How many subnets

[Wozzer]

Hello Guys,

I'm revising for a test I have in a couple of weeks time. One of the questions is:

If the subnet mask is set to 255.255.255.192, How many subnet LANs are possible at this site?

I know the answer is four, but im not sure how you get to it.

Many thanks

 

[oily_17]

Subnet range stretches up to 255, with 0 counting as 1, which means a total of 256.
So you take 256 - 192 = 64 which gives you the amount of addresses each network will contain. Then you take 256 / 64 = 4 which gives you the amount of networks your subnet will have.

 

[Wozzer]

Brilliant - Thanks Hows many computers can you attach each subnet (LAN) ?

 

[HalfAHertz]

Brilliant - Thanks Hows many computers can you attach each subnet (LAN) ?

63?

 

[Easy Rhino]

http://www.subnet-calculator.com/subnet.php?net_class=A

 

[Wozzer]

63?

Duhh of course. My apologises. Wasn't focusing.

 

[oily_17]

63?

Duhh of course. My apologises. Wasn't focusing.

IIRC there are two addresses that are reserved, the first and last in the range.... so therefore you would have 62

EDIT:First number for your router and last number for broadcast address

 

[Praetorian]

Hello Guys,

I'm revising for a test I have in a couple of weeks time. One of the questions is:

If the subnet mask is set to 255.255.255.192, How many subnet LANs are possible at this site?

I know the answer is four, but im not sure how you get to it.

Many thanks

192=11000000 so your net will have 24+2= /26
wildcard (reverse of 192):=00111111=63

for example the network: 192.168.1.0 /26

will have the subnets:

192.168.1.0 ---> 192.168.1.63
192.168.1.64 --> 192.168.1.127
192.168.1.128 -> 192.168.1.191
192.169.1.192 -> 192.168.1.255

so you have 4 subnets;

and 32-26=6 -> 2^6-2=62 available hosts for each subnet!