Port scanning

After live systems have been identified, it's time to check for any open ports on the target.

So, what is a port? First, let's assume that every host on our network has a unique address assigned to it, known as an IP address. This address is a unique number assigned to a host to differentiate it from other hosts on the network.

Of course, we also need to concern ourselves with when information is sent from system to system and how a computer knows how to accept that information. The answer is ports. I will use the 192.168.1.4 IP address as our target system:

192.168.1.4:80 

So, how many ports are available on a system? There are 65,535 port numbers. Some network services uses TCP ports to ensure their data is delivered to the ...

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