In der Vorlesung vom 25.04.2013 hat Prof. Hofheinz gesagt, dass man semantische Sicherheit praktisch nicht beweisen kann, da man zuerst beweisen müsste. Warum das so ist, versuche ich nun zu erläutern. Einwegfunktionen und Sei eine Funktion. heißt eine Einwegfunktion, genau dann wenn für alle gilt: kann in Polynomialzeit berechnet werden Für die Berechnung eines Urbildes [...]
RWX Files Linux files have three important access rights for files: Read Write Execute If you want to mark a file as executable, you can add the x-right: When you want to mark a file as readable, you can dd the r-right: You can remove rights in a similar way: Now, often this is expressed [...]
The following clip is a nice, short explanation of Stuxnet, a computer worm discovered in June 2010:
Today I’ve changed my PayPal password, because I thought it was time to do so. Now I know that the password changing service of PayPal can be improved quite a lot. I had to type the password about twelve times! This is the reason why I thought it was time to create some principles for [...]
Challenge websites are websites which offer many tasks to solve and a ranking system. If you solve the challenges, you get points and your rank increases. You don’t get anything else. No money, no price. Only the knowledge and the ranking. Which is enough in my opinion. It might sound strange to others, but its [...]
