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Questions tagged [networking]

For questions on connecting devices together so that they can communicate with each other, as well as questions on networking equipment such as routers and switches.

Questions on networking are related to how to connect two or more devices such as computers, printers, routers, modems etc. They typically involve networking equipment like routers, switches, etc. Most computer networks are packet-switched, with the most notable implementation being the TCP/IP protocol suite used to implement most of the Internet.

Read more about computer networks on Wikipedia.

See also

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Transatlantic ping faster than sending a pixel to the screen?

John Carmack tweeted, I can send an IP packet to Europe faster than I can send a pixel to the screen. How f’d up is that? And if this weren’t John Carmack, I’d file it under “the interwebs being silly”. But this is John Carmack. How can this be…
Konrad Rudolph
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Did I just get hacked?

I am developing a consumer product, and it is supposed to be connected to the Internet, so as expected, it is connected to the Internet so that I can properly develop it. I went away for an hour or two, and when I came back to my office I noticed…
vaid
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Test if a port on a remote system is reachable (without telnet)

In the old days, we used telnet to see if a port on a remote host was open: telnet hostname port would attempt to connect to any port on any host and give you access to the raw TCP stream. These days, the systems I work on do not have telnet…
Steve HHH
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Ping faster than light

I just discovered very strange thing while testing my internet connection. My ping is smaller than it should be. For example ping time to Arizona State University is about 14ms. eryk@eryk-pc:~$ ping www.asu.edu PING www.asu.edu.cdn.cloudflare.net…
dagi12
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What's the difference between 127.0.0.1 and 0.0.0.0?

I understand that 127.0.0.1 points to localhost, and so does 0.0.0.0 (correct me if I'm wrong). So, what's the difference between 127.0.0.1 and 0.0.0.0?
Sagnik Sarkar
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337
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How to reliably keep an SSH tunnel open?

I use an SSH tunnel from work to go around various idotic firewalls (it's ok with my boss :)). The problem is, after a while the ssh connection usually hangs, and the tunnel is broken. If I could at least monitor the tunnel automatically, I could…
Peltier
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5 answers

What does the "Fi" in "Wi-Fi" mean?

I just got into a heated discussion about Wi-Fi. What does the Fi in Wi-Fi mean? I would have thought potentially "frequency interface" since all network adapters are classified as interfaces. However I'm not certain.
NotAdmin Dave
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How can I list all IPs in the connected network, through Terminal preferably?

Using Ubuntu 10.10 command line, how can I list all IPs connected to my home network? Ideally, it needs to be a CLI command as I will be running it from C++.
Christopher Gwilliams
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259
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Is it possible to ping an address:port?

I am not into networking, and I have the following question related to the Linux ping command. Can I only ping an address? For example: miner@raspberrypi ~ $ ping onofri.org PING onofri.org (67.222.36.105) 56(84) bytes of data. 64 bytes from…
AndreaNobili
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Connect to the host machine from a VirtualBox guest OS?

I'd essentially like to access my host computer from the guest in VirtualBox. Is there an IP address given for my host which I can use from the guest? Are there extra steps required to set this up? I'd like to access my host's Apache, FTP, and SSH…
Naftuli Kay
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225
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14 answers

How do I know what proxy server I'm using?

I need to know what the address for my proxy server is so I can configure another program to also use it. If I go into IE, Internet Properties, LAN Settings, then all I see is an automatic configuration script but not the actual proxy address. How…
Mike Christensen
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What are CLOSE_WAIT and TIME_WAIT states?

When I do netstat -a on my Windows machine, I get a listing of the ports with one of the four states: - LISTENING - CLOSE_WAIT - TIME_WAIT - ESTABLISHED What do CLOSE_WAIT and TIME_WAIT mean/indicate?
Lazer
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scp between two remote hosts from my (third) pc

I have two remote hosts. host1-> 10.3.0.1 host2-> 10.3.0.2 Both run an ssh server. The ssh server listens on port 22 in host1 and on port 6969 in host2. Now, using my local machine, I need to copy something from host1 to host2 without logging into…
uwais ibrahim
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12 answers

Disable "These files might be harmful to your computer" warning?

I keep getting this irritating warning when copying files over the network: These files might be harmful to your computer Your internet security settings suggest that one or more files may be harmful. Do you want to use it anyway? I am copying a…
Jeff Atwood
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13 answers

How can I make the Windows VPN route selective traffic (by destination network)?

I want to use a Windows VPN but only for a particular network, so that it doesn't take over my entire network connection. e.g., Instead of the VPN becoming the default route, make it only the route for 192.168.123.0/24 (I can see that there is a…
Legooolas
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