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So starting next week, running for a week, I plan on scanning for ports 0-65535 (TCP). Each probe will be completely random selection of IP+port. The purpose is to answer the question about the most common open ports.
This would take a couple years to scan for all ports, so I'm not going to do that. But, scanning for a week should give me a good statistical sampling of 1% of the total possible combinations.
Specifically, the scan will open a connection and wait a few seconds for a banner. Protocols like FTP, SSH, and VNC reply first with data, before you send requests. Doing this should find such things lurking at odd ports. We know that port 22 is the most common for SSH, but what is the second most common?
Then, if I get no banner in response, I'll send an SSL "Hello" message. We know that port 443 is the most common SSL port, but what is the second most common?
In other words, by waiting for SSH, then sending SSL, I'll find SSH even it's on the (wrong) port of 443, and I'll find SSL even if it's on port 22. And all other ports, too.
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