Black fax

The term black fax refers to a prank fax transmission, consisting of one or more pages entirely filled with a uniform black tone. The sender's intention is generally to use up as much of the recipient's fax ink, toner, or thermal paper as possible, thus costing the recipient money, as well as denying the recipient use of their own machine (similar to computer-based denial of service attacks).[1][2] This is made easier because the fax transmission protocols compress the solid black image very well, so a very short fax call can produce many pages.

Black faxes have been used to harass large institutions or government departments, to retaliate against the senders of junk faxes, or merely as simple pranks.[3][4]

The basic principle of a black fax can be extended to form a black fax attack. In this case, one or more sheets are fed halfway through the sender's fax machine and taped end to end, forming an endless loop that cycles through the machine. Not only can solid black be used, but also images which will repeat endlessly on the receiver's machine until its toner runs out.[5]

The introduction of computer-based facsimile systems (combined with integrated document imaging solutions) at major corporations now means that black faxes are unlikely to cause problems for them. On the other hand, the ability of computer modems to send faxes offers new avenues for abuse. A program could be used to generate hundreds of pages of highly compressed, pure black – or huge volumes of relevant-looking, original, non-repeating high-black-density junk, just as effective but far more difficult to counteract – and send them very quickly to the target fax machine.

Black faxes and fax loops are similar (in both intention and implementation) to lace cards.

See also


  1. ^ Bartlett, Jamie (2014). The Dark Net: Inside the Digital Underworld. Random House. p. 36. ISBN 0434023159. Retrieved 15 June 2017.
  2. ^ Schmundt, Hilmar (February 17, 2011). "Investigators Pursue the Internet Activists of Anonymous". Spiegel Online. Retrieved 15 June 2017.
  3. ^ "Hackers turn to 'low-tech' fax in protesting cybercrime law". GMA News. October 6, 2012. Retrieved 15 June 2017.
  4. ^ Greenberg, Andy (November 30, 2012). "Anonymous Hackers Swat At Syrian Government Websites In Reprisal For Internet Blackout". Forbes. Retrieved 15 June 2017.
  5. ^ Del Gandio, Jason; Nocella II, Anthony (2014). The Terrorization of Dissent: Corporate Repression, Legal Corruption, and the Animal Enterprise Terrorism Act. Lantern Books. ISBN 1590564316.

External links

Denial-of-service attack

In computing, a denial-of-service attack (DoS attack) is a cyber-attack in which the perpetrator seeks to make a machine or network resource unavailable to its intended users by temporarily or indefinitely disrupting services of a host connected to the Internet. Denial of service is typically accomplished by flooding the targeted machine or resource with superfluous requests in an attempt to overload systems and prevent some or all legitimate requests from being fulfilled.In a distributed denial-of-service attack (DDoS attack), the incoming traffic flooding the victim originates from many different sources. This effectively makes it impossible to stop the attack simply by blocking a single source.

A DoS or DDoS attack is analogous to a group of people crowding the entry door of a shop, making it hard for legitimate customers to enter, disrupting trade.

Criminal perpetrators of DoS attacks often target sites or services hosted on high-profile web servers such as banks or credit card payment gateways. Revenge, blackmail and activism can motivate these attacks.


Fax (short for facsimile), sometimes called telecopying or telefax (the latter short for telefacsimile), is the telephonic transmission of scanned printed material (both text and images), normally to a telephone number connected to a printer or other output device. The original document is scanned with a fax machine (or a telecopier), which processes the contents (text or images) as a single fixed graphic image, converting it into a bitmap, and then transmitting it through the telephone system in the form of audio-frequency tones. The receiving fax machine interprets the tones and reconstructs the image, printing a paper copy. Early systems used direct conversions of image darkness to audio tone in a continuous or analog manner. Since the 1980s, most machines modulate the transmitted audio frequencies using a digital representation of the page which is compressed to quickly transmit areas which are all-white or all-black.

Important Records discography

The following is a discography of the American independent record label Important Records and its sublabel Cassauna.

Lace card

A lace card is a punched card with all holes punched (also called a whoopee card, ventilator card, flyswatter card, or IBM doily). They were mainly used as practical jokes to cause unwanted disruption in card readers. Card readers tended to jam when a lace card was inserted, as the resulting card had too little structural strength to avoid buckling inside the mechanism. Card punches could also jam trying to produce cards with all holes punched, owing to power-supply problems. When a lace card was fed through the reader, a card knife or card saw (a flat tool used with punched card readers and card punches) was needed to clear the jam.

List of practical joke topics

A practical joke (also known as a prank, gag, jape or shenanigan) is a mischievous trick or joke played on someone, typically causing the victim to experience embarrassment, perplexity, confusion, or discomfort. Practical jokes differ from confidence tricks or hoaxes in that the victim finds out, or is let in on the joke, rather than being fooled into handing over money or other valuables. Practical jokes or pranks are generally lighthearted, reversible and non-permanent, and aim to make the victim feel foolish or victimised to a degree, but may also involve cruelty and become a form of bullying if performed without appropriate finesse.

Maverick (Hank Williams Jr. album)

Maverick is a studio album by American country music artist Hank Williams Jr. It was released by Curb/Capricorn Records on February 18, 1992. "Hotel Whiskey," "Come On Over to the Country" and "Lyin' Jukebox" were released as singles. The album peaked at number 7 on the Billboard Top Country Albums chart and has been certified Gold by the RIAA.


Telecomix is a decentralized cluster of net activists, committed to the freedom of expression and is a name used by both WeRebuild and Telecomix. WeRebuild is a collaborative project used to propose and discuss laws as well as to collect information about politics and politicians. The Telecomix is the operative body that executes schemes and proposals presented by the WeRebuild. On September 15, 2011, Telecomix diverted all connections to the Syrian web, and redirected internauts to a page with instructions to bypass censorship.Moreover, "Telecomix circulated the ways of using landlines to circumvent state blockages of broadband networks" during the Egyptian Revolution of 2011. Their most recent intervention was a large release of Blue Coat surveillance log files, allegedly revealing vast interception in Syria, which was analyzed and made public from the "telecommunist cluster" of Telecomix. The leak had previously been criticized for possibly revealing too much sensitive information about Syrian users by security researcher and hacker Jacob Appelbaum.

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