ECHELON can actually be tracked all the way beck to World War 2, it is believed to have started up properly in the 1960’s but its origins lie in a agreement signed in 1948 by America and the UK which permitted to two allies to shear signals intelligence in what became known as the UKUSA agreement (this was before the NSA was even founded in 1952).
Anyway without a increasingly boring history lesson (actually its not boring i am just working on another thread right now) at some point in the 1960’s GCHQ and the NSA devised a clever scheme to get around some of the law’s governing eavesdropping on their own citizens and keep tabs of the Soviets. They used their UKUSA agreement to come up with a deal. Essentially they would spy on each other’s citizens; the NSA would spy on us Brit’s and GCHQ on the yanks. Over time this system has got bigger and bigger and its now massive with bases all over the globe. It has massive satellite intercept stations, is tapped into fibre-optic cables and is believed to have intercept stations for radio frequencies in embassies around the world. Its huge and the UKUSA agreement has been expanded now it consists of
GCSB (New Zealand)
Now basically they all work together (please note there is some information that there may be more than these 5 core members), to gather up masses of Signals intelligence and the allegation is that it is then hovered up their massive technological web and fed into the massive super computers at Fort Meade (home of the NSA). So something like 3 times the entire library of Congress is sucked up every hour and fed into these supercomputers. These telecommunications are then scanned for words like “Obama”, “Anthrax” and “Assassinate” and if the supercomputers flag up a communication it is sent so some lonely analyst for further assessment (hello Mr. NSA man).
PRISM is probably just another part of this system, while yes ECHELON it seems was at first just a method to allow SIGINT agencies to circumvent the laws prohibiting them from spying on their own citizens and keeping watch on the Soviets. Now its very possible that its just like one big cyber vacuum cleaner and PRISM is probably just one part feeding into this cyber-espionage web.
How do we know about ECHELON?
Very good question and i am glad you asked
The first evidence of the existence of Echelon came from a freelance journalist named Duncan Campbell in 1988 who wrote the article “Somebody’s Listening” in the New Statesman. In this article he talks about something called “Project 415” in it he states that
Investigators have subpoenaed other witnesses and asked them to provide complete plans and manuals of the ECHELON System and related projects. The plans and blueprints are said to show that targeting of US political figures would not occur by accident, but was designed into the system from the start. While working at Menwith ,Newsham [Duncan’s Source] is reported to have said that she was able to listen through earphones to telephone calls being Monitored at the base.
Other conversations that she heard were in Russian. After leaving Menwith Hill, she continued to have access to full details of Menwith Hill operations from a position as software manager for more than a dozen VAX computers at Menwith which operate the ECHELON system.
This was followed up by a book published by Nicky Hager gave us a very good and brief description of how ECHELON works.
“The ECHELON system is not designed to eavesdrop on a particular individual’s e-mail or fax link. Rather, the system works by indiscriminately intercepting very large quantities of communications and using computers to identify and extract messages of interest from the mass of unwanted ones
This is consistent with most of what is written on ECHELON, while yes it is undoubtedly a massive risk to our civil-liberityes, just like PRISM is, really unless you start a phone call with “OK so we’re bombing Downing Street next Wednesday (hello again Mr. NSA man) you’re going to be ok. I have read that the biggest flaw in ECHELON is the human factor, the computers can only pick out the communications that require further assessment it requires a human to judge if the communication has any value as a intelligence product.
Dr Webb, writing for the encyclopedia of Cyber Warfare and Terrorism wrote that
The ECHELON system is widely accepted to be the most pervasive and powerful electronic intelligence gathering system in the world. It was developed and is operated on behalf of the United States and its partners (the United Kingdom, Australia, Canada and New Zealand) in an intelligence alliance known as UKUSA. The system involves the automatic selection of intercepted electronic messages from target lists using a computer based system known as DICTIONARY. Those messages, which include specific combinations of names, dates, places and subjects, matching particular criteria are sent for further processing by analysts at Fort Mead, Maryland – the Headquarters of the US National Security Agency (NSA). The messages can be intercepted at ground based stations that may link directly into land lines or pick up radio or microwave frequency signals. These signals are broadcast and distributed through radio aerials or a series of microwave towers as part of a local, national or international network. Microwave signals can also be intercepted in space using specially designed satellites positioned to pick up signals which overshoot receivers and continue in a straight line into space. The satellites then downlink the intercepted signals to ground based receivers in a number of geographical locations to enable a global coverage.
The European Union started to get worried, so worried that they commissioned a report into to ECHELON, this report provides lots of very interesting information on ECHELON that i doubt the 5 core members ever wanted to go public (Link to EU Report).