how reverse engineering work?

Question

i work in security engineering position for really sometimes, but there is something amazingly very basic i am still in doubt
we pretty often have our own information system with built in security, we follow the industrial best practices to ensure the security of these propeteriey system, but i have a doubt sin ce the system is private, the hacker would be hard if possible to gain the system, analyse and find vulnerability, but that is practically not easy, and we waste really much on all the info system we developed, so there are the reverse engineering tool that can reveal the original structure of the program they want to hack, including the info for commentation, but what are they and how they do it, can anybody give me a couple of tips or tools

Answer 1

You speak too fast! Put some comas and full stops next time!
The term "Reverse Engineering" refers to exactly what it says:
Start from the finished product towards the drawing board.
The purpose is to avoid the costs of developments and copy (pirate) the product.
Dismantle a watch into its pieces, measure all pieces, make copies, re-assemble more than one watch.
In terms of software, start with the "exe" file, use a disassembler to get a more readable code. Work on this disassembled code to modify the program and remove securities.
In terms of "Chips" with ROMed software, use lab tools to by-pass the locks and read the data in ROM, or open the chip and "read" it with a microscope.
Reverse Engineering is not always efficient: it may cost you more time to "crack" the device than to design your own one.

Answer 2

The program you describe is a "disassembler" which takes computer machine code and reverses it into a higher level "source code" which make it somewhat easier to read. But only in some special cases are the comments saved in the compiled code, so you can not assume you would recover comments. You can use it as a tool to help analyze software, but it hardly does the "reverse engineering" for you, and it would not point out the flaws in a system

Answer 3

The engineer is 70 inches tall. Right now when the hole is 1/3 complete his head is 70 - d/3 inches above ground, where d how deep the hole will be when finished When the hole is finished his head will be twice that far below ground so the hole depth would be d = 70 + 2(70-d/3) and now you can solve for d d = 70 + 140 -2d/3 5d/3 = 210 5d = 630 d = 630/5 = 126 When you first talk to him the hole is 126/3 = 42 inches deep, so his head is 28 inches above ground. When he is finished his head is 126-70 = 56 inches below ground which is twice 28

Answer 4

It depends on what you are reverse engineering.

Consider a Hard disk drive as a black box.
You put signals in, you get data out. From what you put in and what you get out, you determine how it works.

It might be a CD, DVD, or Magnetic Media, or a memory chip inside. It does not matter to you, you only look for the results.