Pity the article has no technical content and fails to mention the portable secure speech system Delilah that Turing worked on: https://blog.jgc.org/2012/03/delilah-secure-speech-system.ht...
How Margaret Thatcher's Brahms phone was invented
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Re: How Margaret Thatcher's Brahms phone was invented
#12Story has not so much as a single word about how it was invented.
Yes, disappointing on technical content.
AFAIK digital speech codecs were a thing in 1980, and implementing a symmetrical block cipher on 2.4KHz would have been possible using discrete logic or a processor like the Z80.
Up to that point a different system was used, called a "scrambler". Speech was fed into a vocoder (parallel filter bank). The energy in each band would be used to resynthesise the speech using a reverse vocoder (noise/oscillator bank). In a scrambler the bands are shuffled before sending, and unshuffled at the other end.
The result is speech-like, but incomprehensible.
In terms of security this is no more complex than a simple transposition cipher. An adversary would have to record the conversation and then set about trying every band transposition. In practice you'd only have to get a few right for the speech to become intelligible once again, so the value was really to stop real time snooping and slow down an eavesdropper.
The BBC article fails to communicate how the move to a digitised block cipher offered considerable security advantages over the incumbent systems.
Re: How Margaret Thatcher's Brahms phone was invented
#13Earlier quoted context omitted.
That's because it is (subtle) propaganda, designed to elicit feelings rather than deliver facts. Self-actualization, it suggests, requires external endorsement. "We knew that every piece of information we were sending out to our chaps was significant," she says, recalling watching the importance of their work reflected back on the TV news.
I was a kid at primary school when the Falklands war was underway, I remember how the teachers were telling us Argentina was bad for invading and we should support the armed forces. We had to draw pictures of the Falklands conflict from images we might see in the papers, because I was made to draw silhouettes of the Navy boats! Even at Primary School here in the UK, kids were being propagandised and I bet it still go…
Any chance of evidence for the text that starts "but it also extends ..." ?
Just anything to support the concept that tens of thousands of individuals of myriad types and interests are acting in a concerted manner to intimidate and harass the rest of the population will do.
Re: How Margaret Thatcher's Brahms phone was invented
#14Story has not so much as a single word about how it was invented.
That's because it is (subtle) propaganda, designed to elicit feelings rather than deliver facts. Self-actualization, it suggests, requires external endorsement. "We knew that every piece of information we were sending out to our chaps was significant," she says, recalling watching the importance of their work reflected back on the TV news.
By this meaning of propaganda, likewise, so is your comment.
It's designed to elicit feelings rather than facts. State discussion of its technologies is suspicious, this comment says.
Re: How Margaret Thatcher's Brahms phone was invented
#15Maybe it's because I grew up in the 1980s and so they seem more recent, but the idea that government communications security depended on a piece of paper tape sounds positively antique.
Re: How Margaret Thatcher's Brahms phone was invented
#16Pity the article has no technical content and fails to mention the portable secure speech system Delilah that Turing worked on: https://blog.jgc.org/2012/03/delilah-secure-speech-system.ht...
That system also makes a cameo in Neal Stephenson's Cryptonomicon:
https://tentacle.net/~chrisr/bookshelf/Stephenson,%20Neal%20...
Can't vouch for what he wrote of course but he probably got a lot of the details right.
Re: How Margaret Thatcher's Brahms phone was invented
#17Earlier quoted context omitted.
I was a kid at primary school when the Falklands war was underway, I remember how the teachers were telling us Argentina was bad for invading and we should support the armed forces. We had to draw pictures of the Falklands conflict from images we might see in the papers, because I was made to draw silhouettes of the Navy boats! Even at Primary School here in the UK, kids were being propagandised and I bet it still go…
Argentina was bad though? If ever there was a just war, it was this.
Without in any way endorsing Argentina, you might like to reflect on why Britain (qua state) cares so much about the Falklands. Hint: it's not out of tender feeling for a small number of sheep farmers.
https://en.wikipedia.org/wiki/British_Antarctic_Territory
Re: How Margaret Thatcher's Brahms phone was invented
#18Earlier quoted context omitted.
I was a kid at primary school when the Falklands war was underway, I remember how the teachers were telling us Argentina was bad for invading and we should support the armed forces. We had to draw pictures of the Falklands conflict from images we might see in the papers, because I was made to draw silhouettes of the Navy boats! Even at Primary School here in the UK, kids were being propagandised and I bet it still go…
Any chance of evidence for the text that starts "but it also extends ..." ? Just anything to support the concept that tens of thousands of individuals of myriad types and interests are acting in a concerted manner to intimidate and harass the rest of the population will do.
I'm in no way able to provide evidence because its very clever and full spectrum you dont realise what people are getting at the time. I've got wise to some of it now, but you need to understand how the innuendo game plays. If you dont get innuendo, you wont get it, but its extremely clever and is something that is played out over decades. However I will leave you with this thought, if you recognise the existence of preemptive military attacks then it could be argued that the military dont accept the British legal stance of "innocent until proven guilty". Ergo anyone backing the military, backs state sanctioned illegal activity which is why the security/secret services exist!
Re: How Margaret Thatcher's Brahms phone was invented
#19Earlier quoted context omitted.
I was a kid at primary school when the Falklands war was underway, I remember how the teachers were telling us Argentina was bad for invading and we should support the armed forces. We had to draw pictures of the Falklands conflict from images we might see in the papers, because I was made to draw silhouettes of the Navy boats! Even at Primary School here in the UK, kids were being propagandised and I bet it still go…
Argentina was bad though? If ever there was a just war, it was this.
Well have far back in time does one go to settle a dispute? I think Isreal's existence claim goes back to the time of Christ, Roman & Egyptian times, so is that the precedence we should adopt globally because we know how many clever Jewish scholars there are and they wouldn't be wrong would they?
However my point is, with hindsight I object to the propaganda and one sided nature of the clearly biased teaching I was subjected to at the time, possibly even without parental consent because its not like many parents even get a say in what their kids are taught. The knock on effect is now starting to play out, decades later!
Re: How Margaret Thatcher's Brahms phone was invented
#20Earlier quoted context omitted.
Argentina was bad though? If ever there was a just war, it was this.
Well have far back in time does one go to settle a dispute? I think Isreal's existence claim goes back to the time of Christ, Roman & Egyptian times, so is that the precedence we should adopt globally because we know how many clever Jewish scholars there are and they wouldn't be wrong would they? However my point is, with hindsight I object to the propaganda and one sided nature of the clearly biased teaching I was s…
How would you have expected the state broadcaster to behave? This was the usual behaviour up until the Falklands (and I was in Junior school in the UK as well at the time).
More recently, the BBC seems to prefer to talk down their home country armed forces.