Ethereum split

3. 1. What is the ether classic<

etc (Ethereum Classic) is a bifurcated currency that Ethereum hard bifurcates after 1920000 blocks, and its function is very similar to Ethereum. Etc adheres to the concept of decentralization and supports the consensus mechanism of blockchain guarantee. Etc firmly believes that once the blockchain starts to run, its development direction will not be controlled by any central team, but will be determined by the consensus of the people participating in the whole network and the consensus of the computing power of the whole network

the Ethereum blockchain hard branching in July 2016 aims to transfer the Dao funds stolen by hackers to an account controlled by investors, and let the old transaction records be forgotten by history. Most Ethereum developers are involved in the reversal, as are exchanges, startups and other members of the ecosystem. A few days later, the project returned to normal. But not everyone wants to forget the old record. As a result, a small number of miners continued to use the original blockchain as a protest. They described the hard fork as a capital withdrawal for the abandoned project of the Dao. So Ethereum classic (etc) was born

2. Detailed parameters

Chinese Name: Ethereum classic English Name: Ethereum classic English abbreviation: etc

developer: Ethereum Classic team core algorithm: ethash consensus proof: POW

release date: 2016 / 7 / 20 block time: About 15-17 seconds / block

total currency: fixed at 210 million, up to 230 million, Every 5 million blocks decelerate by 20%, and the first proction rection is expected to be in December 2017

main features: independent cryptocurrency

4. On August 1, 2017, bitcoin cash (BCC), a new blockchain asset based on the original bitcoin chain, was born, which became a hot topic in the streets. The city once exceeded US $7 billion, becoming a digital currency second only to bitcoin and Ethereum
in this process, bitcoin cash also tries its best to ride a roller coaster, which reminds people of Ethereum classic. Comparing bitcoin cash with Ethereum classic, will bitcoin cash become the next bitcoin classic
their similarities are all e to different concepts. A new type of blockchain asset, which is proced by a hard fork, has been separated from the main chain and has gone to an independent development path. They have also experienced price roller coaster fluctuations. They have inherited the mantle of the original chain and changed little. But there are also many differences:
1. Different backgrounds:
in June 2016, the Dao, the world's largest Ethereum project, was stolen from 3.6 million ethereums, with the direct market value as high as US $60 million, which was fatal to the Ethereum community just starting at that time. Vitalik buterin, the founder, and most of the community think that this can't be done. The community decided to roll back the Ethereum transaction through online voting. A small number of people in the Ethereum community think that this violates the irreversible principle of the blockchain and is a violation of the rules. They continue to adhere to the development of the original Ethereum chain, and the Ethereum classic is born and goes to the road of independent development<

bitcoin cash is the proct of the three-year debate over bitcoin expansion. On the one hand, some community members and developers who insist on large blocks are tired of endless debates. Although the New York consensus on community consensus scheme has won a phased victory, the future is still uncertain, and supporters of large blocks hope to move towards an independent development path; On the other hand, the community support rate of large blocks is also very high. Although the Bu expansion scheme often appears bugs, it still gets 40% of the computing power support of the whole network. Bitcoin cash is born out of the Bu expansion scheme, which continues the original intention of Nakamoto's design of bitcoin and makes certain changes in technology. It is a new technology attempt. In this context, bitcoin cash came into being to adapt to the development trend of the times
2. Different attention and influence
the predecessor of bitcoin cash is bitcoin, the Ruan Sheng brothers of bitcoin, and bitcoin is the global digital currency hegemony. After the separation of bitcoin from cash and main chain, bitcoin and bitcoin have taken different development paths. Bitcoin cash can be said to be born with the golden key. As soon as it comes out, it has won extensive attention from the community and become the focus of community discussion. News is flying all over the world, and many mainstream trading platforms at home and abroad also choose to support it. After a short period of adjustment, the price graally returned to rationality. The municipal government once ranked in the top three and still ranks in the fourth
Ethereum is the predecessor of Ethereum classic. Ethereum only ranked second in the global digital currency this year. In 2016, its popularity and community influence were not too high. The Ethereum classic split out is not optimistic by the community. There are few online platforms, and the price is plummeting all the way. The attention and influence of Ethereum classic in the community has not been high. The Municipal People's government has been unable to enter the top ten. There are no opportunities for community discussion and media attention. After several rounds of outbreak, the Municipal People's government has only ranked ninth
to sum up, bitcoin cash and Ethereum classics are different in terms of attention, community influence and historical background. The future development of bitcoin cash will be better. If the bitcoin community is still in constant infighting, does not want to make progress and refuses to change, bitcoin cash will have a chance to shake the dominant position of bitcoin, Instead.

