CIDR Utilization

Mon Nov 2 18:47:41 UTC 2015

The results appear to be missing 192.168.0.0/32.

Is this intended behavior?

192.168.0.8/27 is not a valid CIDR — It actually represents an address within 192.168.0.0/27, so actually, rather than missing 192.168.0.0/32, one could argue that there are erroneous reports for 192.168.0.2/31, 192.168.0.4/30 being available.

192.168.0.64/26 encompasses 192.168.0.68/32 and 192.168.0.96/29, so there’s also an allocation conflict potential there.

I thought I understood what you were looking for from your question, but your example creates significant confusion.

Owen

> On Oct 30, 2015, at 8:51 PM, John Steve Nash <john.steve.nash at gmail.com> wrote:
> 
> Hi,
> 
> I'm looking for any tool or a way I could specify a CIDR and the prefixes
> that are being used within this CIDR and the tool show me all free
> supernets.
> 
> Example:
> 
> 192.168.0.0/24 - CIDR
> 
> Used subnet's:
> 
> 192.168.0.1/32
> 192.168.0.8/27
> 192.168.0.64/26
> 192.168.0.68/32
> 192.168.0.96/29
> 
> Tool Result => Free Subnet's:
> 
> 192.168.0.2/31
> 192.168.0.4/30
> 192.168.0.32/27
> 192.168.0.128/25
> 
> Regards,
> 
> John