1
00:00:00,000 --> 00:00:12,080
In this short lesson, I want to tell you about an amazing utility, NC, which is short for

2
00:00:12,080 --> 00:00:13,680
Netcat.

3
00:00:13,680 --> 00:00:20,280
So NC can be used, they call it the Swiss army knife of networking, by the way.

4
00:00:20,280 --> 00:00:24,000
What I like about NC is that you can use it for quick tests.

5
00:00:24,000 --> 00:00:35,959
So use NC 192.168.29.142.80, for instance, to see if port 80 is currently available.

6
00:00:35,959 --> 00:00:39,439
Connection refused, or 22, well, look at that.

7
00:00:39,439 --> 00:00:47,200
You can see that port 22, we have an answer from an SSH service.

8
00:00:47,200 --> 00:00:55,439
That offers lots of options, and you can use many of them to filter what exactly you want

9
00:00:55,439 --> 00:00:56,439
to do.

10
00:00:56,439 --> 00:01:00,439
It's kind of the polite alternative to the Nmap utility.

11
00:01:00,439 --> 00:01:04,040
You can use protocols, specifiers, and much more.

12
00:01:04,040 --> 00:01:10,360
What I'm using it for is basically to check if certain ports are available, especially

13
00:01:10,360 --> 00:01:15,599
if you are analyzing complex stuff that runs on your network, and you know that someone

14
00:01:15,639 --> 00:01:19,440
in the middle should be answering on port 6443.

15
00:01:19,440 --> 00:01:26,199
Well, use Netcat on port 6443 to check if that is available.

16
00:01:26,199 --> 00:01:31,879
So the basic use, NC followed by the IP address.

17
00:01:31,879 --> 00:01:40,919
So let's check on 146 on port 32175, and oh boy, connection is refused.

18
00:01:41,040 --> 00:01:47,480
So Netcat, my favorite utility if I want to verify that a certain service is offering

19
00:01:47,480 --> 00:01:49,480
its services at a specific port.