5. Ethereum fog, or ETF for short, is a branch chain of Ethereum, which is designed to solve the problem of distributed storage and distributed computing power that Ethereum lacks. In the later stage, it will switch to the hybrid mining of pow + POS. The original coin is ETF

after Ethereum bifurcates into etheric fog, the two will exist and develop together< br />

6. Due to Ethereum's decentralization, vitalik buterin's decision to roll back transactions must be approved by at least 51% of users. As a result, Ethereum is divided into two groups. One group is Ethereum classic. They insist on the original intention that the blockchain cannot be changed and stay to maintain the original Ethereum. The other is etherum, maintained by the vitalik buterin team. This is the origin of Ethereum classic brought by "Ethereum hard fork". Contributor: bitewang

7. 650mah is battery capacity
bak means that the cell is proced by bicker company<
423048 refers to the specification of the cell (internal part of the battery), which is 4.2mm in thickness * 30MM in width * 48mm in length (please check it yourself)
btc8g26 / 04kh is the traceability code of the battery. If you find that there is a problem with the battery, especially the safety problem, return it to the manufacturer, and the manufacturer can find out the proction material, proction process, proction shift date and other information of the battery according to this code, so as to find out the cause of the battery problem, and improve the proction material and process, so as to avoid similar problems with other batteries. If necessary, call back the problem batteries of the same batch, Avoid greater losses, especially when there are fatal problems such as fire
I am a proction engineer of lithium battery. If you have any questions, please leave a message on my blog
ha ha, is the answer professional enough?

