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Pirate decryption most often refers to the decryption, or decoding, of pay TV or pay radio signals without permission from the original broadcaster. The term "pirate" in this case is used in the sense of copyright infringement and has little or nothing to do with sea piracy, nor with pirate radio, which involved the operation of a small broadcast radio station without lawfully obtaining a license to transmit. The MPAA and other groups which lobby in favour of intellectual property (specifically copyright and trademark) regulations have labelled such decryption as "signal theft"〔(mpaa.org ), Motion Picture Association of America - Who Are Movie Thieves?〕 even though there is no direct tangible loss on the part of the original broadcaster, arguing that losing out on a potential chance to profit from a consumer's subscription fees counts as a loss of actual profit. == History == The concept of pay TV involves a broadcaster deliberately transmitting signals in a non-standard, scrambled or encrypted format in order to charge viewers a subscription fee for the use of a special decoder needed to receive the scrambled broadcast signal. Early pay TV broadcasts in countries such as the United States used standard over-the-air transmitters; many restrictions applied as anti-siphoning laws were enacted to prevent broadcasters of scrambled signals from engaging in activities to harm the development of standard free-to-air commercial broadcasting. Scrambled signals were limited to large communities which already had a certain minimum number of unencrypted broadcast stations, relegated to certain frequencies. Restrictions were placed on access of pay TV broadcasters to content such as recent feature films in order to give free TV broadcasters a chance to air these programs before they were siphoned away by pay channels. Under these conditions, the pay TV concept was very slow to become commercially viable; most television and radio broadcasts remained in-the-clear and were funded by commercial advertising, individual and corporate donations to educational broadcasters, direct funding by governments or license fees charged to the owners of receiving apparatus (the BBC in the UK, for example). Pay TV only began to become common after the widespread installation of cable television systems in the 1970s and 1980s; early premium channels were most often movie broadcasters such as the US-based Home Box Office and Cinemax, both currently owned by Time Warner. Signals were obtained for distribution by cable companies using C-band satellite dish antennae of up to ten feet in diameter; the first satellite signals were originally unencrypted as extremely few individual end-users could afford the large and expensive satellite receiving apparatus. As satellite dishes became smaller and more affordable, most satellite signal providers adopted various forms of encryption in order to limit reception to certain groups (such as hotels, cable companies, or paid subscribers) or to specific political regions. Early encryption attempts such as Videocipher II were common targets for pirate decryption as dismayed viewers saw large amounts of formerly-unencrypted programming vanishing. Nowadays some free-to-air satellite content in the USA still remains, but many of the channels still in the clear are ethnic channels, local over-the-air TV stations, international broadcasters, religious programming, backfeeds of network programming destined to local TV stations or signals uplinked from mobile satellite trucks to provide live news and sports coverage. Specialty channels and premium movie channels are most often encrypted; in most countries, broadcasts containing explicit pornography must always be encrypted to prevent reception by those who wish not to be exposed to this sort of "adult content." 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pirate decryption」の詳細全文を読む スポンサード リンク
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