tutorial for converting base 10 numbers to ip addresses

liven

Anyone know where I can get some decent instructions and maybe some practice questions for this?

BeaverC32

I believe you mean convert base 10 to base 2 (or vice versa)...correct? Shouldn't you already know this, being that you have your CCNA?

liven

BeaverC32 wrote:

I believe you mean convert base 10 to base 2 (or vice versa)...correct? Shouldn't you already know this, being that you have your CCNA?

I guess your correct.


However I don't remember having to convert entire IP addresses to base 10 for the CCNA exam. I remember having to do some conversion (base 10 to base 2).

But nothing like:

convert 1110325108

to an dotted decimal IP address or the reverse.

I guess it is one of the exam topics, but most of the stuff I did was converting Hex to decimal to binary, but never an entire ip address.



I guess my question is do you start from the left or the right?


I found a formual:

A standard IP is "base 256." To convert 66.46.55.116 to base 10 the formula is:
66 x (256)3 + 46 x (256)2 + 55 x (256)1 + 116 = 1110325108


And I am pretty certain that this was NOT covered in any of my CCNA studies. Actually I came across this while studying for CEH. This technique is used to obfuscate IP addresses in code.


I have actually started to deal with this at work as well. We write and use software that compares network flows. TO do this we use C code to convert everything to base 10, and then back to dotted decimal, after comaprison is done. Then perl handles generating reports.

But like I said I have never had to do this in my head or by hand, and don't know if I will be able to. Studying for the CEH makes me feel as if it might be necessary.

dynamik

http://www.techexams.net/forums/viewtopic.php?p=11219#11219

[edit]
Sorry, you made it sound like you were just referring a part of subnetting. What you're trying to do is totally different.

liven

I guess I asked the wrong question. I really appriciate everyones response, and wanting to make sure I know how to do what cisco said I needed to do for my test. And I am pretty sure I got that hang of what I need for the CCNA. However I can say I am pretty certain the type of conversion I am talking about here is not a CCNA topic.

I need to be able to convert IP address in dotted decimal format to a regular old number.


I think it is called convert base 10 to IP.

I just don't know if I will be able to do it by hand the math is kinda ruff...


Example.

Convert: 66.46.55.116 to base 10
A standard IP is "base 256." To convert 66.46.55.116 to base 10 the formula is:

66 x (256)3 + 46 x (256)2 + 55 x (256)1 + 116 = 1110325108

Now that was kind of hard, but what about going the opposite direction?

convert:
1110325108

to IP...

Now that seems REALLY hard....

Hopefully there will not be to many questions of that nature..

Netstudent

Unless you are just wanting to crunch numbers, I don't think you would ever need to do that in the real world or for an exam.

liven

dynamik wrote:

http://www.techexams.net/forums/viewtopic.php?p=11219#11219

[edit]
Sorry, you made it sound like you were just referring a part of subnetting. What you're trying to do is totally different.

Hey thanks for the link, it helped me realize I am only partially crazy.

liven

Netstudent wrote:

Unless you are just wanting to crunch numbers, I don't think you would ever need to do that in the real world or for an exam.

I really hope you are correct.

I have come across this topic while studying for the CEH, just don't know how far they are going to take it...