Principle of P2P protocol and blockchain

2. P2P means peer-to-peer, and P2P network is a peer-to-peer network scene, characterized by decentralization. Blockchain is a technical means for the development of P2P network. It can be simply understood that a block is an account book that records all the information generated by the whole network in a certain period of time. In the P2P network, the data exchange and synchronization between each node need huge computing power, and the block technology is born to solve this problem.

3. bitcoin P2P technology is a virtual encrypted digital currency. That's right. It's more essential. The term blockchain came into being after the birth of bitcoin, because bitcoin opened the door to the blockchain field. The popularity of bitcoin has attracted more and more people's attention to blockchain technology. Before the birth of blockchain, many veteran people used to call it P2P, which is probably the case. Many of the world's leading exchanges, such as okex, have developed some functions based on blockchain technology. You can learn more about okex platform.

4. This has not been studied, but the application prospect of blockchain to P2P:
bitcoin (digital currency) and P2P are two major branches of Internet finance. Bitcoin has applied blockchain technology, so can P2P< As a part of the blockchain, regulatory authorities (central bank, China Banking Regulatory Commission and China Securities Regulatory Commission) can obtain the public accounts of P2P transactions in real time, and obtain the financial management projects and capital transfer information of each P2P enterprise by analyzing the public accounts, so as to provide low-cost, efficient and reliable regulatory data for P2P instry supervision in real time
Second, the borrower's credit information is transparent
the main solution of blockchain is the credit problem, so blockchain is most promising to be applied to credit information. However, there are many controversies about credit information. After all, the data related to credit information is very sensitive. Both credit information institutions and users do not want to make it public. Data is the lifeblood of credit information institutions. Every family wants others to make it public and keep it secret. Users also don't want their data to be public. Of course, if we can achieve the transparency of credit investigation in the future, it will be very beneficial for P2P investors
thirdly, the transaction structure should be low-cost.
for a P2P platform, the monthly withdrawal fee of users is also a big expense, but the general P2P platform will pay this part of the fee out of its own pocket. It is a good thing for the P2P platform to apply the powerful online transaction function of blockchain, go to the third party payment, or bank fund custody, and complete the fast, prepared and transparent transaction of funds< Fourth, instry infrastructure
the rapid development of most things is largely e to the improvement of infrastructure. At present, blockchain technology can be used as a very important new infrastructure construction of P2P and even the whole Internet financial system, similar to the great changes of highway to automobile transportation instry and container to ocean transportation instry For example, blockchain content publishing platform is also a P2P content publishing platform.

5. The concept of P2P

P2P is the abbreviation of peer-to-peer. In English, peer has the meanings of "peer", "colleague" and "partner". In this way, P2P can be understood as "partner to partner", or peer-to-peer networking. At present, people think that it has a bright future in enhancing people's communication, file exchange, distributed computing and so on

in short, P2P directly connects people and enables people to interact directly through the Internet. P2P makes communication on the network easier, more direct sharing and interaction, and truly eliminates middlemen. P2P means that people can directly connect to other users' computers and exchange files, instead of connecting to the server to browse and download as in the past. Another important feature of P2P is to change the Internet's current big website centered state, return to "decentralization", and return power to users. P2P seems to be very new, but just as B2C and B2B transplant common things in the real world to the Internet, P2P is not new. In real life, we communicate face to face or by telephone according to P2P mode every day

even from the perspective of network, P2P is not a new concept. P2P is the foundation of the overall Internet architecture. TCP / IP, the most basic protocol of Internet, has no concept of client and server. All devices are the equal end of communication. Ten years ago, all systems on the Internet had both server and client functions. Of course, the later developed software based on TCP / IP does adopt the client / Server Structure: browser and web server, mail client and mail server. However, for servers, they are still peer-to-peer networking. Take e-mail as an example, there is not a huge and unique e-mail server on the Internet to handle all e-mails, but peer-to-peer e-mail servers cooperate with each other to send e-mails to the corresponding servers. In addition, email between users is always a peer-to-peer communication channel. Of course, but in the past five years, the development of the Internet has at least distanced itself from P2P on the surface, and most of the nodes on the Internet can not communicate directly with other nodes. Napster awakens the peer-to-peer networking that is deeply behind the Internet. Napster's file sharing function is a common thing to share directory in LAN. But Napster's success has made people realize the possibility of extending this "peer-to-peer networking" to the whole Internet. Of course, in the eyes of many people, Napster is not pure P2P, it still needs a central coordination mechanism

