Wake-On-Lan - program description

Modern technologies do not get tired of developing and making users happy. For example, today it was possible to turn on a personal computer at a distance without any effort. There is such a function (WOL) for a long time, but not all users know how it works, and why.

Wake-on-Lan: what is it?

This protocol is designed to remotely turn on the computer, which has a reserve of voltage on the motherboard, thanks to which the power supply can be started. Through WOL, an additional wake-up capability from the wireless network is also configured, if the router supports it.

It will take a similar function to perform a scheduled update of the OS components and backup on computers that are out of the user's physical reach area without the ability to make the switch themselves.

Since modern PCs provide power to the motherboard in the off state, the Wake-up-On-Lan operation, when properly configured, usually does not cause censures.

Principle of operation

For WOL, only two components of the computer are important: the motherboard and the network card. The first one must be connected to an ATX-compatible power supply, allowing the LAN adapter to view all incoming packets. If one of them has a special command containing the MAC address of the network card, it will be given a signal to start the PC power.

Otherwise, Wake-On-Lan (the program for remote launch) does not require the download of additional utilities: this feature is configured via the BIOS.

Magic package

The command mentioned above is called Magic Packet. It is he who must receive a network card to activate the computer startup. It contains the MAC address of the LAN adapter, which is repeated 16 times, and other required information.

This package can be sent from the OS, web site or router using UDP ports 7 and 9. However, if this function is not needed and the PC can be connected to the mains, it should be deactivated, since it negatively affects the battery level.

How to enable WOL

Older computer models, like some new ones, have a Wake-On-Lan setup feature in the BIOS. To do this, it is necessary to know English at least at the initial level, otherwise the user simply will not find WOL, tk. Today this designation is not used in the basic input-output system.

Usually, you should look for something similar in the power management section, for example, a line with the names Wake-Up by PCI device or Power on by Ethernet Card.

However, if the PC is running on Linux OS, you need to install the built-in utility Ethtool to run the function, which will check the WOL support on the network card.

Customize

Because Wake-On-Lan supports Windows 7 on a par with older versions, you can also enable the protocol through the user interface of this OS. To do this, through the "Start" you need to find "Computer Management" and enter the "Device Manager" in order to find the network adapter in the opened list .

Next, right-click on the right mouse button to call its context menu, open "Properties" and go to the "Advanced" tab. In the displayed list, the user should select the Wake on Magic Packet item and set its value to the on position. You do not need to reboot the computer.

To send a power-on request, you need to know the MAC address, host name, subnet mask, and port number used. Download the program to transfer the "magic package" simply. The network is full of various utilities, as well as websites that perform this function online.

Configuring the Router

This item will only be needed if the PC is turned on via the Internet, not the local network. This requires a permanent and unique IP address provided to the user by the provider. Otherwise, you'll have to rent a static external IP address or use a dynamic DNS client, accessing the equipment through its domain name. An exemplary setting consists in setting the NAT translation rule for the IP address used to connect to the Network: UDP protocol, ports 7 and 9.

Next, you need to create a broadcast address for the router, which is also needed to send the packet. Then to the equipment it is required to connect through a special client and enter such commands:

• Ip arp / user address / ff: ff: ff: ff: ff: ff;
• System config-save.

Then the router is rebooted, and the settings take effect.

Wake-on-Lan: TeamViewer

TeamViewer - software designed for remote access to a computer, which in combination with a configured WOL allows you to turn on the device at a distance with less effort. To do this, you need to take a few more steps, except those described above: configure the firewall and the utility itself.

When you go to the firewall, select Rules for Incoming Connections, and then click Create Rule. In the window that opens, click on "For port" and "Next". Then, set the values for UDP ports 7 and 9, allow them to connect (and prohibit its publicity). Finally, it remains only to give the name to the rule and confirm the changes with the "Done" key.

The first step in setting up TeamViewer is to bind the computer to the account. This is required for security, because the software is not designed for illegal actions, therefore, the computer must belong to someone who wants to access it.

Account binding is carried out by entering the e-mail and password from the account into a special dialog box that the user can easily find himself. Once the account is assigned to a PC, you need to configure Wake-On-Lan through the TeamViewer ID. This is useful in case the device does not have a public address.

In the utility network settings, you need to find the "Inbound connections" item and change its value to "Accept". Then, in the same section, you must select "Configuration", and then a dialog box appears with wake-up functions. In "Other TeamViewer applications on your network", the user must enter and add his ID.

How to disable WOL

As soon as Wake-On-Lan is no longer needed, it is better to disable the utility to save battery power and to avoid interference with third-party technology, sometimes arising when you come into contact with the computer on which this function is enabled.

To do this, you need to reverse the steps in the "How to include WOL" section of this article. However, before that you need to go into the properties of the network card and remove all the checkboxes in the "Power management" tab so that the PC remains de-energized after shutdown and can not be turned on by third-party requirement.

Then, in the "Advanced" section, the user should disable the launch of the device through the Magic Packet, and to be sure of the success of the operation, it is necessary to deactivate WOL and in the BIOS settings. This is done in the same branch that was specified above in the text.

How to test the performance of WOL

Test the utility of the utility can only be experienced by being directly next to the PC. This is done with the help of TeamViewer or other third-party programs and resources that allow you to send Magic Packet.

However, there is also one not very pleasant moment: some devices with a configured Wake-On-Lan and authorized inclusion on the network BIOS, independently start the power supply without sending and receiving the Magic Packet. The reason for this is the somewhat increased functionality of Intel's network cards and 3COM, which use not only WOL to send a signal to turn on the PC on a local network. They also involve other events: by default, as a rule, several criteria are set at once, on which the awakening depends.

This problem is solved by changing the adapter settings via third-party software. You just need to remove the extra conditions to make the function work correctly.