as a disruptive innovative frontier technology in the field of big data intelligence, the Chongqing municipal government attaches great importance to active layout, and the municipal government and Yuzhong District Government jointly build a blockchain base. In the second half of last year, the government issued the opinions on accelerating the cultivation and innovative application of blockchain instry, It has officially launched the construction of a place for strategic innovation of blockchain

while actively encouraging the technological progress and instrial development of blockchain, we will resolutely prohibit the illegal use of blockchain technology in accordance with the requirements of relevant national policies

at present, China's blockchain technology and application continue to innovate, and are graally applied in supply chain finance, credit reference, proct traceability and other fields, with huge development space. As a new technology, if blockchain wants to realize large-scale practical application, it must strengthen the cooperation of instry, University, research and application, and promote the continuous development and maturity of technology and application

since 2017, the development of blockchain technology has aroused the deep concern of the government, enterprises and other sectors. Because of its decentralized, tamperable and traceable characteristics, blockchain attracts investors to add weight to this new technology field. For the previous hot speculation of blockchain technology, the cognition of it and investment circles has become increasingly rational

extended data

"Regulations on the management of blockchain information services (Draft)"

Article 9 blockchain information service providers and users shall not use blockchain information services to engage in activities that are prohibited by laws and regulations, such as endangering national security, disrupting social order, and infringing the legitimate rights and interests of others, and shall not use blockchain information services to proce and use blockchain information services Copy, publish and disseminate information prohibited by laws and regulations

Article 13 a blockchain information service provider shall, as the case may be, take such measures as warning, limiting functions, closing account numbers, etc. for users of blockchain information services who violate laws, regulations and service agreements, so as to timely eliminate illegal information, prevent information diffusion, keep relevant records, and report to relevant competent authorities

Article 18 If a blockchain information service provider, in violation of the provisions of Article 9 of these Provisions, makes, copies, publishes and disseminates information content prohibited by laws, regulations and relevant national regulations, the Internet Information Office of the state, provinces, autonomous regions and municipalities directly under the central government shall give a warning and order it to correct within a time limit according to law

if the circumstances are serious or refuse to correct, the service shall be ordered to suspend, and a fine of not less than 5000 yuan but not more than 30000 yuan shall be imposed, until the relevant departments close the service according to law. If a crime is constituted, criminal responsibility shall be investigated according to law

If a blockchain information service user violates the provisions of Article 9 of these provisions and makes, copies, publishes and disseminates information content prohibited by laws and regulations and relevant national regulations, the Internet Information Office of the state, provinces, autonomous regions and municipalities directly under the central government shall deal with it in accordance with relevant laws and administrative regulations

Article 19 If a blockchain information service provider violates the provisions of Article 6 of these provisions and fails to mark its record number on its network platform, the Internet Information Office of the state, provinces, autonomous regions and municipalities directly under the central government shall order it to make corrections within a time limit according to its ties, and if it refuses to make corrections, it shall be given a warning and fined not less than 5000 yuan but not more than 10000 yuan

Article 20 If a blockchain information service provider violates the provisions of paragraph 1 of Article 4 of these provisions and fails to go through the filing proceres in accordance with these Provisions, the Internet Information Office of the state, provinces, autonomous regions and municipalities directly under the central government shall order it to make corrections within a time limit according to its ties, and if it refuses to make corrections or if the circumstances are serious, it shall be given a warning and fined not less than 10000 yuan but not more than 30000 yuan

Article 21 if the blockchain information service provided by the blockchain information service provider has potential information security risks, the Internet Information Office of the state, provinces, autonomous regions and municipalities directly under the central government shall, according to its ties, order it to rectify and suspend the service within a time limit, and continue to provide information services until it meets the relevant requirements of laws and regulations and national mandatory standards after rectification

if the blockchain information service provider violates the provisions of Article 4, paragraph 2, Article 8, Article 11, Article 12, Article 15 and Article 16 of these Provisions, the state and local Internet Information Office shall give a warning and order it to correct within a time limit according to its ties; If the circumstances are serious or if he refuses to make corrections, he shall be ordered to suspend service and be fined not less than 5000 yuan but not more than 30000 yuan; If a crime is constituted, criminal responsibility shall be investigated according to law

if the blockchain information service provider violates the provisions of Articles 10, 13 and 14 of these Provisions, it shall be handled by the Internet Information Office of the state, provinces, autonomous regions and municipalities directly under the central government in accordance with the provisions of the network security law of the people's Republic of China

4. The core of blockchain + is to graally eliminate all instries that need intermediary to do trust. At present, many central nodes and service platforms of the Internet are essentially trust mediators. Users can do shopping, traveling, ordering, paying and so on through the trust intermediaries such as Taobao, Didi, excellent step, American group, Alipay and WeChat payment.

but the Internet has never been static, and continuous evolution is the norm. In the future, people will have new trust dependence. Because the records of the blockchain can not be tampered with and are authentic, people's trust in the blockchain graally exceeds that of the centralized company. With the joint efforts of many blockchain enterprises and some traditional instries, the world will graally transition from a centralized trust driven to a system driven by algorithms and data. When the centralized trust intermediary is graally weakened, the system represented by blockchain will graally take over the operation mode of the whole world, and finally form the "disintermediated" system trust
therefore, blockchain is not only a technology, but also a story about the paradigm shift of world operation. Although the story is still a little far away, it has sprouted and initially developed

blockchain Internet will start from the instries most closely related to trust and traceability, and graally expand and expand until most instries are blockchain oriented and blockchain +
Puyin is a high-quality Tibetan tea asset, which is stored, identified, evaluated and authorized by three parties. It is a standard digital currency issued through encryption and digitization. Puyin implements the concept of "white paper on standard digital currency" in strict accordance with its operation guidelines, and sets a standard for asset digitization

5. To be sure, No. This is not a low configuration computer. This is the tablet configuration. You can understand it as the tablet with a keyboard,
if you don't know how to ask, please accept if you are satisfied

6. There are risks. Why is the account unfrozen
do you have any illegal operations
if you don't do anything, how can your account be frozen
can blockchain software bring you excess revenue
is it worth $50000
money will not be lost in vain. The money in your hand is real.

7. There are risks, of course

8. Some can, some can't, some projects don't have regulations, can't have more than one number, the regulations can't, that will be blocked.

9. Unknown_Error