flower

2.

BTC (business to customer)

also known as B2C, e-commerce according to a classification of trading partners, that is, commercial institutions to consumers of e-commerce. This form of e-commerce is generally based on the network retail instry, mainly with the help of the Internet to carry out online sales activities

B2C mode is the earliest e-commerce mode in China, marked by the formal operation of 8848 online mall. B2C means that enterprises provide consumers with a new shopping environment through the Internet - online store, where consumers shop online and pay online

because this mode saves the time and space of customers and enterprises, and greatly improves the transaction efficiency, especially for busy office workers, this mode can save valuable time

two BTB (business to business)

also known as B2B, refers to a kind of Internet market, which is the marketing relationship between enterprises. It combines the intranet with customers through B2B website, and provides better service for customers through the rapid response of the network, so as to promote the business development of enterprises. In recent years, B2B develops rapidly and tends to be mature

three otos (online to offline)

also known as o2o, namely "online to offline". The core of the business model of oto is very simple, which is to bring online consumers to real stores, pay online to buy offline goods and services, and then enjoy offline services

extended materials:

e-commerce is a business activity with information network technology as the means and commodity exchange as the center; It can also be understood as the activities of trading activities and related services in the form of electronic transactions on the Internet, intranet and value-added network. It is the electronization, networking and informatization of all aspects of traditional business activities

e-commerce usually refers to a wide range of business and trade activities all over the world, in the Internet open network environment, based on Browser / server application mode,

buyers and sellers do not meet each other to carry out a variety of business activities, to achieve consumer online shopping, online transactions and online electronic payment between merchants, as well as a variety of business activities, trading activities Financial activities and related integrated service activities are a new business operation mode

governments, scholars and business people in various countries have given many different definitions according to their own status and different angles and degrees of participation in e-commerce. E-commerce is divided into ABC, B2B, B2C, C2C, B2M, M2C, B2A (B2G), C2A (C2G), o2o, etc

At the same time, network marketing is also a proct of e-commerce, and for network marketing, it is necessary to make a good network marketing plan before doing it, so as to facilitate the implementation of the plan

since October 1, 2018, the Ministry of finance, the State Administration of Taxation, the Ministry of Commerce and the General Administration of customs have jointly issued the new regulations on tax exemption for e-commerce export enterprises in the comprehensive pilot zone of cross border e-commerce

3. BTC" This situation indicates that your vehicle has light failure (the light is not on), please check the high beam, low beam, driving lights (front and rear 4)
steering lights (front and rear 4) and brake lights for failure. After the fault is repaired (changing the bulb), the fault light on the instrument panel will go out.

4. In the process of learning blockchain, you will hear the word "double flower", which means double payment, or more directly, a sum of money has been spent twice. In this article, we will briefly analyze why there are double flowers and how bitcoin can avoid double flowers

in the traditional transaction, there is no double spending problem because there is a centralized institution such as a bank: every payment will be dected from your bank account, and all details will be recorded in the bank. But in bitcoin, because there is no concept of account, utxo is introced, that is, no transaction output is spent. Because there is no guarantee from centralized institutions such as banks, when a transaction occurs, there may be a risk of double spending: for example, a has a bitcoin, and then he constructs two transactions T1 and T2 at the same time to spend the bitcoin, one of which is given to B, to buy a suit from B, one is given to C, and to buy a pair of shoes from C. If we do not introce some mechanism to avoid this situation, bitcoin, as a digital currency, will not have any meaning of existence. Next, let's analyze how bitcoin can prevent this "double flower" attack

(1) normal situation

first of all, let's look at the normal situation. To put it bluntly, most of the time, the consensus mechanism of blockchain can nip Shuanghua in the bud. Let's illustrate with the above examples:

suppose that a constructs two transactions T1 and T2, and transfers its own value of 1btc utxo to B and C respectively, in an attempt to obtain benefits from B and C at the same time. Then a broadcasts the two constructed transactions to the network almost at the same time

suppose that the miner node in the network receives the transaction T1 first, and finds that the source of funds for the transaction has not been spent, so it adds T1 to its own memory transaction pool and waits to be packaged into the block

in most cases, the miner node will receive transaction T2 soon. At this time, the miner node will refuse to process the transaction because the transaction input that T2 points to is the same as T1 that has been added to the transaction pool. Other miner nodes in the network are similar, so a's attempt to double flower is stillborn

(2) bifurcation

the above is normal, but there are also abnormal cases to consider: suppose that the miner nodes M1 and M2 dig out the block almost at the same time, and unfortunately M1 only receives transaction T1 when digging in the block, while M2 only receives transaction T2 when digging in the block, so transaction T1 and T2 are packed into two blocks respectively. Because these two blocks were g out at about the same time, resulting in the bifurcation of the blockchain:

some nodes in the network (which may be close to M1) received the block blk1 packed by M1 first, so they used the block to extend their own blockchain, while other nodes (which are close to M2) received the block blk2 packed by M2 first, and used the block to extend their own blockchain, So the whole blockchain network

