Digital currency and digital watermark

1. They don't mean the same thing at all. Digital China refers to the statistical data of China's national economy and people's livelihood. digital currency, however, is only currency or money represented by computer program code.

2.

1. The concept range is different. bitcoin is a kind of digital currency, and the concept of digital currency covers bitcoin

However, some digital currencies have independent issuers

The biggest difference between bitcoin and other virtual currencies is that the total quantity of bitcoin is very limited and it has a strong scarcity. The monetary system used to have no more than 10.5 million in four years, after which the total number will be permanently limited to 21 million

digital currency is abbreviated as digiccy, which is the abbreviation of "digital currency" in English. It is an alternative currency in the form of electronic currency. Both digital gold coin and cryptocurrency belong to digiccy. Bitcoin is a digital currency

digital currency is different from the virtual currency in the virtual world, because it can be used for real goods and services transactions, not limited to online games. The early digital currency (digital gold currency) is a form of electronic currency named after the weight of gold

today's digital currencies, such as bitcoin, lettercoin and ppcoin, are electronic currencies created, issued and circulated by means of check sum cryptography. It is characterized by the use of P2P peer-to-peer network technology to issue, manage and circulate currency. In theory, it avoids bureaucratic examination and approval, so that everyone has the right to issue currency

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illegal digital currency

in recent years, "virtual currency" represented by bitcoin, Ethernet currency and Leyte currency has been traded centrally on some Internet platforms. With the help of financial technology, the price of these "currencies" has graally spread to investment, financing and other financial fields, which has aroused wide attention from all walks of life

not long ago, the people's Bank of China and other seven ministries and commissions jointly issued the announcement on preventing the financing risk of token issuance, which clearly regulated the relevant behaviors. Experts pointed out that "virtual currency" is not legal tender (legal currency) issued by monetary authorities, but a specific virtual commodity in essence

therefore, it is undoubtedly a great legal and economic risk to think that "virtual currency" has or will have the nature of legal tender and to carry out speculation, network fund-raising, lending and financing

3. First of all, digital currency is not the national legal tender, but the "alternative currency in the form of electronic currency", such as bitcoin, ecell currency and ether currency. Currency digitization is to represent the common currency with numbers, and the number corresponds to the national legal tender. There is a big difference between the two.

4. Currency digitalization is like WeChat Alipay, and bankcard pays
1. digital currency facing two risks. The first is the technical level. Digital currency relies on blockchain technology and a system, which will make it suffer from security impact, such as hacker attacks on computer systems. We have seen many practical problems in this process< Another risk of digital currency is credit risk. Because there are middlemen in digital currency transactions, these middlemen are different from real organizations. In reality, organizations can be seen and felt, but the middlemen of digital currency are on the Internet, so the risk is greater
3. Digital currency has the characteristics of anonymity, quickness and irrevocability. In addition, bitcoin and other digital currencies have high circulation in the world, so many criminals use digital currency as a new money laundering channel. Moreover, there are many different ways to realize money laundering through digital currency. Generally speaking, the probability of new money laundering being found and investigated is lower than before. Many countries have no effective means and technology to combat money laundering through digital currency. These factors lead to criminals prefer this way of money laundering
investment is risky and business should be cautious

5.

1、 Different definitions:

1. Electronic currency:

refers to the currency paid by electronic means

2. Digital currency:

is a virtual currency based on node network and digital encryption algorithm

Electronic currency: Based on computer technology, it can be widely used in the fields of proction, exchange, distribution and consumption. It has many functions such as financial savings, credit and non cash settlement

2. Digital currency:

e to some open algorithms, digital currency has no issuers, so no one or institution can control its issuance; Because the number of algorithm solutions is fixed, the total amount of digital currency is fixed, which fundamentally eliminates the possibility of inflation caused by the overuse of virtual currency; Because the transaction process needs the approval of each node in the network, the transaction process of digital currency is safe enough

