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🌐 | [Breaking news] Ibaraki Prefectural Police, 3 men suspected of illegally uploading Gundam movies to the internet

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[Breaking news] Ibaraki Prefectural Police sent documents to three suspected men who illegally uploaded Gundam movies to the Internet

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From around June 6th to around 14th, the alleged document sending was carried out on a computer containing the work information of the anime movie "Mobile Suit Gundam: Hathaway of the Flash", which is copyrighted by "Sunrise" (Tokyo). Suspected of infringing the company's copyright by launching connection and file sharing software, making the movie publicly available to an unspecified number of users.

Ibaraki Prefectural Police Hitachinaka Station, Hitachi Station, Furukawa Station and Prefectural Police Cyber ​​... → Continue reading

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File sharing software

File sharing softwareWhat is (File Today Software)?インターネットWith an unspecified number of usersFileSo-calledFile sharingSoftware for[1]..In this article, software and web services that share files among an unspecified number of people (Uploader) Will be explained.For software that shares files only with a limited number of people or within the organization (document sharing)Groupware,online storageSee (also known as cloud storage).


File sharing software is a mechanism that configures a dedicated network by communicating with a dedicated protocol defined by the software, and exchanges files shared with an unspecified number of computers connected to that network. Software with.The method was initiallyHTTP,FTPlikeUploaderIt was a method equivalent to, but in the 21st century,Peer to PeerThose using technology (P2P technology) have become mainstream.

2001 After that, high-speed large-capacity communication (Broadband internet connection) Has developed worldwide, and the number of users of file sharing software has also increased significantly.

In Japan, the main thing was to exchange files one-on-one at the beginning.File exchange softwareIs called,WinnyAfter that, after multiple-to-multiple exchanges became commonFile sharing softwareAlso called.In Japan, the usage rate once exceeded 9%, but in 2010 the usage rate decreased to 5.8%.[2].


The uploader isHTTP,FTPlikeCommunication protocolShare using.

Uploader features

  • Many protocols like HTTP and FTPWeb browserBy standardSupportBecause it has been newlysoftwareTheInstallYou don't have to.
  • It is easier to manage than distribution using Peer to Peer technology.It is the most advantageous in terms of real-time performance, such as file changes and management being reflected immediately, and downloading starting immediately after a request.
  • It has the advantage of making it easy to see who downloaded the file.
  • There is no anonymity as a flip side of the fact that the server can keep track of all searches and transfers.
  • It largely depends on the processing power of the server and the performance (line speed, reliability) of the line to which the server is connected.

Using Peer to Peer technology

Peer to Peer technology (hereinafter referred to as P2P) is characterized in that peers (Peer, peers) communicate with each other.In other words, it is a technology that downloads a file from another computer without distinguishing between a server and a client, and at the same time sends (uploads) a part of the downloaded file to another computer. Some people demand anonymity for file sharing software that uses P2P, which tends to be higher than the client-server model.However, from the perspective of the file uploader, it is up to each person to see this as an advantage or a disadvantage.


P2P technology You can use to hide who published the data.It is an advantage for criminals who share illegal content, but it is a disadvantage for content providers.

Difficulty of deletion control

P2P technology The problem with using is that once the data is published, it will continue to be published as long as there is a node with a cache.

Difficulty in security control

P2P technology If you use, there is a risk that personal information on the end user's PC will be leaked without the user's awareness. In the Winny incident, illegal content and virus-containing data were frequently released, which became a social problem.

Load on the internet

P2P technology When using, the line load of general users increases and the bandwidth of the backbone line of the ISP is used significantly, so it has become disliked by the ISP.

How to hold data information for P2P type software

In order to answer inquiries such as "Is the data containing this keyword shared?" And "Who has this data?", The server may have the data and the data may be distributed to each node. There are three types, one is to have it and the other is to distribute it to a specific selected node.

Hybrid P2P

A mechanism that conveys information on shared data to the server, manages it on the server, and exchanges actual data between nodes.

BitTorrent,Napster,WinMXEtc. is this method.

Pure P2P

A mechanism for sharing data information between participating computers in a distributed manner and exchanging actual data between computers.

Gnutella,freenet,Winny,ShareAnd so on, this method.

Supernode type P2P

A mechanism in which a specific selected node (supernode) shares the information of the data to be shared.

KaZaA, Etc. is this method.

Anonymization technology in P2P networks

Therefore, in actual P2P,How to know the IP address of the other party, Is an important point.In recent P2P, it is possible to identify a communication partner by a name meaningful to a person, such as a content title, a search keyword, or a channel name of a broadcasting station, and communicate with the user.In this sense, the communication network using the P2P method isOverlay networkIt can be seen as (Overlay Network) (hereinafter abbreviated as OLN).NormalIP networkOn top of that, it means creating another network of nodes that meet specific needs.

