Is there only one blockchain

1. At present, there are three application deployment types of blockchain: public chain, private chain and alliance chain. What's the difference between them? What are the typical applications<

public chain: open to all, anyone can participate

private chain: open to indivial indivials or entities

alliance chain: open to specific organizations

2. bitcoin blockchain is a bitcoin blockchain? No, the block stores the transaction. In the early stage, you will get a coin if you successfully build a block. In the later stage, you can only get the fees paid by the exchange. A currency is a string of digital signatures. It is a digital signature sent by the last owner to the receiver. Everyone can see who owns the currency from the transaction
does each node have complete blockchain data? You mean a user node? A user node needs to keep the of the block head of the longest workload proof chain, so it knows the data of all the block heads. It can move forward to know all the data on the block chain, but not all of them are saved. A block header is very small, only 80 bytes, which can be saved completely, because the generation of nodes is very slow. Even with the passage of time, the amount is not too large now.

3. Jinwowo analysis: a node is actually a computer (server) connected to the blockchain. Any connected computer can access the blockchain, so there are countless nodes on the blockchain; However, the number of blocks on the blockchain is limited, that is, one block is generated every 10 minutes, and no new blocks will be added after reaching a certain number.

4. Method 1: enter DFU mode when power on
connect the device to the computer with USB cable, and then you will hear the prompt sound that the computer has been connected successfully
please turn off the device first, and then you will hear the prompt that the computer is not connected successfully
first press and hold the power key to display the apple logo, and then press and hold the on / off key and the home key until the logo disappears. Continue to press and hold the power key for about 4-5 seconds, and continue to press and hold the home key until an iPhone in recovery mode is detected by iTunes (if successful, the iPhone should be in black screen). If redsn0w is used to detect, the device model in DFU will be displayed at the bottom of the interface< Method 2: enter DFU in any state (white apple or unlimited restart)
connect the device to the computer
Press and hold the on / off key and home key directly until the logo disappears. Just follow the above steps
method 3: do not press the key to enter the DFU (it is recommended to use the device with damaged key)
download the firmware of the device corresponding to the latest system version (do not use the firmware that Apple has closed for verification)
Download redsn0w and enter extra even more DFU IPSW in turn
at this time, redsn0w will prompt you that this is the operation of making DFU firmware, not the normal operation of restoring the system. The choice is
after selecting the latest official firmware, redsn0w will start making DFU firmware and wait for completion
Open iTunes, close redsn0w, shift + restore (for Mac, please use option + restore) and select the DFU firmware (prefixed with enter)_ DFU), wait for error 37 in the recovery process. At this time, the device is already in DFU mode.

5. Jinwowo network technology believes that: blockchain technology is not just a single technology, but a collection of multiple technology research. Blockchain has several core technologies: distributed data storage, cryptography principle, and consensus mechanism
in the future, jinwowo will continue to tap the value of blockchain technology in the commercial field

6. Unknown_Error