in fact, many existing services on the network can be classified as P2P. Instant messaging systems such as ICQ, AOL Instant Messenger, Yahoo pager, MSN Messenger from Microsoft and OICQ in China are the most popular P2P applications. They allow users to communicate and exchange information and files with each other. The information exchange between users is not direct, it needs a server in the center to coordinate. However, these systems do not have such functions as search, which are very important for a large number of information sharing. The lack of this feature may be one of the reasons why instant messaging has appeared for a long time, but it has not been able to proce such an impact as Napster

another thing that can be classified as P2P is auction websites, such as eBay. When people summarize the mode of eBay, they use C2C. Is it a bit similar to P2P? EBay is a community that connects people and trades goods. Users can easily search for goods that other users sell. EBay offers some services to make the transaction go smoothly, but the transaction is directly between users. If the concept of "transaction" is extended, C2C is a special case of P2P, where people exchange goods with each other

but if we look into it carefully, Napster and instant messaging give users the ability to communicate directly and eBay allows users to trade directly. At the same time, they destroy the server-side idea of peer-to-peer networking, which has existed since the advent of the Internet, because they need a central server to coordinate, rather than distributed in different parts of the world Many servers in peer-to-peer networking. This is exactly what Gnutella and Freenet constantly claim that they have created "pure" P2P, without P2P service of central server at all.