To be more specific, for exampleWinnyThen, specify "the person who has the cache" by "the name of the desired content" and communicate, for example.SkypeThen, the "nickname" is used to identify the "person corresponding to the nickname" and communicate.When generalized, the operation is to discover a "person who has data corresponding to the key" using the "key" as a clue and communicate with the other party. Information that connects "key" and "data" in pairsIndex informationCalled.Normally, "data" is stored as the IP address of the person who has the data. (The index iskey-value pairIt may be called. ) In P2P, how to manage index information is important.

Challenges and issues

Depending on the contents of the shared file, it may be illegal, and there is no end to the arrests due to cyber patrols and simultaneous arrests using the P2P monitoring system by the police.[3]..Breakdown of persons arrested for file sharing software in 2013 in Japan[4]66% are copyright-related, 19% are obscene materials, and 15% are in violation of the Child Pornography Prohibition Law.By software used, Share is 50%, Perfect Dark is 20%, Cabos is 11%, µTorrent is 11%, WinMX is 7%, and emule is 1%.

Copyright issue

From the point that it can be easily sharedCopyrightThere is also a problem of sharing data with limited replication.

File sharing software first became software that was questioned about copyright issuesNapsterThere is.1999 OctoberToRIAASues Napster[5], Napster argued that it was legal to share for non-commercial purposes, but the U.S. District Court issued an order to suspend services.[6], Napster continued to argue against this, but in July 2001, Napster as a file sharing software ended its service due to a system failure.[7].

Winny,ShareFile sharing software such as, encrypts files, sends and receives data, and shares files.Therefore, it is difficult to identify the distributor, and there are many people who illegally exchange copyrighted music, movies, and commercial software. 2014 Survey by Computer Software Copyright Association (ACCS) and Fraudulent Commodity Countermeasures Council (ACA)[8]According to the report, the distribution of files that clearly infringe copyright, such as music, video, and programs, is 39.29% for Winny, 46.31% for Share, 60.13% for Perfect Dark, 52.30% for Gnutella, and 73.03% for BitTorrent. Become.

Winny was very popular in Japan, but the developers of Winny have been arrested and crackdowns on users are progressing.In response to that, software called Share, which works with a mechanism similar to Winny, was developed.Currently, the mechanism of encryption and anonymization for both Winny and Share has been elucidated, and it is possible to identify the distributor in principle.However, since identification requires continuous monitoring of the entire network, it is not possible to identify the distributor for files that existed before the start of monitoring or that originated from a node before being monitored.

Movement to eliminate copyright permission for shared files

In Sweden2005 A new law introduced in June made it illegal to share files such as software and movies over the Internet.As a result, the one million file-sharing people quickly became criminals.In response to these movements, we promise to legalize file sharing.Pirate partyWas formed.The Pirate Party was quickly picked up by Swedish and foreign newspapers.

Inspired by the activities of the Swedish Pirate Party, in more than 40 countriesPirate partyHas been formed and is active.[9]

2009 Conducted in JanuaryEuropean Parliament electionsIn, the Pirate Party has won one seat.

In particularGerman pirate partyThe momentum of the approval rating increase was tremendous, and it was held in September 2011.BerlinFor the first time in a city council election in (Metropolitan County), he won 5 seats with 8.9%, which exceeds the 15% vote required to obtain seats.Great leap forward with the first seat at the state legislature level[10][11].

Even at the national level, according to local mediaGerman pirate partyApproval rating has risen, saying that the German Pirate Party is likely to win a seat in the next national election.[12].

2011 January,European ParliamentHolds 55 seats in the 4th parliamentary groupEuropean Green Group/European Freedom FederationBut for personal useLegalization of file sharing,DRM (Digital Rights Management)Complete ban,Copyright protection period reduced to 5 yearsExpressed to ask to do[13].European Green Group/European Freedom FederationSwedenPirate partyBelongs to.

However, there are many calls for relaxation of copyright protection in this way, and even though copyright holders may individually relax the scope of permission, copyright protection is the foundation of the industry by copyrighted works, so TPP negotiations Needless to say, the overall protection period has been extended, and the crackdown on protection and piracy has been strengthened.


As a security issuekeyThere is a safety issue.Even in a well-known P2P system (eg winny), certificate the public key (AuthenticationSome are encrypted and signed without (see), but these have no security implications.On the other hand, if you certificate it, you can only keep the data confidential, but of course you will not be anonymous (from the definition of certificate).

Some have touted that encryption ensures data confidentiality and anonymity, but encryption (using) can only conceal data when the public key is certificated, and encryption is in the first place. It is not intended to ensure anonymity.

CryptographyAs is well known, in principle it is not possible to create a secure method without certificating the public key (spoofing, dual role,man-in-the-middle attackEtc.).Unless the public key is certified, the same problem will occur even if it is used in combination with a digital signature.

