"As long as you have a digital wallet with digital RMB on your mobile phone, you don't even need
"As long as you have a digital wallet with digital RMB on your mobile phone, you don't even need the Internet. As long as the mobile phone has electricity and the two mobile phones touch each other, digital currency in one person's digital wallet can be transferred to another person. "
Isn't it amazing? We are used to the era of various network connections. Does this offline payment technology feel quite advanced?
Recently, the Shenzhen Municipal People's Government and the People's Bank of China launched a pilot project of digital RMB red envelopes. As a technician, I want to know how to realize double offline payment, and where is this digital RMB?
1. What is digital RMB?
Digital RMB, issued by the People's Bank of China, is the legal tender with the ability of national credit endorsement and legal compensation.
Compared with virtual currencies such as Bitcoin, digital RMB is legal tender, equivalent to legal tender, and has the highest effectiveness and security. Bitcoin is a virtual asset, which has no value basis, does not enjoy any sovereign credit guarantee, and cannot guarantee the stability of its value. This is the most fundamental difference between digital currency, the central bank and bitcoin.
1. Double offline payment. Like paper money, it can meet the needs of electronic payment in places with poor network signals such as airplanes, cruise ships and underground parking lots;
2. The security is higher. If theft really happens, for real-name wallets, digital RMB can provide loss reporting function;
3. Multi-terminal selection. People who are unwilling or unable to use smart phones can choose IC cards, function machines or other hardware;
4. Multi-information intensity. According to the intensity of mastering customer information, digital RMB wallets are divided into several grades. For large payment or transfer, real-name registration system wallet with high information density must be used;
5. Point-to-point delivery. Through the way of digital currency smart contract, the delivery from fixed point to person can be realized. People's livelihood funds can be distributed to people's digital wallets, eliminating the possibility of false reporting, interception and misappropriation;
2. What's the difference between digital RMB and e-wallets such as Alipay and WeChat?
First, digital RMB is legal tender, and no institution or individual can refuse it, while WeChat payment and Alipay are just a payment method.
For example, if you pay for shopping in the mall, do you think you can pay by WeChat? The shopkeeper told you no, I only support Alipay here, and there's nothing you can do. But it's different if you pay in digital RMB. If the owner doesn't accept it, he can call the police directly.
Second, third-party Internet payments such as Alipay and WeChat Payment require devices to connect to the network to settle accounts, but digital RMB can be offline. In other words, as long as the mobile phone has electricity, even if the whole network is disconnected, digital RMB can be paid.
PS: Now Alipay and other technologies can actually realize single offline technology, that is to say, in the case that the mobile phone has no network signal, the consumer terminal can actually make consumption, and then postpone the settlement after the consumption is completed. After the network is connected, a short message will inform you that the consumption is successful. But it must be guaranteed that the consumer terminals are networked.
Third, third-party Internet payments such as Alipay and WeChat payment belong to the currency settlement of commercial bank deposits, while digital RMB belongs to cash in circulation. To put it simply, using the central bank digital currency to pay, you consume digital RMB, just like spending cash; Alipay and WeChat payment are just a payment tool. Through these two channels, you can spend the balance in your bank card or swipe your credit card.
3. What is the technical principle for digital RMB to finally realize dual offline payment? What's the tall technology?
This is what I think is the most amazing place. How to realize the security of digital RMB through dual offline technology?
In fact, the function of offline payment is not new. Both WeChat and Alipay have been realized, which allows us to "enjoy first and then pay" in some scenarios. However, this kind of offline payment can only make the payer offline, and the payee must be online and send the offline payment information to the platform server for verification. How is the "offline double payment" of DC/EP realized? According to Alipay who participated in DC/EP, when the cashier and cashier are offline, the account will be reserved first, and then the deduction will be made when the security verification can be done.
However, "double offline payment" also faces higher security risks. Some people may take advantage of the time difference to do evil, such as spending the same kind of digital currency many times. In reality, this is cloned counterfeit money, while the online world only needs to copy the core data of digital currency, which is called "DoubleSpending" in the industry. This is the security issue that we are most worried about.
In order to prevent "double flowers", the third-party payment platform needs to verify every transaction, and "offline payment" cannot be verified in the first time, so it is generally only used in small payment scenarios such as public transportation to reduce risks.
Fourth, the application scenarios and principles of dual offline payment
Dual offline payment core refers to a process of completing business when both the media and the receiving terminal are offline, and the most typical ones are payment business and identity verification. For the payment business, it completes the process of closed-loop transaction by delaying payment after the transaction is completed, and the core is to realize a technical scheme for quickly verifying payment.
Its operating mechanism has two core points. First, the business mechanism has two characteristics, including verification and payment; The other is that there is a trust mechanism between the terminal and the media. The transaction security mechanism has three dimensions: (1) One is the risk control volume, that is, the transaction volume after double offline; (2) Second, there will be a mechanism for advance payment and recovery; (3) The third is the credit system.
5. Is digital RMB touch payment safe? Will someone touch my phone with a mobile phone and steal my money?
The answer is definitely not.
The technology behind the touch payment of digital RMB is actually NFC technology, which is much safer than QR code scanning.
NFC is a short-range high-frequency wireless communication technology. The transmission distance of NFC is less than 10 cm, and it adopts point-to-point communication, without the need for third-party equipment to transmit signals. NFC mobile phones support chip hardware encryption and software encryption, and point-to-point encrypted communication can be completed in less than 0. 1 sec, thus ensuring payment security.
6. Will the mobile phone pay directly when touched?
Of course, you won't pay directly when you touch your mobile phone. After you touch it, you have to enter the payment amount and payment password or fingerprint to complete the transfer. The steps are similar to the current scanning code payment. Undoubtedly more convenient than scanning code payment. Scan code payment cannot be completed under the condition of poor network or poor light. As long as it is within 10 cm, you can pay by touching it. Its payment experience and security are better than scanning code payment.
7. Is there a case similar to dual offline technology?
We know that when both the payer and the payee are offline, we will deduct money from the account first, and then deduct money when we can do security verification.
Think about it, is the bus system like this? There is money in the bus card, and you can swipe your card to get on the bus without internet.
For example, in the case of good network conditions, first recharge the amount to the operator, IC card or mobile phone, and then realize online or offline credit card swiping based on IC technology or NFC technology. If online card swiping is easy to understand, offline card swiping is nothing more than further settlement with the center after networking.