8. Bitcoin cash (BCH) is a branch of bitcoin. In fact, in addition to bitcoin cash, bitcoin also has many bifurcated currencies. What does bifurcated currency mean
section one: why do you split up when you don't say a word
the concept of bifurcation originated from bitcoin
as we know, bitcoin trading is based on bitcoin blockchain network (one block by one forms a chain of front and back Association, forming a bitcoin blockchain network). Since a block is a block, it must have capacity (let's fill in the block, it is nothing more than a collection of codes), The size of the block capacity will limit the efficiency of the transaction. If the block capacity is too small, the smaller the number of transactions will be. Once the transaction volume is too large, it will cause congestion
the capacity of bitcoin block is only 1m, and it can hold only 5-7 transactions. In the past, there were relatively few users for bitcoin transactions, so this capacity is no problem. However, with the rise of bitcoin price, more and more users swarmed in, and the bitcoin block could not accommodate so many transactions, resulting in congestion
bitcoin is anxious: slow down, brother Dei, I can't keep up with your trading speed. Hello! Users are also anxious: brother, can you hurry up
this is a big problem, not only because we have limited patience, but also because bitcoin's positioning is currency. As a currency, you should pay and collect money quickly, accurately and ruthlessly. If you are always so slow, when can you realize the currency attribute? So, this is a big problem
of course, the bitcoin community knows the importance of this problem. As for how to solve this problem, the bitcoin community is divided on whether to expand the capacity of bitcoin blocks (as we have just said, it is too little capacity of bitcoin blocks that leads to slow transaction speed and congestion)
the controversy is mainly divided into two camps:
the original development team of bitcoin, led by core, believes that bitcoin is an electronic gold of value storage, which will destroy its core once it is expanded
however, the mining team led by Wu Jihan believes that bitcoin should be a kind of currency with rapid circulation in the future, and it needs to be expanded to solve the problem of transaction congestion. Because of the decentralized nature of the blockchain, no indivial or organization can decide how to "expand" the bitcoin system. Everyone has their own opinions, and their opinions are divided. No one is willing to give in. Therefore, everyone goes their own way. The bitcoin chain has split into BTC and BCH chains, and over time it has evolved into the so-called "bifurcation"
this is the origin of bifurcation
what happens after the second section bifurcates
for blockchain, bifurcation is the change of blockchain protocol, which is similar to upgrading the blockchain to make up for the shortcomings of the system. This is just like our current mobile phone software often prompts you to upgrade
however, we know that blockchain is decentralized. Unlike your mobile software, developers can upgrade when they say so. In the world of blockchain, any modification needs the consensus of all members. No one can decide when to change or how to change the underlying agreement of blockchain
therefore, when the original development team of bitcoin and the miner team have differences, the system will be divided into two parts, and two new systems based on the original blockchain will appear. Everyone has their own problems, and no one can intervene. In this way, the bitcoin system is divided into two chains: BTC and BCH, which are called "bifurcations", and BCH is called bifurcated currency (the bifurcated currency of bitcoin)
in fact, not only BCH, but also bitcoin has many bifurcated coins. Why is BCH the first thing to think of when it comes to bifurcated currencies? This is because BCH is a successful bifurcated currency. When its market value is the highest, it ranks the fourth in the list of cryptocurrencies, next only to bitcoin, Ethereum and EOS
section 3 hard fork and soft fork
let's make a metaphor: if bitcoin system is the trunk of a big tree, then BCH and other fork coins are the branches of the tree. However, bifurcation is not as simple as this metaphor. It can be divided into hard bifurcation and soft bifurcation
first, hard bifurcation: goodbye, never see again
the BCH we mentioned above belongs to hard bifurcation. Hard bifurcation means that nodes using old software can no longer verify blocks proced with new software nodes. If you want to verify, you can only upgrade. After upgrading, it is equivalent to changing the track and running on another new system. Just like BCH to BTC, BCH is a brand new track (a brand new chain), and the coin on this chain is BCH (bitcoin cash). Then, nodes using BCH system can no longer go to BTC network for transaction verification. Hard bifurcations, generally speaking, mean going their own way. There is no intersection any more< Second, soft bifurcation: getting better to meet again
soft bifurcation is opposite to hard bifurcation. Soft bifurcation means that nodes using the old version can verify the blocks proced by nodes using the new version, and nodes using the new version can also verify the blocks proced by nodes using the old version. The two versions are compatible
the way bitcoin upgraded its isolation witness in 2017 is soft bifurcation. In the whole process, it doesn't matter whether we use the old version or the new version, because they are compatible. The new version only solves some problems better. In essence, we are still running on the bitcoin chain, and there is no new coin
to sum up, the difference between soft fork and hard fork is whether nodes using old software can be compatible with nodes using new software. Compatibility is soft fork, while incompatibility is hard fork.

9. Overview of power over Ethernet (POE)

POE (power over Ethernet) refers to the technology that can provide DC power supply for some IP based terminals (such as IP telephone, WLAN access point AP, network camera, etc.) while transmitting data signals without any changes to the existing Ethernet cat. 5 wiring infrastructure. Poe technology can ensure the security of the existing structured cabling, ensure the normal operation of the existing network, and minimize the cost

Poe is also known as power over LAN (POL) or active Ethernet (active Ethernet), sometimes referred to as Ethernet power supply, which is the latest standard specification of using existing standard Ethernet transmission cable to transmit data and power at the same time, and maintains the compatibility with existing Ethernet system and users. IEEE 802.3af standard is a new standard based on POE of power supply system over Ethernet. It adds the relevant standard of direct power supply through network cable on the basis of IEEE 802.3. It is an extension of the existing Ethernet standard and the first international standard on power distribution<

IEEE began to develop this standard in 1999. The earliest participating manufacturers were 3Com, Intel, powerdsine, Nortel, mitel and national semiconctor. However, the shortcomings of the standard have been restricting the expansion of the market. Until June 2003, IEEE approved 802.3af standard, which clearly stipulated the power detection and control matters in remote system, and regulated the power supply mode of router, switch and hub to IP phone, security system and wireless LAN access point through Ethernet cable. The development of IEEE 802.3af includes the efforts of many company experts, which also makes the standard can be tested in all aspects

a typical Ethernet power supply system is shown in Figure 1. The Ethernet switch equipment is reserved in the distribution cabinet, and a midspan hub is used to supply power to the twisted pair of LAN. At the end of the twisted pair, the power supply is used to drive phones, wireless access points, cameras and other devices. To avoid power failure, a UPS can be selected<

