What does blockchain mobile mean
The strict definition of blockchain refers to the distributed database technology that multiple nodes in peer-to-peer network jointly maintain a continuously growing list ledger constructed by time stamp and orderly record data blocks through consensus mechanism based on cryptography technology. This technical solution allows any number of nodes in the participating system to calculate and record all the information exchange data in the system in a period of time to a data block through cryptography algorithm, and generate the fingerprint of the data block for linking the next data block and checking. All participating nodes in the system jointly determine whether the record is true
blockchain is a technical solution similar to NoSQL (non relational database). It is not a specific technology, and can be implemented through many programming languages and architectures. There are many ways to realize blockchain, including pow (proof of work), POS (proof of stake), dpos (delegate proof of stake), etc
the concept of blockchain was first proposed in the paper "bitcoin: a peer-to-peer electronic cash system" by indivials (or groups) who call themselves Satoshi Nakamoto. Therefore, bitcoin can be regarded as the first application of blockchain in the field of financial payment
< H2 > [popular explanation]no matter how big the system or how small the website is, there is a database behind it. So who will maintain this database? In general, who is responsible for the operation of the network or system, then who is responsible for the maintenance. If it is wechat database, it must be maintained by Tencent team, and Taobao database is maintained by Alibaba team. We must think that this way is natural, but blockchain technology is not
if we think of the database as a book, for example, Alipay is a typical account book. Any change of data is bookkeeping. We can think of database maintenance as a very simple way of accounting. In the world of blockchain, everyone in the blockchain system has the opportunity to participate in bookkeeping. The system will select the fastest and best bookkeeper in a period of time, maybe within ten seconds or ten minutes. The bookkeeper will record the changes of the database and the account book in a block. We can think of this block as a page. After the system confirms that the records are correct, the system will record the changes of the database and the account book in a block, It will link the fingerprint of the past account book to this paper, and then send this paper to everyone else in the whole system. Then, over and over again, the system will look for the next person with fast and good bookkeeping, and everyone else in the system will get a of the whole ledger. This means that everyone as like as two peas in the system is called Blockchain. It is also called distributed account technology. P>
as like as two peas (computer) have identical accounting books, and everyone has the same rights, they will not collapse e to the loss of contact or downtime of a single person. As like as two peas, the data is transparent and everyone can see what changes are in every account. Its very interesting feature is that the data can't be tampered with. Because the system will automatically compare, it will think that the same number of books with the largest number are real books, and a small number of books with different numbers are false books. In this case, it's meaningless for anyone to tamper with his own account book, because unless you can tamper with most nodes in the whole system. If there are only five or ten nodes in the whole system, it may be easy to do so. However, if there are tens of thousands or even hundreds of thousands of nodes and they are distributed in any corner of the Internet, unless someone can control most computers in the world, it is unlikely to tamper with such a large block chain
< H2 > [elements]combined with the definition of blockchain, we think that we must have the following four elements to be called public blockchain technology. If we only have the first three elements, we will consider it as private blockchain Technology (private chain)
1, peer-to-peer network (power equivalence, physical point-to-point connection)
2, verifiable data structure (verifiable PKC system, non tampering database)
3, distributed consensus mechanism (Solving Byzantine general problem, solving double payment)
4 Game design of Nash equilibrium (cooperation is the strategy of evolutionary stability)
combined with the definition of blockchain, blockchain will realize four main characteristics: decentralized, trustless, collective maintenance and reliable database. And the other two will be derived from the four characteristics Features: open source Privacy. If a system does not have these characteristics, it can not be regarded as an application based on blockchain technology
Decentralized: there is no centralized hardware or management organization in the whole network. The rights and obligations of any node are equal, and the damage or loss of any node will not affect the operation of the whole system. Therefore, it can also be considered that the blockchain system has excellent robustnesstrustworthiness: there is no need to trust each other when participating in the data exchange between each node in the whole system. The operation rules of the whole system are open and transparent, and all data contents are also open. Therefore, within the specified rule range and time range of the system, nodes cannot and cannot cheat other nodes
collective maintenance: the data blocks in the system are maintained by all the nodes with maintenance function in the whole system, and these nodes with maintenance function can be participated by anyone
