Heh, since I've been set up for it, let's answet the question shall we.
Ok,
IP addressing (version 4, what we use right now) are 32 bit binary addresses used to identigy a host on a network. I must stress this right off the bat, IP addresses are binary numbers. Us humans are overwelmed ny the appearance of this long string of ones and zeros, so we write them in a dotted quad that we all know and love. So heres the deal,
Let's take google's address as an example:
216.239.37.99
Sure. looks normal. However, it is a representation of :
11011000111011110010010101100011
Yeh, not so nice looking eh? Anyways, so here's how it's converted. First we seperate the binary into 4 - 8 bit chucnks like so
11011000.11101111.00100101.01100011
And then convert the binary to decimal. To give a breif overview on how that works, you just keep going up by powers of 2 (like you would powers if 10 in decimail), so each place value goes, 1, 2, 4, 8, 16, 32, 64, and 128 (8 values, 8 bits). so the first octet is
1 1 0 1 1 0 0 0
------------------------------------
128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
------------------------------------
128 + 64 +16 + 8 = 216
Follow? Good.
So now, to answer the original quest, the highest an 8 bit number can be is 255. I'll prove it.
11111111
is
128+64+32+16+8+4+2+1 = 255
so, the range of addresses used is:
0.0.0.0
to
255.255.255.255
both of those having special meanings though, and you can't use em. As well, since they've been brought up, the classes. There are 5 classes of address, and they are decided by what the first couple bits of the address are set to.
Class A - 0...
Class B - 10....
Class C - 110...
Class D - 1110...
Class E - Everything else
SO, to see how this works, we are looking at the first octet of any given ip adress. So for class a, the first bit is always set to zero. So the range of address is
00000000 - 011111111
--------------------
0 - 127
class b:
10000000 - 10111111
-------------------
128 - 191
class c:
11000000 - 11011111
-------------------
192 - 223
class d:
11100000 - 11101111
-------------------
224 - 239
class e: 240 +
Each subnet has it's own default networks,
class a - 255.0.0.0
class b - 255.255.0.0
class c - 255.255.255.0
Class e is used for multicasting only, and does not have a default mask. Class E is expermental only.
If you want to know some more about subnetting try
this on for size. Lemmme know if you have any more questions.
Infinite