If you understand Subnetting, then you probably know that the CIDR notation of /24
correlates to the Subnet Mask of 255.255.255.0
. But did you also know both of those correlate to the Wildcard Mask of 0.0.0.255
?
This video picks apart Wildard Masks, what they are, and how they are used. We’ll cover the following concepts:
- Basic Definition of Wildcard Masks
- Binary Conversions (CIDR to Subnet to Wildcard)
- Special Wildcard Masks: /32 and /0
- Easier Conversions between Subnet Masks and Wildcard Masks
- What can you do with a Wildcard Mask?
- Determine if two IP addresses are in the same Subnet
- Identify IP addresses in a particular Subnet
- How is a Wildcard Mask different from a Subnet Mask?
- Discontiguous Wildcard Masks
This video is a follow up to a video I released earlier in the month discussing Binary. Both this video on Wildcard Masks, and the aforementioned Binary videos are pre-cursors to a video on Access Control Lists (ACLs) that I am working on.