MicroNugget: How to Reverse Engineer an IPv4 Host Address

In this video, Keith Barker covers a three-step process for reverse engineering the subnet address of a host IP address mask. The first is to identify the block size, followed by listing subnets, and finally, seeing where the host fits in that structure.

Keith begins by demonstrating a router interface on a Cisco router, then walks through the three steps necessary for reverse engineering a subnet address of a host IP address mask.

The first step is identifying the block size. To do this, you don’t look at the IP address, but rather the mask itself, which is found at the end of the IP address following a forward slash.

Keith will walk you through how to identify this and then decode what it means. You’ll use this data to list all of the potential subnets, which is the second step.

The third and final step is relatively straightforward: take the data you’ve compiled so far and see where the host fits.

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[KeithBarker]

Thanks Jayram. Your feedback is appreciated!

Best wishes,

Keith

[jamesadams]

Thank you Thank you makes sense to me now!!

[techtutorish]

Oh my dayum, you sure sound positive!

[sulimason]

no audio when I download it..please help