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In this short lesson, I want to tell you about an amazing utility, NC, which is short for

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Netcat.

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So NC can be used, they call it the Swiss army knife of networking, by the way.

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What I like about NC is that you can use it for quick tests.

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So use NC 192.168.29.142.80, for instance, to see if port 80 is currently available.

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Connection refused, or 22, well, look at that.

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You can see that port 22, we have an answer from an SSH service.

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That offers lots of options, and you can use many of them to filter what exactly you want

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to do.

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It's kind of the polite alternative to the Nmap utility.

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You can use protocols, specifiers, and much more.

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What I'm using it for is basically to check if certain ports are available, especially

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if you are analyzing complex stuff that runs on your network, and you know that someone

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in the middle should be answering on port 6443.

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Well, use Netcat on port 6443 to check if that is available.

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So the basic use, NC followed by the IP address.

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So let's check on 146 on port 32175, and oh boy, connection is refused.

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So Netcat, my favorite utility if I want to verify that a certain service is offering

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its services at a specific port.