Figure 1 a typical Ethernet power supply system

key technology of Poe

system composition and power supply characteristic parameters of Poe
a complete Poe system includes two parts: power souring equipment (PSE) and power device (PD). PSE equipment is the power supply equipment for Ethernet client equipment, and it is also the manager of the whole Poe Ethernet power supply process. PD device is the client device of Poe system, such as IP phone, network security camera, AP, PDA or mobile phone charger and many other Ethernet devices (in fact, any device with power less than 13W can get the corresponding power from RJ45 socket). Based on IEEE 802.3af standard, they establish information contact about PD connection, device type, power consumption level and so on, and supply power to PD through Ethernet according to PSE
the main power supply characteristic parameters of Poe standard power supply system are:
the voltage is between 44 and 57V, and the typical value is 48V
the maximum allowable current is 550mA and the maximum starting current is 500mA
the typical working current is 10 ~ 350mA, and the overload detection current is 350 ~ 500mA
under no-load condition, the maximum required current is 5mA
provide PD equipment with 5 levels of power request (3.84-12.95w), with the maximum power not exceeding 13W
working process of Poe power supply
when the PSE power supply terminal equipment is arranged in a network, the working process of Poe Ethernet power supply is as follows
detection: at the beginning, the PSE device outputs a small voltage at the port until it detects that the cable terminal is connected to a receiving end device supporting IEEE 802.3af standard
PD end equipment classification: when PD is detected at the receiving end, the PSE equipment may classify the PD equipment and evaluate the power loss required by the PD equipment
start power supply: in a configurable time (generally less than 15 minutes) μ s) During the start-up period, PSE equipment began to supply power to PD equipment from low voltage to 48V DC power supply
power supply: provide stable and reliable 48V DC power for PD equipment to meet the power consumption of PD equipment within 15.4W
power off: if the PD device is disconnected from the network, the PSE will quickly (generally within 300-400ms) stop supplying power to the PD device, and repeat the detection process to detect whether the cable terminal is connected to the PD device
when connecting any network device to the PSE, the PSE must first detect whether the device is a PD to ensure that it does not supply current to Ethernet devices that do not meet the POE standard, because this may cause damage. This kind of check is realized by providing a small current limited voltage to the cable to check whether the far end has the required characteristic resistance. Only when the resistance is detected, the full 48V voltage will be provided, but the current is still limited to avoid the terminal equipment in the wrong state. As an extension of the discovery process, PD can also classify the power supply modes that require PSE, which helps PSE to provide power in an efficient way. Once the PSE starts to provide power, it will continuously monitor the PD current input. When the PD current consumption falls below the minimum value, such as when the device is unplugged or when the power consumption of the PD device is overloaded, short circuited or exceeds the power supply load of the PSE, the PSE will disconnect the power supply and start the detection process again
power supply devices can also be provided with a system management capability, such as the application of simple network management protocol (SNMP). This function can provide functions such as night shutdown and remote restart
by studying the power supply mode of Poe, we can see that there are two key issues to be considered in the process of power supply, one is the identification of PD equipment, the other is the capacity of ups in the system
the principle of Poe power supply through cable
there are four pairs of twisted pair in the standard five kinds of network cable, but only two pairs of them are used in l0m Base-T and 100m base-t. IEEE80 2.3af allows two uses, as shown in Figure 2 and figure 3

Figure 2 supplies power through the free pin
Figure 3 supplies power through the data pin