6. A brief introction to P2P if the word P2P (peer-to-peer) is only understood as a kind of network topology, it can not be called a new thing, because as early as many years ago, when the Internet was just born, it already existed, and the Internet at that time was a big network with P2P structure. People communicate with each other in a point-to-point way. There is no so-called server and client. This can be regarded as the most primitive situation of P2P. After decades of development, the resources on the Internet are graally enriched, and show an explosive growth trend. At the same time, the flow of resources tends to be centralized. A large number of open resources are provided on the Internet in the form of so-called server, and network applications also provide services in a centralized way, such as web, FTP, etc. It is undeniable that this centralized development has greatly promoted the popularization and application of the Internet, and has made the myth of today's Internet come true. However, in the only globally connected network, the centralized way makes the service lack of personality and full of strong business atmosphere. People visit several familiar Web servers of portal websites every day, send and receive e-mails on the mail server, and download files from various FTP servers, including ICQ, FTP, etc QQ and other instant messaging are also based on the typical client / server model. Today's Internet is completely under the control of the server. We do not deny that server has made an important contribution to the development of the Internet, because the "network society", like human society, has graally developed from the "primitive democracy" of the primitive society to the "feudal dictatorship" and finally to the modern democracy. The whole process is progressing. But we should see that the server centralized service mode has many technical disadvantages. One of the most important problems is that resources cannot be fully utilized. The biggest characteristic of Internet is global interconnection. The largest resource owning group on Internet is not server but client. It can be said that the client is the main body of the Internet. According to statistics, the total resources provided by global servers are less than 1% of the total Internet resources. In other words, the most and best resources actually exist in each of our PCs. With the development of hardware level, the performance and function of PC has far exceeded the original definition of PC. Many PCs can provide large storage capacity and high-speed computing power. People are eager to break the monopoly of server and have their own space on the Internet. P2P technology is born based on this goal. P2P technology is different from the server based application technology mentioned above. It is a new network communication technology based on P2P topology. Since its birth, the purpose of P2P is to break the monopoly of server, provide functions that server can't provide, make up for the deficiency of server, and make full use of and enrich the existing Internet resources. That is to say, P2P is not to abolish server fundamentally, but will coexist with server for a long time. Therefore, technically speaking, P2P technology is generally based on the mature TCP / IP protocol, and uses many mature technologies in server applications for reference. From the level of division, P2P should belong to the network application layer technology, and web and FTP applications are juxtaposed. However, P2P technology is more complex than these applications. P2P emphasizes one word very much: serverless. The proposal of serverless means that P2P technology divides Internet service delivery into three ways: server based, with server and non server. P2P is mainly for the latter two situations. Microsoft explains the word "serverless" as "no server, but works better with server". This may be a subtle summary of the concept of serverless“ "Server" is a common P2P solution. Napster, which has caused widespread controversy, edoney & eMule, which is very popular in Europe and America, and Jelawat and workslink developed by P2P fans in China, all belong to this kind of procts. At present, most of these procts are based on file sharing service, and have simple instant messaging function. One of the main features of this method is that the function of the server has been far degraded. Generally, it is only used as an index server, providing all peer and various file list search index services“ "Completely separated from server" is the focus and difficulty of P2P research, and also the ultimate goal of P2P technology. This way does not need the existence of server at all. All peers are equal. In P2P network, all resources are shared according to certain rules. At the same time, any peer can join a P2P network group at any time and any place. All of these do not need the cooperation and support of the server. Of course, works better with server. 2、 The application prospect of P2P technology many benefits brought by P2P technology are obvious. The biggest advantage is that resources will be fully utilized and shared to the maximum, and P2P technology also strengthens and improves many original applications. In the article "Introction to windows peer-to-peer networking", Microsoft listed several scenarios: real time communications (RTC), real-time communication n serverless instant messaging, serverless instant messaging (IM), which has become quite common in the world. Foreign ICQ, Yahoo Messenger, MSN Messenger and domestic QQ have attracted a large number of users. IM has become the most popular application on the Internet, mainly because it meets people's requirements for real-time communication. However, the current IM software is still based on the C / S model design, the user's account, friends list and other information are saved on the server, and even the user sometimes sent messages also need the help of the server to forward. If the server of the service provider breaks down or is being overhauled, many functions will be unavailable for a certain period of time. Serverless im does not need the support of server. As long as people form P2P network interconnection in some form (such as: workgroup), they can identify and communicate with each other, and the intermediate process does not need the help of server. This will not only greatly rece the operating costs of IM application providers, but also rece people's dependence on server stability. Whether you are on the Internet, or in an independent company LAN, or even at home, you can form a P2P network to communicate at any time. N real time matchmaking and game play, the development speed of real-time games and online games is also amazing, and now most of the new games provide online game function. However, similar to instant messaging applications, the online game based on C / S model also needs powerful game server support. Although there are many games that support local area connection, if we want to compete with overseas experts, we have to ask them to the server of the designated manufacturer, causing a lot of trouble and inconvenience. P2P technology allows any peer to establish a regional P2P network independently, which allows anyone on the Internet to join in at any time and play together. The concept of "collaborative work" within the project team is now more and more respected and valued. A very important reason is that the scale of the current project is constantly expanding, and it is not competent only by the strength of two or three people. In order to achieve "cooperative work" well, there must be corresponding software support. In the various components of office, the function of "collaborative work" has been added, and the corresponding function has been introced in visual studio.net, but these are still "collaborative work" based on C / S model. The collaborative work realized by P2P technology does not need the support of server, and can also be combined into a group to share information, raise problems, discuss solutions, etc., so as to provide better "collaborative work" ability. Sharing your files with other people is quite common. The functions mentioned above, such as eDonkey and eMule, have been realized. But what P2P technology really wants to provide is a file sharing capability without server. If we want to share an MP3 music file with a few friends far away in the United States, it is very troublesome to use software such as eDonkey to transfer this file, because these software only provide global sharing capability. If we use the file sharing software developed by P2P technology, as long as we simply form a P2P network, we can see each other's shared files and download them at any time. Moreover, this kind of file sharing is better than the current way. And these are not supported by the server. With the popularity of wireless applications, it is not new for mobile devices to surf the Internet and send and receive MMS and other applications. However, those who have a little knowledge of wireless services should know that our MMS can only be realized by forwarding from the operator server. Have you ever thought that when you come across a scene that excites you, you just need to aim at it with the camera of your mobile phone, and then you can directly transmit the scene to your friends in the form of video. These scenes, which seem to be only in science fiction movies, can be easily realized in P2P technology. Many people should have used the white board function in NetMeeting, including chat function in chatroom, which also supports many people chatting together, and everyone can see the chat information. However, this can only be realized by using server to store and forward in the middle, and many servers have restrictions on chat time and chat information, so they can't hang on the Internet all the time and see all the chat information at any time. P2P can realize 7 * 24 hours online interconnection in a workgroup, and distribute call information at any time. New members of this group can also see the previous information. This is very difficult for server based chat applications. N audio and video, audio and video are very popular now, and the application of network-based teleconference is also very common, which plays an important role in many occasions. In this system, a server in the main venue is used as the central control server to compress and encode the audio and video signals in the main venue, and then send them out through wired or wireless network, and decode and play them when they arrive at the sub venue. If you want to see the situation of the branch venue, you must constantly send the signal of the branch venue back to the central server of the main venue, and then it will be distributed to other branch venues. It can be seen that in the process of transfer, a lot of network transmission infrastructure is wasted, and the disadvantages of the / S model can not be avoided. P2P technology makes all the venues in an equal position. The signal of a conference hall will be broadcast to all conference halls at the same time. The conference system only needs to switch different reception signals to receive the situation of all conference halls. N distribution of proct updates: to distribute proct upgrade patches. After the proct is launched, patches are often needed to solve bugs or security risks, such as Microsoft service packs or update. However, the current method of patching is basically to let users download the patches released on the website and install the patches themselves. This will cause a lot of problems, the most serious problem is the user's response to the patch

