Looking at cracking a WPA/WPA2 handshake predetermined at 8 Characters long only. This means that there are: 208,827,064,576 possible combinations.

Looking at toms hardware page and Rockfish Sec shows you should be able to get over ~42000 H/s per GPU (potentially better).

Assuming you can get up to 8 GPU's per EC2 instance (I could not find out what the maximum is or what the GPU spec is on AWS) you could enable up to 336000 H/s.

With 8 GPUs 208827064576/336000 = 621509 H/s 621509 / 60 = 10358 minutes (duration) 10358 / 60 = 172 hours (duration) 172 / 24 = 7.1 days (duration)

With 1 GPUs 208827064576/42000 = 4972072 H/s 4972072 / 60 = 82867 minutes (duration) 82867 / 60 = 1381 hours (duration) 1381 / 24 = 57 days (duration)

Please check my logic here as I have not done any of this in practice. According to amazon the cost of $0.400/hour for eg1.2xlarge. I am unable to figure out from AWS documentation what the compute power is with EC2 Elastic GPU.

So assuming $0.04/hour *8 (assuming 8 GPU) it would cost $550 or with 1 GPU it would cost $552.

I am looking at review of cost vs GPU/CPU compute power for brute force attacks.

So my question is two part one... can you double check my thinking and two if anyone can clarify the aws/gpu performance vs cost element.

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    AWS has a pricing tool. Questions asking for product recommendations are off topic. As for unit analysis that is outside the scope of discussion here as well. Just make sure all of your units line up and all of your significant figures are good. Oct 2 '17 at 23:59

I believe you have an error. Each password key is not derived by applying a function that is based on a single hash in wp/wpa2 but rather several rounds of PBKDF2 (4096) each resulting to several hash invocations.

Therefore I believe the costs should be higher.

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