||This article appears to be written like an advertisement. (December 2011)|
|Developer(s)||Thunder Networking Technologies (a.k.a. Xunlei Networking Technologies)|
|Stable release||18.104.22.16866 (Windows) 2.4.0 (Mac OS X) 1.3 (Android) (21 November 2013 (Windows) 27 February 2014 (Mac OS X) 23 August 2012 (Android)) [±]|
|Operating system||Microsoft Windows, Mac OS X, Android(Mobile)|
|Available in||Simplified Chinese, Traditional Chinese, English with a language pack|
|Type||Peer-to-peer file sharing|
|License||Closed source adware|
Xunlei (Chinese: 迅雷; pinyin: Xùn Léi; literally: "fast thunder") is a download manager and Peer-to-peer software developed by Thunder Networking Technologies (Chinese: 迅雷网络技术有限公司, formerly Sandai Technologies), supporting HTTP, FTP, eDonkey, and BitTorrent protocols. As of 2010[update], it was the most commonly used BitTorrent client in the world. On June 24 2014, it went public on the Nasdaq Stock Exchange, raising just shy of $88 million. 
The Xunlei download manager, generally called Xunlei, is the flagship product of Xunlei Corporation, which also supports Xunlei Kankan, a video-on-demand website, and other desktop software.
Through Xunlei, users can access a large portion of the files available on the Internet. Features in Xunlei includes a built-in browser, changeable skins, cloud storage, "offline" downloading, hi-speed downloading (only available for members), email service and more.
Xunlei is accompanied by a family of products including Xunlei 5, Mac Xunlei, Xunlei Mini, and Web Xunlei. As adware, Xunlei products feature banner advertisements, which can be disabled if logged in as a user (in the latest version).
Xunlei Kankan, also known as Kankan, is a video-on-demand service with a web interface as well as a client application. Xunlei Kankan is also available on mobile platforms including Android and iOS (including iPhone and Kankan HD for iPad).
Along with Xunlei 7 and Kankan, the company also produces software such as a gaming client, a graphics editor, game "accelerator", software manager, and a web photo viewer.
Concerns and criticisms
Content holders often find that users are downloading their material through Xunlei, and accuse Xunlei of helping, actively or passively, others to violate their copyrights. Xunlei claims that the product is only a tool, and that the company has no right to control how users use Xunlei.
As copyright protection has become more strict, Xunlei has attempted to protect itself from accusations of copyright violation. In 2007, Xunlei announced a new service that enables copyright owners to claim and protect their content on Xunlei's platform. Later, Kankan claimed to host only authorized content.
Xunlei is different from P2P tools in that it does not support active file sharing. While copyright advocates view Xunlei as a P2P tool that facilitates copyright violation, P2P advocates criticize Xunlei as a leech with much more downloading than uploading. Many pure P2P tools have blocked Xunlei, although this trend weakened after Xunlei began balancing the number of downloads and uploads.
Experience[whose? clarification needed] has shown that Xunlei version 0.1.0.0 refuses to upload any data for a torrent that has only two leechers (i.e. when the only seeder is offline). All Chinese ISPs limit BitTorrent bandwidth, as a result the Chinese users can't upload as the rest of the world. Furthermore, the 0.1.0.0 client sequentially requests pieces, which goes against the distributive nature of P2P.
Direct linking, or leeching, concerns many site owners, who may feel that the practice benefits Xunlei at their sites' expense. In 2006, Huajun, the leading download site in China, started blocking Xunlei along with many other downloading sites.
User agent imitation
Since many websites recognized and blocked Xunlei via user agent (UA) string, Xunlei began to use common browser's UA as camouflage. The default UA is:
Mozilla/5.0 (compatible; MSIE 6.0; Windows NT 5.0)
However if Xunlei determines it is blocked from a website, it will automatically change UA to imitate other browsers, such as:
Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729)
Xunlei shares files by default without additional notifications after installation. While Xunlei argues that this behavior is a common convention and that users can disable it, some users are still worried, since Xunlei's sharing policy is unclear. Investigations[by whom?] have revealed that Xunlei only shares files downloaded through Xunlei. Moving or renaming files may automatically disable sharing.[clarification needed]
Although not widely reported, Xunlei client has been discovered spreading the malware Win32/KanKan to thousands of Chinese Windows PCs and Android devices. In 2013 the company admitted its employees bundled malware into Xunlei client.
- Check Update [Check for updates], 粤 Guangdong
- Van Der Sar, Ernesto. "Thunder Blasts uTorrent’s Market Share Away". TorrentFreak. Archived from the original on 15 September 2011. Retrieved 15 September 2011.
- "Xunlei IPO on Nasdaq raises $88m". Retrieved 24 June 2014.
- 落落 (27 March 2013). "吐槽迅雷……". Retrieved 27 April 2014.
- Gibbs, Samuel. "Google-backed BitTorrent client spread malware to Windows PCs and Android devices". TheGuardian.com. Retrieved 28 March 2014.
- Kovacs, Eduard. "Company Admits Its Employees Bundled Malware with Xunlei Download Manager". Softpedia. Retrieved 14 April 2014.
- Official website
- English Version of Thunder Mini
- Baidu's Most Searched Software List
- Malware Win32/KanKan