7. P2P is the abbreviation of peer-to-peer Equal in status, ability, etc& quot; Colleagues & quot; And & quot; Partner & quot; And so on. In this way, P2P can be understood as & quot; Partner to partner & quot; Or peer to peer networking. At present, people think that it has a bright future in enhancing people's communication, file exchange, distributed computing and so on< br />
?? In short, P2P directly connects people and enables people to interact directly through the Internet. P2P makes communication on the network easier, more direct sharing and interaction, and truly eliminates middlemen. P2P means that people can directly connect to other users' computers and exchange files, instead of connecting to the server to browse and download as in the past. Another important feature of P2P is to change the Internet's current big website centered state and return to & quot; Decentralization & quot;, And give the power back to the user. P2P seems to be very new, but just as B2C and B2B transplant common things in the real world to the Internet, P2P is not new. In real life, we communicate face to face or by telephone according to P2P mode every day< br />
?? Even from the perspective of network, P2P is not a new concept. P2P is the foundation of the whole Internet architecture. TCP / IP, the most basic protocol of Internet, has no concept of client and server. All devices are the equal end of communication. Ten years ago, all systems on the Internet had both server and client functions. Of course, the later developed software based on TCP / IP does adopt the client / Server Structure: browser and web server, mail client and mail server. However, for servers, they are still peer-to-peer networking. Take e-mail as an example, there is not a huge and unique e-mail server on the Internet to handle all e-mails, but peer-to-peer e-mail servers cooperate with each other to send e-mails to the corresponding servers. In addition, email between users has always been a peer-to-peer contact channel.?? Of course, but in the past five years, the development of the Internet has at least distanced itself from P2P on the surface, and most of the nodes on the Internet can not communicate directly with other nodes. Napster awakens the peer-to-peer networking that is deeply behind the Internet. Napster's file sharing function is a common thing to share directory in LAN. But Napster's success has led people to realize that this kind of & quot; Peer to peer networking & quot; The possibility of expanding to the whole Internet. Of course, in the eyes of many people, Napster is not pure P2P, it still needs a central coordination mechanism< br />
?? In fact, many existing services on the network can be classified as P2P. Instant messaging systems such as ICQ, AOL Instant Messenger, Yahoo pager, MSN Messenger from Microsoft and OICQ in China are the most popular P2P applications. They allow users to communicate and exchange information and files with each other. The information exchange between users is not direct, it needs a server in the center to coordinate. However, these systems do not have such functions as search, which are very important for a large number of information sharing. The lack of this feature may be one of the reasons why instant messaging has appeared for a long time, but it has not been able to proce such an impact as Napster< br />
?? Another thing that can be classified as P2P is auction websites, such as eBay. When people summarize the mode of eBay, they use C2C. Is it a bit similar to P2P? EBay is a community that connects people and trades goods. Users can easily search for goods that other users sell. EBay offers some services to make the transaction go smoothly, but the transaction is directly between users. If & quot; Trading & quot; C2C is a special case of P2P, where people exchange goods with each other< br />
?? But if we look into it carefully, Napster and instant messaging give users the ability to communicate directly and eBay allows users to trade directly. At the same time, they destroy the idea of peer-to-peer networking on the server side, which has existed since the beginning of the Internet, because they all need a server located in the center to coordinate, rather than distributed in different parts of the world Many servers in peer-to-peer networking. It's also the constant claims of gnotella and Freenet that they created & quot; Pure & quot; There is no P2P service of the central server<

impact:

peer to peer: is the end of the read-only web?? Peer to peer allows you to participate in the Internet?? Peer to peer networking: make the network away from TV (peer-to-peer steering the Internet away from TV). As mentioned above, P2P is not a new idea. From some angles, it is even the most basic idea of the whole initial creation of the Internet.