またCommon key cryptographyIt is not secure whether you use the method or use public key cryptography and symmetric key cryptography together.The problem cannot be solved by using symmetric key cryptography alone, and the above-mentioned certificate problem occurs when it is used in combination with public key cryptography.

Secret sharingThe same applies when (onion routing using) is used.

However, it has the effect of dazzling amateurs and gaining time until a decryption program can be created.However, once the decoding program is scattered, there is a problem that even an amateur can decode it by using the decoding program.

Virus infection

As one of the network security problemsExposed virusIncludingComputer virusThere is something that infects.

P2P applications installed on your computer can be used for any purpose or purpose.インターネットAgainstportOpenserverIn many cases, it behaves like a target.again,clientIn any case, even if it's just a typical behavior, it's an applicationBuffer overflowEtc.Security holeIf there is, the applications willAlways connectedBecause it is often doneworm,Computer virusEtc. have a vulnerability that spreads rapidly to the P2P net.actuallyWinny,ShareFrom a computer on whichCase of leakage of personal informationAnd confidential information leakage cases are occurring frequently.

Virus infection and personal information leakage in Winny etc. are not due to vulnerabilities in P2P software such as Winny, but can be dealt with if security measures equivalent to those of ordinary viruses are taken.

In addition, since many machines are always in operation, it exploits vulnerabilities in P2P software.BotnetWas built, Spam mailSend orDDoSThere is also the danger of being used as a springboard for attacks.[14] Therefore, it is better to avoid software that has stopped updating or software that has been left unfixed for serious vulnerabilities.

History of file sharing software

This section describes shared software using P2P.


NapsterIs a software and service for music sharing, released in January 1999.This service isMP3I was able to share the file.P2PIt was a pioneer of file sharing software using models, and became the first P2P file sharing software that gained many users.Since it does not support Japanese, it was hardly popular in Japan.RIAAThe service was suspended in July 2000 after being sued by the company and losing the case.As a company and brand, it continued as a music distribution service in another industry.

File transfer is performed by P2P, but file search and node matching are centrally managed by a dedicated server.Hybrid P2PThe model is adopted.Therefore, if the dedicated server is stopped, it will not function at all.The dedicated server will be the one prepared by Napster.It has a problem that access is concentrated on the node with popular files and the transfer is slow.


最初 のGnutellaThe clientAOLCompanyNullsoftIt was developed silently by employees of the department and released in March 2000.This was immediately discontinued by AOL, but the protocol was elucidated by analysis of this client, and various compatible clients are still being developed.Even now, Gnutella standard client softwareLimeWireThere are many users.

How is it different from Napster?Pure P2PIt is adopting a model.In addition to the conventional file transfer, file search and node matching are also realized by P2P, eliminating the need for a dedicated server.Because it doesn't rely on a dedicated server like this, the Gnutella network is extremely fault tolerant, and once it starts working, it's difficult to stop.


WinMXWas published in 2001.Multibyte characterIt became the first popular file sharing software in Japan because it supports. ((UnicodeIt is unknown whether it corresponds to. ) It also has a high-performance chat function, and a unique community is born.There was also a polite commentary by the magazine, and the introduction by beginners increased and the base of users expanded.

In November 2001, users were arrested for copyright infringement in Japan, and the following year, Winny, which will be described later, appeared, and it was said that the number of users started to decrease.ACCSSurvey conducted by[15]According to the report, in January 2003, more than 1% of "current users" answered that they "have used MX", and after that, although it gradually decreased, it remained in the top position until the 8 survey. It continued to occupy.This is the first time in the world that a user of file sharing software has been arrested.

2005 year 9 month,Judgment issued by the U.S. Supreme CourtWill shut down the official server.However, immediately after the official server was closed, a volunteer successor server was launched, and the MX community continues to decline even now.

With Napster compatible protocolHybrid P2PThe model is adopted.In addition to the official server (successor server), there are also some servers installed by individuals as dedicated servers for file search and node matching.


BitTorrentIs a protocol published in 2001.It is extremely efficient and is most often used in legal applications.In addition to having many clients, some web browsers and network devices are compatible. Due to the decline of WinMX, many overseas users have switched to BitTorrent.

Whereas traditional file-sharing software only uploads explicitly specified files, BitTorrent clients are required to automatically upload downloaded files as well.As a result, the concentration of access to nodes with popular files is minimized, and the more popular files are, the faster they can be transferred, resulting in efficient file sharing.

BitTorrentHybrid P2PA model is adopted, and node matching is performed by a dedicated server, but unlike Napster, it does not have a file search function and is devoted to file transfer.The user needs to prepare one corresponding torrent file for each file he wants to download.Anyone can install a dedicated server, and there are many servers, but since it is recorded in the torrent file, the user does not need to be aware of it.Most torrent files are distributed on websites, and many sites collect torrent files and add a search function.