5. As for the impact of various events on the price of bitcoin, there are four types of such events
political events: most of these events involve the government's attitude towards bitcoin, such as the Federal Reserve's recognition of bitcoin as a financial instrument, Germany's recognition of bitcoin as a currency, China's prohibition of financial institutions from participating in bitcoin trading, and Russia's prohibition of using bitcoin and participating in bitcoin mining. Although bitcoin itself is a neutral technology, it is not affected by politics, but the price of bitcoin will fluctuate dramatically because of such events. So far, this is the biggest factor affecting the price of bitcoin
exchange events: Although bitcoin is a decentralized currency, bitcoin transactions mainly take place in centralized exchanges. Since the birth of bitcoin, many exchanges have been stolen. For example, mtgox, the largest Japanese exchange, lost 700000 bitcoins. Recently, bitfinex, the Hong Kong exchange, lost 120000 bitcoins. Bitstamp, the Slovenian exchange, was attacked and lost 19000 bitcoins. Whenever such an event occurs, the risk of bitcoin trading increases sharply, and bitcoin will often usher in a larger decline
financial events: such events often come from the instability of the real financial world, such as the default of the Central Bank of Cyprus, which leads to zero savings of more than 100000 euros of the country's depositors, serious devaluation of Ukraine's currency under the pressure of war, and brexit of the UK, which weakens the stability of the euro area. Bitcoin, as a safe haven asset, is gaining more and more market recognition. At present, the trading volume of bitcoin in the world has exceeded that of gold ETF, and the instability of fiat money has caused the continuous rise of bitcoin
Technical events: as a decentralized open source network protocol, bitcoin's code is far from perfect. There have been several crises in bitcoin's protocol. For example, a certain upgrade of bitcoin protocol has not been unanimously recognized by the whole network. In the end, there is a double flower problem. The scalability of bitcoin's transaction makes it easy for hackers to attack and steal, At one time, it forced several bitcoin exchanges to suspend trading. Recently, there has been a heated debate about expansion in the bitcoin community, and no effective solution has been available, which has cast a shadow on the future of bitcoin. Whether the bitcoin protocol can continue to evolve is a long-term impact on the price of bitcoin.

6. You are right. Indeed, it will be rolled back. If the transaction is unfortunately packaged on the fork, the transaction is likely to be cancelled after the main chain is synchronized

the reason why we need six confirmations is that it is more difficult to obtain the optimal solution (to prevent single node fraud). One block may also be able to get an optimal solution, and it is basically impossible to get six blocks together. It has nothing to do with bifurcation

7.

Transaction mode of bitcoin

bitcoin is e-cash similar to e-mail, and both parties need "bitcoin wallet" similar to e-mail and "bitcoin address" similar to e-mail address. Just like sending and receiving e-mail, the remitter pays bitcoin directly to the other party through a computer or smart phone according to the recipient's address. The following table lists some websites that download bitcoin wallets and addresses for free

a bitcoin address is a string of about 33 characters long, consisting of letters and numbers, always starting with 1 or 3, such as & quot& quot; Bitcoin software can generate address automatically, and it doesn't need to exchange information online, so it can be offline. More than 2 bitcoin addresses are available. Figuratively speaking, there are about two grains of sand in the world. If there is an earth in each grain of sand, then the total number of bitcoin addresses far exceeds the number of all the sand on all these "earths"

the bitcoin address and private key appear in pairs, and their relationship is just like the bank card number and password. A bitcoin address is like a bank card number, which records how much bitcoin you have on it. You can generate bitcoin address at will to store bitcoin. When each bitcoin address is generated, a corresponding private key of the address will be generated. This private key proves that you have ownership of the bitcoin at that address. We can simply understand the bitcoin address as the bank card number, and the private key of the address as the password of the corresponding bank card number. Only when you know the bank password can you use the money on the bank card number. Therefore, please keep your address and private key when using bitcoin wallet

after the transaction data of bitcoin is packaged into a "data block" or "block", the transaction is initially confirmed. When a block is linked to a previous block, the transaction is further confirmed. After six block confirmations in a row, the transaction was irreversibly confirmed. Bitcoin P2P stores all transaction history in a "blockchain.". The blockchain continues to extend, and once new blocks are added to the blockchain, they will not be removed. Blockchain is actually a distributed database composed of a group of scattered client nodes and all participants, which is a record of all bitcoin transaction history. Nakamoto predicts that when the amount of data increases, users hope that not all the data will be stored in their own nodes. In order to achieve this goal, he uses the hash function mechanism. In this way, the client will be able to automatically eliminate those parts that it will never use, such as some very early bitcoin transactions