In a previous post, I discussed the analysis of an initially robust-looking combination of S-boxes, then suggested two potential extensions of the algorithm to examine.
Crypto / security | alaric | 
Sun 24th Sep 2006 12:55 am | 
Comments (0)
Today, we went down to Bristol to visit Costco and stock up on baby supplies, and to have an outing in the city centre itself.
It was a lovely place to explore, but I was a bit sad - I remember visiting there about 15 years ago and there being a road with loads of big academic bookshops on near the University; but when we went there today, there was just a single small Blackwells. The others had been replaced with clothes shops, shoe shops, and hairdressers, it seemed.
Still, at the end of the day, we headed back up the M5 with Jean asleep. As we approached junction 11A, I commented that we were nearly home - it was just about ten minutes from there. We took the junction, went along the A417 one junction to the A46, but at Crosshands Roundabout - the exit to continue up the A46 was coned off. "ROAD CLOSED - ACCIDENT".
Alaric, Jean, Sarah | alaric | Sat 23rd Sep 2006 10:49 pm | Comments (1)
Cryptanalysis is the science/art of analysing an encryption system's design to try and figure out how you'd break it.
If encryption systems were used properly, this would be very hard. After all, in that case, all you'd ever have access to was the design of the encryption system and a stream of intercepted encrypted messages.
However, in practice, it's possible to guess parts of the messages (perhaps most start with "Dear ..."), or even to occasionally steal a decrypted message and pair it up with its encrypted version, then study the relationships between them (known plaintext attacks). Or sneak a spy into the organisation being studied, and just ask them to send emails to the person at the other end of the encrypted link, in the middle of the night, at agreed times, so it's easy to spot the encrypted version of the message. Then you have a chosen plaintext attack, which is the most powerful kind.
Crypto / security | alaric | Fri 22nd Sep 2006 1:46 pm | Comments (2)
This evening, we were walking along the drive. It was dark, so I had a headtorch on, and I made a spooky discovery.
You see, the drive is bordered on both sides by farm fields, with a row of bushes and small trees marking the boundary. And the field on one side is full of all-black cows.
The spooky thing is that the cow's eyes light up in a torch beam in the same way cats' do. As in, at the distance away they were, the torch beam didn't light the cows themselves up any more than a faint black sillhouette, but there were several pairs of bright glowing eyes - a disturbing distance apart, leaving no doubt that they belong to something quite larger them myself - peering at us through the hedge.
I'm going to see if I can find a way to get a photo of this rather alarming effect!
Alaric | alaric | Mon 18th Sep 2006 10:22 pm | Comments (1)
I've noticed that some of the best applications I've used (or designed) have been ones with a decent plugin architecture.
In designing applications, I've often noticed that as soon as we add a plugin system, we start to notice that large parts of the app could just be turned into plugins; and if we get time to do this, before long, we have a very simple and generic 'core' with lots of plugins.
This is good, since it tends to reinforce the internal boundaries in the application. It ensures that there aren't any unexpected dependencies between modules.
Computing | alaric | Fri 15th Sep 2006 2:13 pm | Comments (0)
Subscribe