121–130 of 144 posts
I forget who told me this story, but at some point the British tried a crazy known-plaintext attack by planting handwritten notes in dead German soldiers’ pockets that contained an “important message” to be sent, and then in the following days they would attempt to decrypt enigma communications against the known plaintext.
You can listen to the podcast, if you want. It's called operation Mincemeat https://pca.st/podcast/0d412ec0-af39-0139-c19f-0acc26574db2
I forget who told me this story, but at some point the British tried a crazy known-plaintext attack by planting handwritten notes in dead German soldiers’ pockets that contained an “important message” to be sent, and then in the following days they would attempt to decrypt enigma communications against the known plaintext.
Lots of interesting stories in there, including when he suspected that Germans had captured all of their Dutch spies and were transmitting fake messages: real agents made mistakes when encoding due to stress, the Germans' fake encodings were all perfect.
Earlier quoted context omitted.
"Colossus was not a computer. It was a key-tester," The original definition of computer was basically a person wot computes (analyzes data and performs arithmetic and so on). That would have mostly involved pencil and paper, fag packets and napkins. IT co-opted the term for their devices, many years later. What is your issue with Colossus performing automated computations/analysis given some inputs of some sort and h…
I think the gp was confused with other devices. Colossus was indeed a computer by most definitions. I think the poster winced it up with the Bombe or other systems - not surprising because colossus wasn’t really known for many years. (It was secret into the 1970s iirc) Other devices would calculate but not store instructions. The common ones you see are the fire directors on naval ships, which were analog “computers”…
There were many early machines which checked some, but not all, of those boxes. IBM's electronic multiplier. The Harvard Mark I. The SSEC. Colossus. Reservisor. Western Electric Plan 55-A. General Railway Signal's NX. The Bell Labs Complex Calculator. The Automatic Odds option for racetrack totalizators. The Mathatron. All of those machines did something that resembled computation.
The late 1940s, 1950s, and 1960s were full of strange special-purpose electronic digital hardware that didn't quite make it to a computer, because the parts count to get to a general purpose machine was too high.
Then came microprocessors, and it became cheaper to use general purpose microprocessors in dedicated applications. Now all those weird machines are forgotten.
Here's a brochure from Teleregister, which built custom special purpose systems for railroads, the military, airlines, stock exchanges, and such, from before WWII into the 1960s. There's no computer in those things, but a lot of electronics.
Earlier quoted context omitted.
Or ending it with the same salute involving the name of the leader, for that matter.
Isn't that why we have PFS now?
LLMs would be amazing for this
Earlier quoted context omitted.
You can listen to the podcast, if you want. It's called operation Mincemeat https://pca.st/podcast/0d412ec0-af39-0139-c19f-0acc26574db2
Now also a quite good West End musical
Earlier quoted context omitted.
I think the gp was confused with other devices. Colossus was indeed a computer by most definitions. I think the poster winced it up with the Bombe or other systems - not surprising because colossus wasn’t really known for many years. (It was secret into the 1970s iirc) Other devices would calculate but not store instructions. The common ones you see are the fire directors on naval ships, which were analog “computers”…
By "computer" I mean what we call a computer today - a stored program general purpose electronic digital computer. There were many early machines which checked some, but not all, of those boxes. IBM's electronic multiplier. The Harvard Mark I. The SSEC. Colossus. Reservisor. Western Electric Plan 55-A. General Railway Signal's NX. The Bell Labs Complex Calculator. The Automatic Odds option for racetrack totalizators.…
Mark I was an electro-mechanical computer, while SSEC was hybrid, including both electro-mechanical parts and parts with vacuum tubes. For a few years, IBM's SSEC was the world's most powerful "supercomputer", and it has solved a great number of diverse problems. SSEC had some advanced features that have been introduced in fully electronic computers only about a decade later, e.g. pipelined instruction execution (to compensate for its slow circuits).
What you mean is that none of your examples was a von Neumann computer, i.e. where there is a common memory for program storage and data storage, enabling the computer to create or modify programs by itself.
Obviously the common memory was an essential element for the evolution of electronic computers, enabling many features that were impossible when the programs were stored separately, on a ROM such as punched tape.
However, saying just "stored program" also covers the case when the program is stored in a separate ROM, as it may still be the case for a microcontroller, though nowadays most of them store the program in an alterable flash memory.
Earlier quoted context omitted.
This is the first I’ve heard of Colossus influencing the ENIAC. I was under the impression that Colossus was so secret that ENIAC was designed independently and (falsely) touted as the first tube computer prior to Colossus’ existence being declassified. I’m not sure if I’m misremembering that though.
The ENIAC seems to be the first general purpose electronic digital computer. It wasn't stored program, though - no good memory devices. Plugboards and lots of rotary switches. Took hours to load a new program. Unrelated to Colossus. The first machine to have it all was the Manchester Baby.[1] Now this really was sort of a descendant of Colossus, with some of the same people involved. It was mostly a test rig for the…
With ENIAC, reconfiguring the computer for solving a new problem was done essentially in the same way as for an analog computer (or nowadays for an FPGA), by rewiring the connections between the arithmetic units, the storage registers and the control sequencers, so that ENIAC will solve the new problem when powered on.
The resemblance of ENIAC to an analog computer is not an accident, but its architecture has been conceived as an electronic substitute of the electro-mechanical analog computers known as "differential analyzers", which had been in widespread use both before WWII and during WWII, for computing solutions of systems of differential equations, which were found in various engineering problems, including in many of military importance.
On the other hand, Harvard Mark I had been inspired by Babbage's proposal for a digital computer with stored program, hence its architecture much closer to modern digital computers.
While ENIAC had an architecture inspired by the mechanical differential analyzers, for the schematics of its electronic arithmetic and register circuits it used some information from the designers of the earlier Atanasoff-Berry Computer, which was a special-purpose electronic computer for solving systems of linear algebraic equations, and which included even the first DRAM memory (the second DRAM memory will be the British Williams CRT).
I forget who told me this story, but at some point the British tried a crazy known-plaintext attack by planting handwritten notes in dead German soldiers’ pockets that contained an “important message” to be sent, and then in the following days they would attempt to decrypt enigma communications against the known plaintext.
You can listen to the podcast, if you want. It's called operation Mincemeat https://pca.st/podcast/0d412ec0-af39-0139-c19f-0acc26574db2