Perfect Dark (P2P)
|This article relies on references to primary sources. (October 2007)|
|Developer(s)||Kaichō (会長?, "The Chairman")|
|Stable release||version 1.17 "wrath" / February 13, 2014|
|Operating system||Microsoft Windows
Wine officially supported
|Size||less than 2 MB|
|Available in||English, japanese|
- This article is about the Japanese P2P file-sharing client. For other uses, see Perfect Dark (disambiguation).
Perfect Dark (パーフェクトダーク?) is a peer-to-peer file-sharing (P2P) application from Japan designed for use with Microsoft Windows (not to be confused with the video game franchise Perfect Dark). It was launched in 2006. Its author is known by the pseudonym Kaichō (会長?, lit. "The Chairman"). Perfect Dark was developed with the intention for it to be the successor to both Winny and Share.
As of version 1.02, code-named "STAND ALONE COMPLEX", there is support for the program to run in English, an option that can be selected when the program is installed.
Perfect Dark is still being actively developed. The author does not ask that the program's users at this point become dedicated "users" of the software. Instead, the author asks them to participate in the test phase. Through this test phase, the author hopes for bug reports and discussion that will help shape Perfect Dark into a better program.
Perfect Dark has higher bandwidth and hard drive space requirements than its predecessors Winny and Share. The minimum upload speed is 100 KB/sec, and it requires at minimum 40 GB of hard drive space for its "Unity" folder (a huge distributed hash table used as a distributed data store).
Like other Japanese sharing software, Perfect Dark has its own proprietary P2P network called "Unity".
One of the biggest characteristics of Perfect Dark is its powerful search capability. By using distributed hash tables, search performance is greatly improved compared to Winny or Share, making it unnecessary to rely on the construction of node clusters. This frees users from inputting or switching cluster keywords and also enables users to search for files of different genres at the same time. This is in contrast to Winny and Share, where cluster keywords, such as "DVDISO" or "アニメ"/"anime" are used to specify what types of files the user is searching for. These keywords segregate the network and introduce delays when the user changes to them.
Perfect Dark requires more network bandwidth and hard disk space than Winny or Share, forcing a fairer load on all users. If a user does not have Perfect Dark configured with the proper settings or if the user is unable to support the settings, download rates will be restricted and priority will be given to other users. This is intended to increase the retention rate of the Perfect Dark network.
Since version 1.02 Perfect Dark has an option to automatically update itself.
Perfect Dark includes an original feature named "flow": a window where text lines wrote by users scroll. Each user can write one little message (few lines and columns), and it will be displayed to the other peers using the flow feature.
The author implements an architecture called DKT+DHT+DU in the design of the network. There are other features besides file sharing such as a simple bulletin board.
"DKT" is mainly for providing effective file searching while "DHT" and "DU" is used for effective file sharing and enhancing anonymity.
The anonymity relies on a mixnet where traffic is forwarded according to certain probability, as well as the deniability of the distributed data storage ("Unity") which is stored and transferred in encrypted blocks while the keys are separately distributed .
Published files and boards (including automatic updates from the author, where enabled) are usually signed with 160-bit ECDSA signatures. Automatic updates of the software are additionally protected with a 2048-bit RSA signature.
The author believes that initially, a layer of obscurity due to the closed-source nature of the program will frustrate attempted attacks on its anonymity, as well as deter "free riders" and junk files degrading the network. However, the author has stated that it may become open-source in the future should an acceptable solution to these problems be found.
The Japanese security firm NetAgent is claiming (2010) that they have created software capable of deciphering encrypted information such as the IP address of the original computer uploading a file as well as the file name and other details of Perfect Dark. · 
- A Perfect Dark user was arrested for the first time on 27 January 2010. The user had been uploading and sharing an episode of the Japanese animation TV series Fullmetal Alchemist: Brotherhood with Perfect Dark and was charged with breach of copyright law.
- On 10 June 2010, a second user, a 43-year-old man, was arrested on the suspicion of uploading roughly one thousand copyrighted files including the Big Windup! anime series.
- On 8 October 2010, a 42-year-old woman was arrested for uploading the Mitsudomoe anime TV series.
- (Japanese) Official web site, user guide and installation instructions (2014)
- (Japanese) Ancient official web site (2006-2007)
- (English) Web page in English that describe the software
- (Japanese) Slashdot.jp article about Perfect Dark (in Japanese) 2006
- (None) PerfectDark.Org Russian hash-collection of Perfect Dark.
- (English) http://anonymous-p2p.org/perfect_dark.html
- (Japanese) Perfect Dark node list
- Another Perfect Dark node list
- "AppsThatSupportWine - The Official Wine Wiki". Wiki.winehq.org. 2011-11-10. Retrieved 2012-03-19.
- 次世代P2P、perfect dark - cyber205 の日記
- The Perfect Dark investigation service (Japanese)
- Male Arrested in Japan for Uploading via Perfect Dark (English)
- 2nd Man Arrested for Uploading Anime via Perfect Dark (English)
- Woman Arrested for Uploading Anime via Perfect Dark