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I know Wake-on-LAN standard, but I don't understand the use case for Wake on Pattern Match option in the network card preferences. What are the advantages of it?

1 Answers1

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“Wake On LAN” makes the system wake on the “magic packet.”

The “Wake on pattern match” option instead checks for packets that matches the operating-system-specified patterns; for example, an ARP request for the computer’s address, or a TCP connection attempt.

The default patterns on a Windows 7 system are:

  • Magic Packet.
  • NetBIOS Name Query.
  • TCPv4 SYN.
  • TCPv6 SYN
  • IPv6 Neighbor Solicitation.

There’s no ARP in the list since the device is expected to support “ARP Offload”; that is, reply to ARP requests with OS-set address by itself.

u1686_grawity
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  • Does anyone know if an article exists explaining the other advanced features available for network interfaces on Windows? Google doesn't turn up any quality results for all but a few of the more obvious options. – Hydranix Mar 30 '16 at 04:28
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    Only by disabling `Wake on Pattern Match` on my network card could I wake my computer over the Internet. Important note: this option did not impair waking over LAN. – NikolaiK. Jul 08 '16 at 21:54
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    In some networks, "wake on pattern match" will wake the computer when you don't want it to happen, since other devices on the LAN might be sending the aforementioned packets to your NIC. I had this experience on both an IPv4-only and an IPv6 LAN. I had to turn it off. – John M. Kuchta Mar 25 '21 at 17:29
  • What I really want to know is does the "Only allow a magic packet to wake the computer" in the Power Management settings of the adapter override the fact that Wake on Pattern Match is enabled. Naturally I think from now on I will leave both the Only allow checked and disable Wake on Patten Match. But it would be very nice to know if checking the Only allow magic packet checkbox is sufficient to produce the desired behavior (prevent random computer wakeups)! – Steven Lu Mar 16 '22 at 05:31
  • @StevenLu: My understanding is that this checkbox in "Power Management" is what's supposed to _control_ whether Wake on Pattern Match is enabled or not, and if a driver adds a custom parameter that does the same thing, then their interaction is going to be driver-dependent (pretty much all parameters you see in "Advanced" are custom-defined by the driver and not by Windows). – u1686_grawity Mar 16 '22 at 05:38
  • Yeah. it's just that setting the checkbox does not make any modifications to the Pattern Match setting. Anyway, putting both settings in the suitable place definitely makes it work as desired. – Steven Lu Mar 16 '22 at 17:04