IP Wildcard Mask Address Objects

[SARowe_NZ]

Hey,

This properly confuses me every time I look at it. Is anyone able to explain in very simple terms how to work out what the mask should be?

For example: We have an IP scheme that looks like 10.x.128.0/24 where the x changes for each site. We have been using an IP Wildcard address object of 10.128.128.0/0.127.127.255 which seems to have been working for sites 10.[128-201].128.0/24 but now we have a site that uses 10.224.128.0/24 and the wildcard address object does not seem to match it.

What is our address object of 10.128.128.0/0.127.127.255 actually covering?

How can I understand easily how to work out what a mask should be?

Thanks!

Shannon

[Elwin3]

Hi, that’s a great thread.
Wildcard masks can get confusing fast. The mask 0.127.127.255 doesn’t cover everything from 10.128.0.0 upward because the third octet isn’t fully open. You could simplify it with 0.127.255.255 to include all networks between 10.128.0.0 and 10.255.255.255 or split it into multiple objects if you need tighter control.

https://www.calculator.net/ip-subnet-calculator.html
https://pingmynetwork.com/network/ccna-200-301/what-is-subnetting