Most of the file-sharing software currently in use is from Torrent.

Note: In Japan, there are cases where you were arrested just by collecting links to torrent files and torrent files corresponding to infringing files and illegal pornographic files and publishing a site with a search function. ..In particular, the display of obscene materials and violations of the Child Pornography Prohibition Law are not guilty of an antragsdelikt, and are therefore subject to simultaneous crackdowns.


WinnyIs a Japanese-made file sharing software released in May 2002, and is also a pioneer of anonymous file sharing software. It is said that the arrest of WinMX users caused a period of turmoil centered on users who shared illegally, and many users switched to Winny, which has anonymity. According to the ACCS fact-finding survey, 5% of respondents said they had used it in 2003, but in 22.8, 2004% said they used it most often (WinMX of the same year was 40.3%).After that, it turned to a declining trend, but in 57.6 after the above-mentioned WinMX official server was closed, "mainly used" was 2006%, exceeding WinMX (33.3%) for the first time, the highest in Japan.

Automatically download files that meet the conditions from one end地引For the first time, I proposed a usage method called.BBSIt also had a function and was used for that purpose.Multibyte characterAlthough it corresponds toUnicodeIt is not widely used overseas because it does not support the above, the source code is not open to the public, and it is difficult to localize.Although anonymity was trusted at the time, Winny's development stopped on November 2003, 11, when a user arrested him for copyright infringement.The following year, on May 27, 2004, the developer's for helping with copyright infringement.Kaneko IsamuWas also arrested.Kaneko was acquitted in December 2011, but died in July 12.[16][17].

Now[When?]Although the analysis is progressing and the anonymity has been broken, Winny has attracted attention because it is characteristic in various points including technical matters.First practical in JapanPure P2POne of them is that it was network software. Many software was influenced by Winny.

It is now quite declining.

Pure P2PAlthough the model is adopted, the file search function is more efficient than Gnutella and others.When transferring, instead of transferring the file as it is, it converts it to data called a cache (or while converting), then transfers it, and restores it as needed.At that time, anonymity was ensured by relaying the transfer with a certain probability. Like BitTorrent, the downloaded cache is automatically uploaded, but the cache is managed by Winny in principle and the user is not involved, so it is more thorough than BitTorrent.Since the cache is encrypted, users do not know what their node relayed. (Actually, there is a way to know with a specific tool.)

Current file sharing standard

Software that incorporates a file sharing (exchange) system as part of its functions


  1. ^ "What is file sharing software? | Technology related to information security | Basic knowledge | Information security site for the people". Ministry of Internal Affairs and Communications. 2014/9/14Browse.
  2. ^ 2011 pages of the Asahi Shimbun morning edition on January 2, 5
  3. ^ "Copyright infringement case”(May 2014, 1). 2014/1/17Browse.
  4. ^ "Even now, about 15 to 20 people use P2P file sharing software, NetAgent survey”(May 2014, 1). 2014/1/17Browse.
  5. ^ Trends in Napster,FoundationDigital Media Association
  6. ^ US District Court orders music exchange software Napster to stop service, ImpressWatch, July 2000, 7
  7. ^ Napster system failure, file exchange service suspended, ImpressWatch, July 2001, 7
  8. ^ Results of "Survey on the actual use of file sharing software (crawling survey)", ACCS
  9. ^ "Piratenpartij presenteert verkiezingsprogramma”(Dutch). 3VOOR12 NL (May 2010, 5). 2010/5/27Browse.
  10. ^ Wahl in Berlin(German)Spiegel
  11. ^ . Sankei Shimbun(November 2011, 10). http://sankei.jp.msn.com/world/news/110919/erp11091920360004-n1.htm Pirate Party makes a big leap forward in Berlin city council election-MSN Sankei News 2011/10/10Browse. 
  12. ^ .. (March 2011, 9). http://www.tagesschau.de/inland/deutschlandtrend1386.html ARD-DeutschlandTrend: Piraten obenauf --FDP auf Rekordtief 2011/10/10Browse. 
  13. ^ . Ernesto. (October 2011, 10). http://torrentfreak.com/european-greens-want-to-legalize-file-sharing-ban-drm-111007/ European Greens Want to Legalize File-Sharing, Ban DRM 2011/10/10Browse. 
  14. ^ Invisible Spider Xunlei Eats the World-The Day The World's Largest P2P Network Becomes Anonymous Ultimate Weapon
  15. ^ CorporationComputer Software Copyright Association"Fact-finding survey of file exchange software usage" by (ACCS) (Survey Report-Activity Report-ACCS)Than
  16. ^ http://ascii.jp/elem/000/000/658/658282/
  17. ^ http://sankei.jp.msn.com/west/west_affairs/news/130708/waf13070820540025-n1.htm

Related item

Suspected document sending


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