Notes on codes, projects and everything
To test our understanding in RSA public key cryptosystem, we were being asked to develop a computer program to demonstrate the cryptosystem. The whole system consists of a random number generator, an encoding module that is able to encode characters into numbers, an encryption module as well as decryption module and finally an RSA cryptosystem cracking module.
The program is written in Microsoft® Visual C6, the reason why Visual C6 is being selected is because we wanted to do something simple. There is no GUI being implemented as we wanted to spend more time in enhancing the program.
To generate random number, we used Blum-Blum-Shub random number generator as we found it to be the easiest to implement.
I happened to find a general solution suggestion on a Wikipedia entry when I was browsing the internet around to find a solution to modular exponential problem. The code snippet posted on the wikipedia entry claimed that it came from …
RSA is a cryptosystem …
Ever wanted to find the number of days between two dates without counting weekend (Saturdays and Sundays)? In PHP you typically needs to do a lot of calculation and a lot of factors needs to be considered. Therefore, in the end you will end up having a whole bunch of code that you will probably start asking yourself whether you are programming a web-calendar or something similar.
The Nand2Tetris part I at coursera is very much my first completed course. It was so fun to actually work through the material and it feels amazing to know how simple it is to actually build a computer from scratch. While it is simple, it doesn’t mean the course itself is easy though. I was struggling to get the CPU wired up properly that I spent two to three days just to get it working.
It is useful to have the terminal around whenever I code. However, while real screen estate is finite, having a terminal further limiting the amount of information that can be displayed at the same time. The problem with the terminal is that I don’t really need it all the time, so I usually find it buried under a group of windows.
As the name implies, Resource Definition Framework, or RDF in short, is a language to represent information about resources in world wide web. Information that can be represented is mostly metadata like title (assuming the resource is a web-page), author, last modified date etc. Besides representing resource that is network-accessible, it can be used to represent things that cannot be accessed through the network, as long as it can be identified using a URI.