Pirate decryption is the decryption, or decoding, of pay TV or pay radio signals without permission from the original broadcaster. The term "pirate" is used in the sense of copyright infringement. The MPA 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? and object to it, 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 or pay television 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 Warner Bros. Discovery. 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 be encrypted to prevent accidental viewing.
Technical issues Initial attempts to encrypt broadcast signals were based on analogue techniques of questionable security, the most common being one or a combination of techniques such as: Weakening or attenuating specific portions of the video signal, typically those required to maintain synchronization. Inverting video signals so that white becomes black (and vice versa). Adding an interfering signal at one specific frequency which could be simply filtered out at a suitably equipped receiver. Moving the audio portion of the signal to some other frequency or sending it in a non-standard format.
These systems were designed to provide decoders to cable operators at low cost; a serious tradeoff was made in security. Some analogue decoders were addressable so that cable companies could turn channels on or off remotely, but this only gave the cable companies control of their own descramblers — valuable if needed to deactivate a stolen cable company decoder but useless against hardware designed by signal pirates.
The first encryption methods used for big-dish satellite systems used a hybrid approach; analogue video and digital encrypted audio. This approach was somewhat more secure, but not completely free of problems due to piracy of video signals.
Digital TV services, by nature can more easily implement encryption technologies. When first introduced, digital DBS broadcasts were touted as being secure enough to put an end to piracy once and for all. Often these claims would be made in press releases.
The enthusiasm was short-lived. In theory the system was an ideal solution, but some corners had been cut in the initial implementations in the rush to launch the service. The first US DirecTV smart cards were based on the BSkyB VideoCrypt card known as the Sky 09 card. The Sky 09 card had been introduced in 1994 as a replacement for the compromised Sky 07 card. The former had been totally compromised in Europe at the time (1995). The countermeasure employed by NDS Group, the designers of the VideoCrypt system was to issue a new smartcard (known as the Sky 10 card) that included an ASIC in addition to the card's microcontroller. This innovation made it harder for pirates to manufacture pirate VideoCrypt cards. Previously, the program in the Sky card's microcontroller could be rewritten for other microcontrollers without too much difficulty. The addition of an ASIC took the battle between the system designers and pirates to another level and it bought BSkyB at least six months of almost piracy-free broadcasting before the pirate Sky 10 cards appeared on the market in 1996. Initial pirate Sky 10 cards had an implementation of this ASIC but once supplies ran out, pirates resorted to extracting the ASICs from deactivated Sky cards and reusing them.
The first US DirecTV "F" card did not contain an ASIC and it was quickly compromised. Pirate DirecTV cards based on microcontrollers that were often ironically more secure than those used in the official card became a major problem for DirecTV. Similar errors had been made by the developers of the UK's terrestrial digital Xtraview Encryption System, which provided no encryption and relied on hiding channels from listings.
The DirecTV "F" card was replaced with the "H" card, which contained an ASIC to handle decryption. However, due to similarities between the "H" and other existing cards, it became apparent that while the signal could not be received without the card and its ASIC, the card itself was vulnerable to tampering by reprogramming it to add channel tiers or additional programming, which allowed them to be viewed without paying.
Two more card swaps would be necessary before DirecTV could reduce piracy by a significant amount; a number of other providers are also in the middle of swapping out all of their subscribers' smartcards due to compromised encryption methods or technology.
A number of vulnerabilities exist even with digital encryption:
The same algorithm is used, potentially, for millions of subscribed receivers and or smartcards. The designers have the choice of using their own custom, secret algorithm or using a publicly tested one. The first approach is often referred to as security by obscurity. With many digital TV encryption systems relying on smartcards for their security, any compromise of the smartcard would require a complete replacement of all smartcards being used. That could potentially involve the replacement of millions of smartcards. On a system with a low number of subscribers, the smartcards can be replaced periodically. However, as the number of subscribers grows, the cost of replacing the smartcards and the logistics of the replacement encourages the system users to try to get the longest use out of the smartcards before replacement. The chances of a fatal compromise on the smartcard increases as the time between replacement increases. Any compromise of the smartcard or algorithm will become public quickly. Computers and Internet can be used to make crucial design details publicly available. Internet sites may be located offshore in countries where local laws permit the information and software to be distributed openly; some of the more notorious software distributed to pirates ranges from NagraEdit (a program intended to edit the information stored on Swiss-designed Kudelski NagraVision 1 smartcards) to firmware which may be used to reprogram some free-to-air set-top boxes or desktop PCs equipped with Digital Video Broadcasting (DVB) tuner cards to permit them to decode encrypted broadcasts. The secrecy of any algorithm is only as trustworthy as the people with access to the algorithm; if any of them were to divulge any of the design secrets, every card with the compromised algorithm may need to be replaced for security to be restored. In some cases, outside personnel (such as those employed by lawyers in the NDS vs. DirecTV intellectual property lawsuit over the P4 card design) may obtain access to key and very sensitive information, increasing the risk of the information being leaked for potential use by pirates. If less secure encryption is used due to processor limitations on the smartcards, the system is vulnerable to cryptographic attack using distributed processing. While most secure Internet and online banking transactions require 128-bit encryption, 56-bit codes are not uncommon in video encryption. A cryptographic attack against a 56-bit DES code would still be prohibitively time-consuming on a single processor. A distributed approach in which many users each run software to scan just a portion of the possible combinations, then upload results to one or more central points on a network such as the Internet, may provide information of value to pirates who wish to break security. Distributed processing attacks were used, successfully in some cases, against the D2-MAC/EuroCrypt system used in Europe during the 1990s. The resources available for reverse engineering increase significantly if a direct competitor with smartcard manufacturing knowledge were to attempt to maliciously compromise the system. Integrated circuits may be vulnerable to microprobing or analysis under an electron microscope once acid or chemical means have been used to expose the bare silicon circuitry. One lawsuit has already been launched by Canal+, dropped as the result of the one billion Euro deal to sell TelePiu (Italy), then continued by Echostar (USA). The suit alleged that competitor NDS Group had maliciously used reverse engineering to obtain the computer programs contained within various pay-TV smartcards (including SECA and Nagra cards) and allowed the results to be posted to Internet sites such as the notorious DR7.com.
On May 15, 2008, a jury in the Echostar vs NDS civil lawsuit (8:2003cv00950) awarded Echostar just over US$1,500 in damages; Echostar originally sought $1 billion in damages from NDS. However, a jury was not convinced of the allegations Echostar had made against NDS and awarded damages only for the factual claims that were proven and for which the jury believed an award should be given in accordance with the laws of the United States.