Back in Roorkee I was occasionaly asked this question: How to be a hacker ? Not that I am a hacker myself... neither I ever claim to be one. To be frank according to the widely popular definition of hacker, I am most certainly not one. Not to digress further, I encountered a howto once on becoming a hacker.
In my very own definition a hacker is a person who has got a really good knowledge of a certain or a class of systems. A hacker can hack a radio, a spectrum , a software or even a car engine. More importantly he cannot be the one who designed the system but has a keen interest in it. To hack is to exploit the system to make it do what you want it to do but was possibly not an intended application. Like you can hack a PSP to play it like drums (somebody has actually done it!!).
So how is system design and a hacker's perspective related ? There can be at least two types of system designs in relation to a hacker's perspective. One that keeps into mind that there will be people who will try to tinker with the original system and try to expand it. The other types of systems are those which are strict about their rules and will not allow anyone to exploit them for any other use.
Let us consider the latter case of the two and divide a hacking problem in two parts. One the component to be hacked and other the platform on which it needs to be hacked. A hacker keenly studies the design of both the systems, typically a top layer and a bottom layer, the top is where the hack needs to be performed and the bottom layer is on which the hack will be done. An analysis of behaviour of both these systems is required. One needs to know both the strong and weak points of these layers and needs to put them together and tweak wherever possible to get the desired output.
Therefore from the hacker's perspective a system can be manipulated if it is layered and each layer there is a possibility to do some sort of analysis and somehow effect the behaviour of system at that layer.
