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computer sends info through LAN connection after powering of

I install satellite internet for a living. I'm not new to computers.
Today I ran across something disturbing. A customers computer that was still sending information via the LAN connection onto the internet after power shut down!
Let me say the computer was not asleep...I checked. It wasn't powering off, it was dead as a door nail shut the *&%$ off!
I know of nothing that can perform this miracle of technology short of government intervention. Please someone tell me you know of a virus that can do this. Otherwise I believe I may have just left an FBI stakeout!
I don't have any specifics on the computer. I just want to know for curiosities sake if anyone has ran across this before.

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Most common?

In reply to: computer sends info through LAN connection after powering of

You didn't tell how you know it is sending data. Many look at blink lights on a router and think that's it. However it is not unusual for a router to respond to PING and such will look as if there is data flow.

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reply to R. Proffitt

In reply to: Most common?

R. Proffitt,
I apologize, R. Proffitt, On our modem I can tell if the modem or computer is transmitting. I can also tell if the LAN is transmitting. There are a series of lights that tell a technician exactly what the modem or computer is doing.
The LAN (ethernet connection) should not be communicating if the computer is off. The modem was communicating with the computer. The modem was also transmitting and receiving a LOT of data....not just your average modem maintaining a connection.
The computer was soooo slow it took 2 hours to do 20 minutes worth of setup. I shut it off to hard reboot and attempt to speed the computer up. Thats when I I noticed that the thing was still connected. I had to unplug the computer to stop the communication.

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The network interface device

In reply to: reply to R. Proffitt

The PC will have a network card or MB Ethernet device. The MB will still have +5v active even with the PC turned off unless AC to the PS is interrupted. That +5v that allows you to use a momentary contact switch to power up the PC also allows for wake-on-lan (WOL). The Ethernet device is still able to detect LAN activity and the LED on the router or switch will show the electrical connection. If the WOL feature is turned on, the Ethernet device is awaiting a specific packet of data that tells it to power on the PC. This may be the activity you see.

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wake on LAN activity

In reply to: The network interface device

I thought of that. If this were the case wouldn't the computer become fully awake upon LAN activity. I install an average of three customers a day and I've never encountered this before. when you consider the unique set of circumstances (unique to my experience) this stands out.
We check for connectivety on every job. In hundreds of installs I've never encountered this.

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No, it wouldn't wake the PC upon any LAN activity

In reply to: wake on LAN activity

It looks for a specific packet of data that includes its MAC address. Any random activity is ignored. That's how WOL works. The LAN activity needs to be there and the NIC responds only to a specific packet of data meant for it.

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The words.

In reply to: wake on LAN activity

Research "MAGIC PACKET" and you should find that.

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Just A Thought.. Is The Modem/Router Also Wireless?

In reply to: reply to R. Proffitt

Although the client's computer may be wired, there could be other outside forces connecting wirelessly to the router/modem.. Possible?

Hope this helps.


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