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Peeking from behind net curtains, or through a keyhole, listening to neighbours through a wall – such images smack of silent movies and murder mysteries. However, we are all guilty of eavesdropping. Curious by nature, we listen in on conversations in cafés, on public transport, in the office. We can’t help ourselves, we like to know what’s going on in people’s lives, it’s interesting, it’s fascinating, and mostly harmless.

Historical and literary accounts of eavesdropping and espionage go back as far as ancient civilization, 6000 years ago. Egyptian hieroglyphics reveal the presence of court spies. The Trojan Horse, a tale of Ancient Greek subterfuge is described in length in Virgil’s Aeneid. Rome’s most famous case of espionage resulted in the assassination of Julius Caesar in 44 BC.

Eavesdropping in England during the Middle Ages was a punishable offence, not, according to records, to protect people’s right to privacy, but because eavesdropping was “damaging to local harmony, goodwill, and peaceful relations between neighbours.” (Ref. 1)

eavesdrop /'i:vzdrɒp/Origin: Early 17th century: back formation from eavesdropper (late Middle English) ‘a person who listens from under the eaves’, from the obsolete noun eavesdrop ‘the ground on to which water drips from the eaves’, probably from Old Norse upsardropi, from ups ‘eaves’ + dropi ‘a drop’. 

Source: Oxford Dictionary, Oxford University Press


The rise of domestic surveillance

The origins of global surveillance can be traced to the late 1940s when the UK and US governments entered into the UKUSA Agreement, that culminated in the creation of a global surveillance network, code-named ECHELON. Created to monitor military and diplomatic communications of the Soviet Union and the Eastern Bloc during the Cold War of the 1960s, the system could, by the late 1990s, intercept satellite transmissions, PSTN communications, and even transmissions carried by microwave. ECHELON’s existence was denied by both Britain and the US, but a report by the European Parliament in 2001 confirmed the programme’s existence, warning Europeans that this was “a global system for the interception of private and commercial communications.” (Ref. 2) No longer a military or political act, surveillance was intruding into our private matters.

knowledge, resource center, articles, eavesdropping origin

The telegraph revolutionized espionage operations. Using the dots and dashes of Samuel Morse’s code, governments started sending messages over telegraph wires, and it wasn’t long before rival intelligence services learnt how to listen to the messages by tapping the lines. Source: ”The Boy Spy” by Major J. O. Kerbey.

Domestic surveillance escalated significantly in the 2000s. In Britain, ‘an organized trade in confidential personal information’ (Ref. 3) had developed and was widely used by the British press. Unscrupulous and cynical journalists gathered information by every means possible from hacking private voicemail accounts and computers to entrapment, blackmail and theft of mobile phones. 

The public’s awareness of domestic surveillance heightened with the unravelling of the News International phone-hacking scandal involving News of the World and other newspapers published by News International, a subsidiary of News Corporation. Employees were accused of phone hacking, police bribery, and exercising improper influence in the pursuit of stories on celebrities, politicians, and members of the British Royal Family. However, the revelation that the phones of a murdered schoolgirl, the relatives of deceased British soldiers, and victims of the 7 July 2005 London bombings had also been hacked caused public outcry, leading to several high-profile resignations, including that of Rupert Murdoch as News Corporation director. 

In 2013, computer programmer, and former subcontractor for the NSA, Edward Snowden, made headlines when he handed over 200,000 top-secret documents to various media outlets, many of them detailing the monitoring of American citizens. The leaks reinforced the enormity of domestic surveillance proving that regardless of who you are, details of purchases you make by credit card, websites you visit, emails you send, hotels you book and events you attend are stored in some massive database somewhere to be searched through and assessed.

When Snowden’s identity was revealed at his request, he said, “I do not want to live in a world where everything I do or say is recorded.” And if we ignore the hero/traitor controversy that surrounds his person, who can disagree?

Hacked off

A customer concerned with mobile phone security contacted Brüel & Kjær for help in designing a device to prevent hackers from eavesdropping on conversations by misusing mobile phones.

The resulting box provides high attenuation of sound thanks to its optimized construction. To augment the sound attenuation, and ensure further enhanced security, random noise is produced inside the box once it is closed and activated. The noise is inaudible outside the box but masks even the loudest of conversations from the phones inside. Green indicator lights on the front of the box show when it is safe to talk. While there might be other ways to enhance the security of discussions, such as RF shielding or turning the phone off, the true benefit of the box is that it doesn’t prevent the phone owner from receiving messages or calls. An event on any of the phones in the box is detected and a blue light indicates an incoming message or call. The meeting attendees can then decide whether to pause discussions, open the box and take the call or ignore it.  


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