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What happens if I am connected to my neighbor’s wireless and my USB modem at the same time?


Leo, my neighbor sometimes lets me use his WiFi. My laptop is supposed to
automatically connect to his wireless network, but I sometimes need some privacy
and connect to the internet through my own private USB modem. Can he still
monitor my internet traffic even though I’m using my own USB, which is supposed
to be authenticated? And can he monitor my traffic if my laptop is connected to
both at the same time?

In this excerpt from
Answercast #12
, I look at configuring multiple internet connections and
recommend the proper setup to make sure you are safe on the internet.

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Two connections at the same time

I’ll put it this way: don’t be connected to both at the same time.

If you’re connected to both:

a) You don’t know which connection your computer is actually using.

b) You could easily be using his wireless when you think you’re using your

Manually turn off the wireless

The safest thing to do is to turn off your wireless connection.

If you have a switch, use that. If you don’t have a switch: right-click on
the network connection icon in Control Panel and you should be able to click on
“Disable” to actually turn the adapter off. That way, you can use your USB
connection safely.

Can I be traced?

No, he cannot see what’s going on on your USB.

He can’t see anything if the data is going through that USB connection (which I assume is some kind of cellular modem). Then, no, he’s not going to be able
to see that.

The problem is that (like I said) if you are “simultaneously” connected to
his network, you don’t know where the data is going. You don’t know what he can
or can’t see. So don’t do that.

Do this

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4 comments on “What happens if I am connected to my neighbor’s wireless and my USB modem at the same time?”

  1. There is a way of telling… Open task manager and click Network tab. Although both connections sow some activity for housekeeping, you can see which connection is carrying the traffic. I find windows chooses one and tends to stick to it.

    Unfortunately you can’t control which connection is used (except, as Leo said, by disabling one).

  2. In the multiple Internet Connections. Another point. Depending on his ISP rules, you may be using up his limited bandwith or data usuage. Also, if it is without your neighbors consent it maybe illegal.

  3. I shared a wireless connection once with my friends permission. My friend was logging every website that was visited and he knew every website I went to when I forgot to turn on my VPN.

    I use a docked Lenove X61 Thinpad laptop for my “Desktop” and physically turn off the WiFi with a switch when it is docked and connected to the LAN cable. Since the switch is a software switch, it does not always turn off the WiFi. This is due the Win7 upgrade over riding the original Lenovo drivers. Do not ever trust your physical WiFi switch in critical situations.

    My Belkin router at home has a guest WiFi connection which keeps some sort of firewall or something between my network and guests.

  4. I’d recommend using the same precautions that you would use on a public wifi as you do on your friends wifi. If you regularly use public wifi or your friends wifi, a subscription to a VPN service is a good idea. At the very least I’d download Tor and use that service. Tor is slow but it’s free and works reasonably well.

    If you want to use your wireless internet service instead of your friends wifi, I recommend what Leo says, make sure you turn off your wifi. On many or most notebooks it can be done by a switch or by hitting a function key and then another key that is usually labeled with an antenna symbol. That way you know that you’re not using wifi.


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