Reading IP blocks

[Sigmon]

Can somebody tell me how to read an IP block?

for example say it's 4.4.4.128/26

what is that last 26 and what range of IPs does this give me in my block?

 

[nohair]

Hi
The /xx is standard notation for the subnet mask, it tells you how many 1's are in the SNM. For example, a class A SNM has 8 1's, 11111111.00000000.0000000.00000000 and is writeen as /8. So your /26 has 26 1's, so the SNM is decimal reads 255.255.255.192


Using the format 4.4.4.128/26, 4.4.4.128 is your network and you host range is 4.4.4.129 to 4.4.4.190, with 4.4.4.191 being the subnet broadcast address.

Using a /26 subnet gives you 2 legal subnets, and a couple more if you use cisco's ip subnet-zero etc...

-Stephen

 

[Sigmon]

Thanks a lot nohair. Is there anywhere I can find a calc that will do that math for me?

 

[Sigmon]

Found one. Thanks again for the help.