8. P2P software is based on P2P technology

1. What is P2P

P2P is a technology, but it is more of an idea, which has the potential to change the whole Internet foundation<

(1) the concept of P2P

P2P is the abbreviation of peer-to-peer. In English, peer has the meanings of "peer", "colleague" and "partner". In this way, P2P can be understood as "partner to partner", or peer-to-peer networking. At present, people think that it has a bright future in enhancing people's communication, file exchange, distributed computing and so on

in short, P2P directly connects people and enables people to interact directly through the Internet. P2P makes communication on the network easier, more direct sharing and interaction, and truly eliminates middlemen. P2P means that people can directly connect to other users' computers and exchange files, instead of connecting to the server to browse and download as in the past. Another important feature of P2P is to change the Internet's current big website centered state, return to "decentralization", and return power to users. P2P seems to be very new, but just as B2C and B2B transplant common things in the real world to the Internet, P2P is not new. In real life, we communicate face to face or by telephone according to P2P mode every day

even from the perspective of network, P2P is not a new concept. P2P is the foundation of the overall Internet architecture. TCP / IP, the most basic protocol of Internet, has no concept of client and server. All devices are the equal end of communication. Ten years ago, all systems on the Internet had both server and client functions. Of course, the later developed software based on TCP / IP does adopt the client / Server Structure: browser and web server, mail client and mail server. However, for servers, they are still peer-to-peer networking. Take e-mail as an example, there is not a huge and unique e-mail server on the Internet to handle all e-mails, but peer-to-peer e-mail servers cooperate with each other to send e-mails to the corresponding servers. In addition, email between users is always a peer-to-peer communication channel. Of course, but in the past five years, the development of the Internet has at least distanced itself from P2P on the surface, and most of the nodes on the Internet can not communicate directly with other nodes. Napster awakens the peer-to-peer networking that is deeply behind the Internet. Napster's file sharing function is a common thing to share directory in LAN. But Napster's success has made people realize the possibility of extending this "peer-to-peer networking" to the whole Internet. Of course, in the eyes of many people, Napster is not pure P2P, it still needs a central coordination mechanism

in fact, many existing services on the network can be classified as P2P. Instant messaging systems such as ICQ, AOL Instant Messenger, Yahoo pager, MSN Messenger from Microsoft and OICQ in China are the most popular P2P applications. They allow users to communicate and exchange information and files with each other. The information exchange between users is not direct, it needs a server in the center to coordinate. However, these systems do not have such functions as search, which are very important for a large number of information sharing. The lack of this feature may be one of the reasons why instant messaging has appeared for a long time, but it has not been able to proce such an impact as Napster

another thing that can be classified as P2P is auction websites, such as eBay. When people summarize the mode of eBay, they use C2C. Is it a bit similar to P2P? EBay is a community that connects people and trades goods. Users can easily search for goods that other users sell. EBay offers some services to make the transaction go smoothly, but the transaction is directly between users. If the concept of "transaction" is extended, C2C is a special case of P2P, where people exchange goods with each other

but if we look into it carefully, Napster and instant messaging give users the ability to communicate directly and eBay allows users to trade directly. At the same time, they destroy the server-side idea of peer-to-peer networking, which has existed since the advent of the Internet, because they need a central server to coordinate, rather than distributed in different parts of the world Many servers in peer-to-peer networking. This is exactly what Gnutella and Freenet constantly claim that they have created "pure" P2P, without P2P service of central server at all<