reliable database: the whole system will enable each participating node to obtain a of the complete database in the form of sub databases. Unless more than 51% of the nodes in the whole system can be controlled at the same time, the modification of the database on a single node is invalid, and the data content on other nodes cannot be affected. Therefore, the more nodes and computing power in the system, the higher the data security in the system
Open Source: since the operation rules of the whole system must be open and transparent, the whole system must be open source for the program
Privacy Protection: since there is no need to trust each other between nodes, there is no need to disclose the identity between nodes, and the privacy of each participating node in the system is protected
Blockchain is a shared database. Blockchain is a new application mode of computer technology, such as distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and so on
main features:
1. Decentralization. Blockchain technology does not rely on additional third-party management institutions or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes information self verification, transmission and management through distributed accounting and storage
2. Openness. The foundation of blockchain technology is open source. In addition to the private information of all parties to the transaction is encrypted, the data of blockchain is open to everyone. Anyone can query blockchain data and develop related applications through the open interface
3. Independence. Based on consensus specifications and protocols, the whole blockchain system does not rely on other third parties, and all nodes can automatically and safely verify and exchange data in the system without any human intervention
4. Safety. As long as 51% of all data nodes cannot be controlled, the network data cannot be arbitrarily manipulated and modified, which makes the blockchain itself relatively safe and avoids subjective and artificial data changes
5. Anonymity. Unless there are legal requirements, technically speaking, the identity information of each block node does not need to be disclosed or verified, and the information can be transferred anonymously
extended data
application direction:
1. Payment: for example, in terms of time, traditional cross-border remittance takes 10 minutes or several days, while blockchain cross-border remittance can achieve remittance in seconds e to decentralization. In terms of convenience, traditional cross-border remittance needs to wait until the next day after 19:00, while blockchain cross-border remittance only needs one mobile phone to realize all-weather remittance
2. Sharing medical records: the medical data blockchain sharing platform can achieve many application scenarios. Patient history data and other information can be linked, and medical history and image data can be viewed by personnel entering the system. These medical data can also be used for modeling and machine learning
source: network blockchain
HTC is developing an Android mobile phone driven by blockchain technology. The phone, codenamed exos, will provide a system level wallet function with built-in security hardware to support digital cryptocurrency and decentralized applications
at present, HTC's proct focus is virtual reality helmet vive. Phil Chen will be responsible for all blockchain and cryptocurrency related projects within HTC, including the exos phone
However, e to the lack of a real phone, it is not clear what kind of functions this kind of blockchain mobile phone can provide that are different from conventional mobile phones, so as to improve the transaction experience of digital cryptocurrencyit is said that the blockchain mobile phone will improve the security and user experience ring transaction by integrating the native wallet function in the mobile phone. It can also conct direct digital cryptocurrency transactions among users in the network composed of the mobile phone, eliminating the cost of mining
however, the above mentioned functions can be realized on ordinary smart phones by installing software. The transaction of bitcoin and other digital cryptocurrencies will generate mining costs, which can not be avoided on ordinary mobile phones or blockchain mobile phones. Web browsers and chat applications that provide privacy protection can also be implemented by installing applications
The great Magellanic nebula is about 180000 light-years away, the Magellanic nebula is 210000 light-years away, and the bright star on the lower left is the base of the ship α Old man star, a resident of the galaxy, is only 310 light-years away. Both big and small clouds are in the southern half of the sky, and the sphere is about 20 meters away from the southern pole ° Right and left. Located at the junction of the two constellations, Xiphophorus and Yamagata, the cloud spans the two constellations and occupies 8 °× seven ° The area of the sky is equivalent to the apparent area of more than 200 full moons. The wheat cloud is located in Rhododendron, occupying 4 °× two ° It's the area of 30 full moons. The distance between the barley cloud and the wheat cloud is about 20 meters ° In the southern hemisphere, the big and small wheat clouds hang high near the zenith of the southern sky all the year round. They never fall below the horizon. As we see in the northern hemisphere, the Big Dipper will never fall below the horizon. They are a pair of treasures of Nantian. Unfortunately, most of the northern hemisphere can't see them. In the Spratly Islands area of China, they are only found near the southern horizon.