when applying the free pin power supply, the 4 and 5 pins are connected to the positive pole, and the 7 and 8 pins are connected to the negative pole
when the data pin is used for power supply, the DC power supply is added to the midpoint of the transmission transformer, which does not affect the data transmission. In this way, pair 1, 2 and pair 3, 6 can be of any polarity
the standard does not allow the above two cases to be applied at the same time. Power supply equipment PSE can only provide one usage, but power application equipment PD must be able to adapt to both situations. The standard stipulates that the power supply is usually 48V, 13W. It is easy for PD equipment to provide 48V to low voltage conversion, but at the same time, it should have 1500V insulation safety voltage
the POE standard also specifies the unshielded twisted pair cables used to transmit electric power, i.e. Category 3, 5, 5e or 6 cables. It is clear that the existing cable facilities working with them do not need any changes, including category 3, 5, 5e or 6 cables, various short wiring and terminal blocks, power socket leads and connecting hardware, etc. Poe standard is compatible with IEEE 802.3 standard series
two power supply methods of Poe
Poe standard defines two methods for using Ethernet transmission cable to transmit DC power to Poe compatible devices: one is called mid span method, which uses unused free pairs in Ethernet cable to transmit DC power, and the corresponding endpoint PSE supports Ethernet switch, router, router with POE function A hub or other network switching device. Another method is "end span", which is to transmit DC power on the data transmission core at the same time, and the transmission frequency is different from that of Ethernet data signal. The midspan PSE is a dedicated power management device, usually placed with a switch. It has two RJ45 jacks corresponding to each port, one is connected to the switch with a short line, and the other is connected to the remote device. It can be predicted that end span will be popularized rapidly. This is e to the fact that Ethernet data and power transmission adopt common line pair, thus the need to set up independent power transmission special line is eliminated. This is of great significance for the cable with only 8 cores and the matching standard RJ-45 socket
Figure 4 is an example of Poe power supply system, which is composed of power supply equipment PSE, power receiving equipment PD, relevant supporting equipment and Ethernet transmission cable

Fig. 4 example of Ethernet power supply system conforming to IEEE 802.3af Standard

when PD equipment is compatible with POE standard, it can directly supply power from Ethernet cable through RJ-45 socket. For equipment not compatible with POE, DC converter or tap voltage divider can be used to convert its voltage into Poe compatible voltage. These devices, sometimes called active Ethernet splitters, can take the DC voltage from the Ethernet cable and supply it to PD devices through conventional DC sockets
the advantages of Poe technology and expanded application

the advantages of using Ethernet power supply are obvious:

Poe only needs to install and support one cable, which is simple and space-saving, and the equipment can be moved at will
cost saving. Many live equipment, such as video surveillance cameras, need to be installed in places where it is difficult to deploy AC power. Poe makes it no longer need expensive power supply and time-consuming to install power supply, saving cost and time
like data transmission, Poe can monitor and control the device by using simple network management protocol (SNMP)
Poe power supply terminal equipment will only supply power to the equipment that needs power supply. Only when the equipment that needs power supply is connected, the Ethernet cable will have voltage, thus eliminating the risk of leakage on the line
a single UPS can provide power supply for all related equipment in case of power failure
users can automatically and safely mix existing devices and Poe devices on the network, and these devices can coexist with existing Ethernet cables
make network devices easy to manage. Because when the remote device is connected to the network, it can be remotely controlled, reconfigured or reset
in WLAN, Poe can simplify RF test tasks, and access points can be easily moved and accessed
with the establishment of IEEE 802.3af standard, a large number of other applications will emerge rapidly, including bluetooth access point, lighting work, network printer, IP phone, web camera, wireless bridge, building security system, such as access card reader and monitoring system, etc. Users can provide 48V DC power supply on the existing network cable by fusing new power supply devices on the current Ethernet equipment, which reces the total cost of network construction and protects the investment. Some manufacturers have launched procts on the market, such as the midspan hub with power supply

the core of Poe is to transmit 48V rated voltage to PD array through Ethernet cable. IP phone is a kind of receiving equipment. Other devices include Wi Fi device, bluetooth access point, network camera and retail terminal

pots (traditional telephone service) transmits the rated voltage of 48V to the user's phone through the local switch, and this transmission will be carried out as we pick up the phone. But for many specific Poe applications such as VoIP, the key is to know whether NCPI can support these PDS and whether they can be used

10. The best answer is
1) abscisic acid can inhibit the synthesis of RNA and protein, thus inhibiting the growth of stem and lateral bud; Ethylene can promote the synthesis of RNA and protein, increase the permeability of cell membrane, accelerate respiration and accelerate maturation. This is antagonism
abscisic acid inhibits cell division and promotes leaf and fruit senescence and abscission. Ethylene promotes fruit ripening, Organ Abscission and senescence. This is synergy.