Using a Network Connection to Wake Up a Sleeping Computer
Most Windows 7
computers are configured to go into sleep mode after a certain amount of
idle time. If you’re coming to Windows 7 from Windows XP, then sleep
mode is the low-power state that Windows 7 uses to replace the confusing
standby and hibernate modes from Windows XP. (Standby mode preserved
your work and enabled you to restart quickly, but didn’t entirely shut
off the machine’s power; hibernate mode preserved your work and
completely shut off the machine, but also took a relatively long time to
restart—faster than shutting down your computer entirely, but slower
than standby.)
Windows 7’s sleep state combines the best of the old standby and hibernate modes:
As in standby, you enter sleep mode within just a few seconds.
As in both standby and hibernate, sleep mode preserves all your open documents, windows, and programs.
As
in hibernate, sleep mode shuts down your computer, except it maintains
power to the memory chips so that it can preserve the contents of RAM
for when you restart.
As in standby, you resume from sleep mode within just a few seconds.
To use sleep mode, you have two choices:
To launch sleep
mode by hand, open the Start menu, click the arrow beside the Shut Down
button, and then click Sleep. Windows 7 saves the current state and
shuts off the computer in a few seconds.
To configure Windows 7 to go into sleep mode automatically, select Start, type sleep,
and then click Change When the Computer Sleeps. Use the Put the
Computer to Sleep list to select the number of minutes or hours of idle
time after which Windows 7 automatically puts the computer to sleep.
Click Save Changes.
Having a computer go to
sleep when you’re not using it is a good idea because it conserves
power. However, it can be a pain if you need to access the computer
remotely over your network because you have no way to wake up the
sleeping computer (which normally requires a physical action such as
jiggling the mouse or pressing the computer’s power button).
Fortunately, most new NICs support a feature called wake-on-LAN, which enables the NIC to wake up the computer when the NIC receives a special Ethernet packet called a magic packet (usually the hexadecimal constant FF FF FF FF FF FF followed by several repetitions of the computer’s MAC address).
For this to work, you must first configure the NIC to handle wake-on-LAN. Here are the steps to follow:
1. | In
the Network Connections window, right-click the connection that uses
the NIC you want to configure, and then click Properties. The
connection’s Properties dialog box appears.
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2. | In the Networking tab, click Configure to open the NIC’s Properties dialog box.
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3. | Display the Power Management tab.
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4. | Click to activate the Allow This Device to Wake the Computer check box.
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5. | Click to activate the Only Allow a Magic packet to Wake the Computer check box (see Figure 5).
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6. | Click OK.
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Note
If
the Allow This Device to Wake the Computer check box is disabled, it
probably means your NIC doesn’t support wake-on-LAN. However, it may
also mean that this support has been disabled. In the NIC’s Properties
dialog box, display the Advanced tab and look for a property named Wake
Up Capabilities. Click this property, and then choose an option in the
Value list (such as Magic Packet or On). Click OK to put the new setting
into effect, and then retry the steps in this section.
With the computer’s NIC
configured, you need to download a utility that can send a magic packet
to the remote computer whenever you need to wake up the machine. I use
MatCode Software’s free Wake-on-LAN utility, available at www.matcode.com/wol.htm. You can also try Googling “wake-on-LAN utility.”
Tip
When you use the
wake-on-LAN feature, you probably don’t want the remote computer to wake
to the Windows 7 Welcome screen. Instead, it’s almost always better to
have the computer wake directly to the desktop. To disable the password
requirement on wakeup, select Start, type wake,
and then click the Require a Password When the Computer Wakes link to
open the System Settings window. Click Change Settings That Are
Currently Unavailable to enable the options. Activate the Don’t Require a
Password option, and then click Save Changes.
Disabling a Network Connection
It’s possible that your
Windows 7 computer has a network connection that it doesn’t use. For
example, if you upgraded to a Gigabit Ethernet NIC, you may no longer
use your machine’s old Fast Ethernet motherboard NIC. You can’t detach a
motherboard NIC from your computer (not easily, anyway), so the network
connection icon remains, cluttering the Network Connections window and
using up a few Windows 7 resources. If you don’t plan on using such a
connection, you’re better off disabling it by following these steps:
1. | In
the Network Connections window, click the connection you want to work
with, and then click the taskbar’s Disable This Network Device command.
(You can also right-click the connection and then click Disable.) The
User Account Control dialog box appears.
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2. | Enter your UAC credentials to continue.
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Windows 7 changes the connection’s status to Disabled. If you want to use the connection again later on, click it, and then click the taskbar’s Enable This Network Device command.