the Magellanic nebula is a small and irregular galaxy. It is a satellite galaxy of the Milky way and orbits around the Milky way once every 1.5 billion years. Because it has no standard fixed shape, the Magellan Nebula has become the most controversial object in the southern hemisphere, even the most imaginative object. Some astronomers say that the Magellanic Nebula seems to interact with dark matter in the universe to form a galaxy bend
what is galactic curvature? I think this is more difficult to explain. To put it simply, the operation of nearby nebulae may have an impact on our galaxy, just like the agitation of the other end of the carpet, which can cause a wave like shape distortion. At present, the Galactic silver plate has become a bowl
apart from the rosy Keyhole Nebula and the shining Southern Cross, the most famous celestial bodies in the southern hemisphere belong to the large and Small Magellanic galaxies. The Milky way is not visible in the Chinese mainland. These two celestial bodies are the galaxy of the galaxy. Like M32, NGC205, next to the M31, is a small galaxy near the big galaxy. LMC is 160000 light-years away from the earth, and SMC is 190000 light-years away from the earth
when German Amateur Astronomer Tonghao came to Australia to observe stars, he mistook LMC and SMC for two "clouds" in the sky. How can the wind not blow away? It was a joke. Ngc104 next to SMC is another good object to watch, and the spider Nebula next to LMC should not be missed
like our Milky way, Magellanic Clouds also include gas and stars. Barley cloud belongs to the dwarf spiral galaxy or irregular galaxy, and its mass is 1 / 20 of that of the Milky way. Wheat cloud is an irregular galaxy or an irregular rod dwarf galaxy with only 1 / 100 of the mass of the Milky way. There are abundant gases in magellanic clouds; The mass of neutral hydrogen is 9% and 32% of their total mass respectively, which is much larger than that of the Milky way. This suggests that they are less evolved than the Milky way. Their interstellar st content is less than that in the Milky way, while the young group I has a large number of objects, with a large number of high luminosity O-B stars; In addition, new stars, supernova remnants and X-ray binaries have been observed. For example, a supernova (SN 1987A) in the Large Magellanic Cloud was discovered on February 23, 1987. Its maximum brightness is 250 million times that of the sun. It is considered to be the brightest supernova in 383 years. Magellanic Clouds orbit the Milky way once every 1.5 billion years. Every time it gets closer to the Milky way, its stars and gases will change under the gravity of the Milky way. The Magellanic Cloud has now been torn apart and its stars will become part of the Milky way. The big magellanic cloud will eventually be the same fate
the large and Small Magellanic nebulae are the closest neighbors to the Milky Way galaxy. For hundreds of years, these two nebulae have been considered as companion galaxies of the Milky way. But a new study by Harvard astrophysicist gurtina besla and his colleagues shows that the Magellanic Cloud is a recent arrival and the first visitor to the galaxy
the two nebulae are not only irregular in appearance, but also like volcanic clouds. The Large Magellanic nebula is 160000 light-years away from the earth, and its diameter is about 1 / 20 of that of the Milky way; The Magellanic nebula is 200000 light-years away from earth and is only a few hundredths the size of the Milky way
many years ago, astronauts claimed that the three-dimensional velocity field of the Magellanic Nebula passing through the Milky way is much larger than before. There are two explanations for this phenomenon: 1) the Milky way is much larger than before; 2) the Magellanic nebula is not constrained by the gravity field of the Milky way. But further research by besla and his colleagues confirms the second view, and they claim that the Magellanic Nebula passed through the Milky way for the first time
however, such observations are still questionable. Because if we take the Milky way as the reference plane, the warping depth can reach 10000 light-years up and down. But these two nebulae only arrived once a billion or three billion years ago, so their gravity tides are unlikely to cause such warping. Faced with such a situation, besla said: "we still have a lot of unsolved mysteries. When an answer appears, there may be more problems."
In the 10th century, when Arabs and Portuguese sailed to the south of the equator in the 15th century, they noticed these two cloud like objects in the southern sky, which were called "Cape of good hope clouds". Portuguese navigator Magellan first described them accurately when he sailed around the world in 1521, and later named them after him. The big cloud is called the big Magellanic nebula, or LMC for short; The small cloud is called wheat cloud (SMC); Collectively known as Magellanic Cloud. In 1912, American astronomer Leavitt discovered the relationship between the circumference of the Cepheid variable of the wheat cloud. Herzpolon and Shapley then determined the distance of the wheat cloud, becoming the first confirmed extragalactic galaxy. The distance of big wheat cloud is 160000 light years, and that of wheat cloud is 190000 light years. They are 50000 light years apart in space. Large and small clouds are among the most recent galaxies, which enables us to analyze their member celestial bodies carefully. Therefore, they are important astronomical observation objects and important sources of galactic astrophysical data
recently, triangle mobile phone, a necessary artifact for blockchain users, officially appeared on its official website. The mobile phone puts forward the innovative idea of using blockchain thinking as a mobile phone: each mobile phone is a node, and each node will own more than 51% of the rights and interests generated by the behavior data contributed by the network, That is to let every user become the creator and sharer of the brand.