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I see many connections like when I use netstat, are they all to the internet? Are there any connections to the internet or other things that aren't forthcoming?

I guess what I'm asking is what does "AC adapter is online" actually mean, and do I have to have a WiFi adapter to connect to the "cloud" or is there something built in that does that without my permission?

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I think you will see the ip 127.0.0.1 a lot. That belongs to the local loopback device. The X-server talks with clients (on the same machine) over that ip. So, there is no internet traffic for that purpose. –  Tobias Aug 29 at 12:44
    
@Tobias: If DISPLAY is set to localhost:0, then X talks over 127.0.0.1. It's my understanding that, if DISPLAY is :0, the intra-machine communication is implementation-dependent, and could (for example) be FIFOs or message queues. –  G-Man Aug 29 at 13:58
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@G-Man "The communications channel between an X client and server is full-duplex: either side can send a message to the other at any time. This is canonically implemented over a TCP/IP socket interface, though other communications channels are often used, including Unix domain sockets, named pipes and shared memory." Cited from x.org/wiki/guide/communication. –  Tobias Aug 29 at 15:56

3 Answers 3

Q#1: I see many connections like when I use netstat, are they all to the internet?

No not all connections listed in the output of netstat are to the internet. Many of these so-called connections are to files that are in use on your system. These are special files, one of which, is called a socket.

A socket file allows an application to "talk" to another program. You can see a sampling of these files with this command:

$ netstat -an  | grep -i sock | head
Active UNIX domain sockets (servers and established)
unix  2      [ ACC ]     STREAM     LISTENING     22576    /var/run/abrt/abrt.socket
unix  2      [ ACC ]     STREAM     LISTENING     2485307  /tmp/.esd-1000/socket
unix  2      [ ACC ]     STREAM     LISTENING     617      /run/lvm/lvmetad.socket
unix  2      [ ACC ]     STREAM     LISTENING     1182015  /var/run/docker.sock
unix  2      [ ACC ]     STREAM     LISTENING     2443437  /tmp/zim-slm/zim-server-socket
unix  9      [ ]         DGRAM                    10175    /run/systemd/journal/socket
unix  2      [ ACC ]     STREAM     LISTENING     2485206  /tmp/.com.google.Chrome.1bDRUM/SingletonSocket
unix  2      [ ACC ]     STREAM     LISTENING     18139    /var/run/cups/cups.sock
unix  2      [ ACC ]     STREAM     LISTENING     19685    /var/run/dbus/system_bus_socket

Q2: Are there any connections to the internet or other things that aren't forthcoming?

All connections are forthcoming in the sense that they'll show up in netstat's output, if they're currently active. An application that is malware will often times include a modified version of tools such as netstat which has been modified to mask the malware from being displayed when run.

Q#3: I guess what i'm asking is what does "AC adapter is online" actually mean...

The AC Adapter being online has nothing to do with the term being "online" on the internet. This simply means that he charger for your PC is connected and charging your battery.

Q#4: ... and do I have to have a WiFi adapter to connect to the "cloud" or is there something built in that does that without my permission?

You do have to have either a WiFi adapter or Ethernet adapter or some sort of "modem" device that will connect you to a system that's connected to the internet.

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re: netstat, A note on "if they're currently active". UDP can send packets in an instant with no assumption of receipt or creation of a session, this makes it very easy for it to slip past checks using netstat. If you want to monitor your communications, you need to use a sniffer or configure firewall rules to report your traffic. An external firewall being preferred if you don't trust the system being monitored. –  mgjk Aug 29 at 13:47

i see many connections like when I use netstat, are they all to the internet?

That depends on the output, you have to tell IPv6 and IPv4 apart. In IPv4, the following adresses are so-called private:
10.x.x.x
172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255

and are there any connections to the internet or other things that aren't forthcoming?

netstat lists all open connections, so the answer is no.

I guess what i'm asking is what does "AC adapt4r is online" actually mean?

Did you mistype that? An "AC adaptor" is the thing that plugs into a wall outlet and powers your computer. "AC adapter is online" means that your computer is currently on AC power (as opposed to battery power).

and do I have to have a wifi adapter to connect to the "cloud" or is there something builgt in that does that without my permission?

The "cloud" is usually used as a modern-day buzzword for what the elders call "server" (I know I'm generalizing). That server (or cloud, if you wish) can be either "on premise", that is in your home or company, or it can be "in the internet". Either way, your computer can only connect to other computers through network interfaces like wifi and ethernet. The cloud is not something that is built into the hardware.

If you have a network connection and do not trust your computer, then you need to learn about networking, routing and firewalls to stop your machine(s) from making potentially unwanted connections.

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Of course, strictly speaking, if the machine is infected with a rootkit, selected malicious connections might not be displayed by netstat. But that's a bit out of the scope of the question. –  G-Man Aug 29 at 13:55
    
Correct, but it would have been an even longer answer. –  Jan Aug 29 at 13:58

I see many connections like when I use netstat, are they all to the Internet?

It depends on how you define “the Internet”. If you’re at home, and you have multiple computers, some of the connections might be to your other computers.  If you’re at work, it’s highly likely that you have connections to other machines at work.

Are there network connections that don’t use the Wi-Fi card or the Ethernet port?

Can there be network connections that don’t use the Wi-Fi card or the Ethernet port?

In principle, certainly.  Back when dinosaurs roamed the earth, personal computers generally didn’t have Wi-Fi cards or Ethernet ports.  They used a serial port to talk to a modem, which talked to the ISP through the phone lines.

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