(2) the origin of P2P: back to the essence of the Internet

if we look back, we will find that P2P is one of the essential characteristics of the Internet at the beginning of www. People build their own web pages and make links with each other. People surf the Internet along the links. At that time, the web was the real "Web". But when Yahoo! After the establishment of search engine and portal site with Lycos, people's way of surfing the Internet has been changed, and from then on people go to one place to get all the information. Remember_ blank"& gt; Sina once said that they were "target site" mode for a period of time, but if you ask one more question, now people read one by one_ blank"& gt; Is there a concept of "net" in Sina News? The biggest problem is that these sites control the flow of information, are full of outdated information, hinder real communication, or for many people, there are too many advertisements. P2P is to return control to users. People can share files, directories and even the whole hard disk through P2P. This kind of energy is very exciting. The things that we think are the most valuable, and all people share what they think is the most valuable. This will greatly enhance the value of information on the Internet. Is there the same excitement as when www just appeared? A little bit

because each peer represents the people after him, self-organized online communities are emerging. Different from the way portal site builds community from top to bottom, people will form community spontaneously

when people join the P2P network, everyone has equal opportunities, and everyone has the opportunity to easily create "content" on the network. Of course, there are still a few people who really create or provide content on the Internet. According to statistics, only 2% of Gnutella users provide content to other users. Even in the more active Usenet, only 7% of all users post articles. However, for the first time, P2P makes all people who surf the Internet have equal opportunities<

this paper attempts to reveal the impact of P2P in three sentences:

peer to peer: the end of the read-only web

peer to peer: allowing you to participate in the Internet again

peer to peer: keeping the network away from TV As mentioned above, P2P is not a new idea. From some perspectives, it is even the most basic idea of the whole Internet. Let's take a moment to review

the development of the Internet is no different from the development mode of many modern cutting-edge science and technology, that is, it is first formed in the military instry, and then transferred to the civilian field. The Internet originated from a very novel strategic idea: what should we do to prevent the enemy's destructive weapons from hitting the national military command and control center? The traditional method is to try every means to keep the enemy from knowing the exact location of the center, on the other hand, to improve the ability of the center to resist attack

but in today's era of nuclear weapons, the other side has a nuclear bomb that can blow up even a planet. Once the other side's defences are attacked, they will soon disappear. As long as there is a secret, there is always a way to find out the secret, so it is not a long-term solution to rely on the location of the secret center. In this case, the U.S. military personnel give full play to the reverse thinking, thinking that since it is impossible to effectively protect the center from attack for a long time, it is better not to set up a center at all

every base and even every computer can operate independently. In this way, there are countless centers. Unless the enemy really blows up the planet, one of the bases or computers will be damaged, and other bases or computers will not continue to function. It is this idea of "decentralization" that has become the most basic concept of the Internet

however, after the emergence of many technologies, they often do not develop completely according to the original design. The server / client architecture has graally become the mainstream of the Internet, and browsing has become the most important way for people to live on the Internet. Ordinary users of the Internet seem to be slowly degenerating and passively browsing the content created by big websites like TV viewers

People's main activities on the Internet are visiting such portal sites, reading news, participating in discussion groups and chatting. But this makes a feature of the designed Internet disappear - what happens if Yahoo interrupts its service for some reason? This assumption is not easy to see, but the chaos caused by hacker attacks on major websites at the beginning of the year seems to give us a clue of association

as mentioned above, Napster and instant messaging still need servers located in the center, so a sentence on Gnutella website may express the concept of "decentralization" contained in their promotion of "pure" P2P: Gnutella is designed to survive nuclear war

according to the description on its website, the attack on users in New York will only affect some users in that area at most, while Gnutella users in other places can still use it normally. Isn't this the initial ideal of the Internet<

(3) the revolution brought about by Napster

Napster was developed last year by Shawn fanning, who was only 18 years old. It provides services that allow music fans to exchange MP3 files. It is different from mp3.com, which has been put on the dock for free music download, that is, there is no song on the Napster server. Napster provides a new software for music fans to share song files on their hard disks, search for song files shared by other users, and download songs on the hard disks of other users who also use Napster service. Napster attracted 50 million users in a short period of time. In the end, it was pushed to the dock by the five major record companies for right infringement and became the focus of the world

perhaps there has never been an instry like the record instry, whose survival will be so seriously threatened by a small software. There has been a lot of discussion about the right issue caused by Napster, but it is worth spending more time to discuss it, because this case determines the future of P2P file sharing and how to deal with the right issue on the Internet in the future