Third, the same point:

the circulation mode of e-money and digital money is two-way circulation

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e-money is the virtualization of the value scale of real money and the function of payment means. It is a kind of money without monetary entity. Electronic currency is an invisible currency based on highly developed electronic technology

the value of e-money is transferred from the consumer to the seller through the sales terminal, and then the seller redeems the money. The e-money held by the merchant is sent to the e-money issuer to redeem the money, or to the bank. The bank debits the corresponding amount on its account, and then the bank settles with the issuer through the clearing institution

electronic money can transfer money value directly among the holders. It does not require the intervention of third parties, such as banks. This is also the essential difference between electronic money and traditional cash card and transfer card. p>

6. Digital currency is a relatively large concept. However, what we usually say about digital currency generally refers to the encrypted digital currencies such as bitcoin, Ruitai coin and Laite coin
there is no essential difference between virtual currency and digital currency, but it is only called differently. Digital currency is generally called high-end, and professionals generally call it digital currency. Virtual currency is the most popular term, which is generally used by those who don't know much about it.

7.

1、 Different definitions:

1. Digital watermark:

a kind of protection information embedded in carrier file by computer algorithm

2. Watermark:

refers to the traditional method of printing paintings with woodcut in China

Digital watermark: it embeds some identification information (i.e. digital watermark) directly into the digital carrier (including multimedia, document, software, etc.) or indirectly represents (modifying the structure of a specific area), and does not affect the use value of the original carrier, and is not easy to be detected and modified again

2. Watermark:

mixing pigment with water, no oil, different from the general color printing method, so it is called "watermark". Also called "watermark woodcut"

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according to the characteristics of watermarking, digital watermarking can be divided into robust watermarking and fragile watermarking. Robust watermarking is mainly used to identify right information in digital works. This watermarking technology is used to embed the creator's and owner's identification information or the buyer's identification (i.e. serial number) in the data of multimedia content

in case of right dispute, the creator's or owner's information is used to identify the right owner of the data, while the serial number is used to track the user who violates the agreement and provides multimedia data for piracy. Digital watermarking for right protection requires strong robustness and security. In addition to surviving in general image processing, it also needs to be able to resist some malicious attacks

8. Using digital signature, the following two points can be confirmed:
(1) guarantee that the information is sent by the signer's own signature, and the signer can't or can't deny it
(2) guarantee that the information has not been modified since it was issued and the issued document is true
the specific method of digital signature is as follows:
(1) calculate a fixed number of message digest according to hash algorithm agreed by both parties. Mathematically, as long as any bit in the message is changed, the recalculated message digest value will not match the original value. In this way, the message can not be changed
(2) the digest value of the message is encrypted with the sender's private key, and then sent to the receiver together with the original message. The resulting message is called digital signature
(3) after receiving the digital signature, the receiver uses the same hash algorithm to calculate the digest value of the message, and then compares it with the digest value of the message decrypted with the sender's public key. If the digest value is equal, it means that the message really comes from the sender

digital watermarking is to embed some identification information (i.e. digital watermark) directly into digital carriers (including multimedia, documents, software, etc.), but it does not affect the use value of the original carrier, and is not easy to be detected or noticed by people's perception system (such as visual or auditory system)

difference:
encrypted information is stored in the media, but it does not damage the original information of the media.

9. Video watermarking refers to those movies on the Internet. When you download or watch them online, you will see many irrelevant words or logos. For example, Youku's videos all have a Youku logo, and some downloaded movies often have a line of words floating by. The original video is not available, and the website adds it for publicity. That's the watermark

digital watermark technology embeds some label information related or not related to multimedia content directly into the multimedia content, but it does not affect the use value of the original content, and is not easy to be detected or noticed by people's perception system. Through the information hidden in the multimedia content, we can confirm the content creator, buyer, or whether it is true and complete. Digital watermarking is an important research direction of information hiding technology
in daily life, in order to identify the authenticity of banknotes, people usually point the banknotes at the light source and find that there is clear image information in the real banknotes, which is known as "watermark".