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xedios 10-22-2004 07:14 AM

Dumb question
 
can you hellp me out from this ..


I realy don't know what this means if you specify
network addres like this 192.168.1.0/16
or sopmething like this

I realy don't know.

Thanx

Black_iCE_mdk 10-22-2004 07:22 AM

192.168.1.0 = ip of machine on ....

(192.168.1.0)&(255.255.0.0)= network 192.168.x.x

so basically the ip address is a 32 bit number and the subnet mask can be a 32 bit number. By preforming an AND operation you determin the network range, or atleast the range that the packet can travel from the work station.

noticed that i said 255.255.0.0 that is the same in binary as 11111111 11111111 00000000 00000000 b which can be written in shorthand as 16 consequative ones... ie /16.

xedios 10-22-2004 07:25 AM

If i get it corectly


192.168.1.0/16
it is teh sam like

192.168.1.0 thru 192.168.254.254 ?

I am alitle bit confused abaut this

what if in the en you hava an 18 ?? or semething else

I konw it its a very doumb question.

acid_kewpie 10-22-2004 07:43 AM

not a dumb question, but a dumb title if i may say so. please try to use more informative titels in the future.

possibly the easiest way to get to grips with this mask notation is to draw both addresses out in binary, and basically add them together. when you're dealing in a decimal base it's hard to understand where the seemingly arbitrary subnet blocks come from.

xedios 10-22-2004 07:49 AM

Ok

I am still stuck .

can you provide me whit som tust explanations or web pages ..
whitch are pointed in this direction

thanx for the replay

Black_iCE_mdk 10-22-2004 07:51 AM

Quote:

192.168.1.0 thru 192.168.254.254 ?
Ok, another analigy.....
right; lets say my name is John Smith and your name is Mike Smith. So in computer terms is would be like saying

"John Smith"=192.168.10.1/255.255.255.0 and "Mike Smith"=192.168.10.2/255.255.255.0

and when we talk i say "Mike - have you gone to the beach" and you reply "Yes John, you should have seen those chick there." Notice that we don't say Smith to each other. This is silent as we both are Smiths we don't need to know the last name.

Ok now Mike Lubba walks into the room { and in computer terms he could be 192.168.20.5/255.255.0.0 }
and now he says "John how are you". Well now if i say "I am fine Mike" then who am i saying this to ? Smith or Luke? So i'll say "I am fine Mike Lubba". And as you notice saying last names the whole time gets tiring - and writing them even whorse so i'll just say Mike S and Mike L.

So we write 192.168.1.0/16 as a shorthand for 255.255.0.0 as i said Mike L

xedios 10-22-2004 08:00 AM

Ok nice explanation

I made agen a mistake I asket the wrong thing. I met

How I calculate the /numbers

14 = ??
16 = 255.255.0.0
18 = ??

Here sits my problem.

I understend the subnet mask, I only don't understand the ending code 192.168.0.1/ xx ( colud be 14 16 18 or sonmethin else )

if you have some mor will to ansver me please do

Thanx

acid_kewpie 10-22-2004 08:07 AM

14 = 11111111 11111100 0000000 00000000 = 255.(255-4).0.0 = 255.251.0.0

18 = 11111111 11111111 1100000 00000000 = 255.255.(128+64).0 = 255.255.192.0

unless my math is wrong.... which happens. a lot.

xedios 10-22-2004 08:11 AM

OK

A litle mor clear , But I still don't know haw You did the calculation..

no mether

..

if you have time and a lot of will, then you can explain to me

Thanx

Black_iCE_mdk 10-22-2004 08:12 AM

PC's in general (IBM compatile machines) have come to know standards so that a form of consistency can exist on many systems.
One of these is the number of binary digits will make up an significant peace of information. The number was decided to be 8 bits of length. so now we can do this the old way to illustrate this.

Decimal:Binary
0 00000000
1 00000001
2 00000010
3 00000011
4 00000100
.... .......
[skip a few]
.... .......
255 11111111

and this is where we have the range of 0 to 255 occuring. In IP addresses they will ALWAYS be multipals of 8 ie /8 /16 /24 /32 [stop], and they will only be those numbers. so look @ it again:

"underlined to show what will be taken"

192.168.1.0/8
___
192.168.1.0/16
______
192.168.1.0/24
________
192.168.1.0/32
__________

and that is it.

xedios 10-22-2004 08:23 AM

Thanx

Veeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeery much !! :D :D


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