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SIGINT Reading List

Recent news stories about how NSA and GCHQ operate have brought to light the world of SIGINT: signal intelligence. And many people are surprised that these secret organizations gather so much information looking for 'bad guys'. Putting aside the ethical or political considerations it's worth understanding that what's come to light does not appear to be particularly new. And so the intelligent reader might want to know more about this secret world.

There are a number of books to recommend on the subject.

Spycatcher

Although Spycatcher, Peter Wright's memoir, is mostly about his suspicion that Sir Roger Hollis was a Soviet spy, the book contains quite a bit of detail about electronic eavesdropping. Here's a small part about dealing with The Troubles:
The only major recommendation I made was that we should devise a system of tapping the telephone lines of the Irish Republic. Lines across the border were well covered, but vital Provisional IRA communications flowed back and forth from the west coast of the Republic to Dublin. I devised a scheme for intercepting the microwaves from the attic of the British Embassy in Dublin using a device no larger than a packing case, but although MI5 endorsed the plan, the Foreign Office vetoed it.

The Puzzle PalaceBody Of Secrets, The Shadow Factory

These are James Bamford's books on the history of the NSA and should be read in that order. They give a fascinating insight into the work of the NSA from its beginnings to the present day. Much of what has been recently revealed is talked about in The Shadow Factory or could be inferred from it.

One interesting US operation is Project Shamrock. Bamford writes about this in Body of Secrets:
Many of the intercepts to and from foreign embassies in Washington were acquired as a result of secret agreements between the NSA and the major US telecommunications companies, such as Western Union. Under the NSA program codenamed Shamrock, the companies agreed to illegally hand over to NSA couriers, on a daily basis, copies of all the cables sent to, from and through the US.

GCHQ

Similar in intent to James Bamford's books this covers the British equivalent of NSA, GCHQ, from its beginnings up until very recently. Here's the book discussing the work of GCHQ Bude:
One of GCHQ's largest ventures into the world of vacuuming up telephone calls was launched in Cornwall in 1967. At Goonhilly Downs on the Lizard peninsula there was a satellite receiving station for one of the world's first commercial communications satellites, Intelsat. Displaying a certain amount of barefaced cheek, GCHQ built a duplicate receiving station about sixty miles down the road, near the village of Morwenstow, on the site of a former RAF wartime airfield. Here it could scoop up the same telephone traffic by simply collecting the ‘spillage’ as commercial satellites beamed messages down to earth. This station, with its distinctive domes and satellite dishes littered along the Cornish clifftops, was initially called CSO Morwenstow, and later changed its name to GCHQ Bude. Morwenstow was a classic Anglo-American intelligence venture. NSA paid for most of the infrastructure and the technology, while GCI-IQ contributed the land and paid for the staff and running costs. The massive flow of intelligence it received was shared and processed jointly.
If you read those five books you'd have a good sense of the work of these organizations.

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