Talk:Wake-on-LAN/Archive 1

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Origin of WOL[edit]

The German Wikipedia states that WoL was published in 1995 by AMD and HP. They link to http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/20213.pdf. Neither Intel nor IBM is mentioned there. If it were Intel/IBM - why should they cooperate? why does AMD have the patent for it? I recommend to check this and link to a source for this claim. Zefiro 21:47, 31 October 2005 (UTC)[reply]

Disputed text:

It is an Intel Wired for Management System product.
It was developed as part of the IBM and Intel Advanced Manageability Alliance.
I intend to follow this up sometime in the next few days. (This should not prevent anyone else from doing it first!) --LesleyW 03:36, 24 November 2005 (UTC)[reply]
I did a search on patents and trade marks (www.uspto.gov), I could not find any patents but it confirms that IBM holds trademark for "Wake on Lan" which is different from "Magic Packet". This probably means that they also have a patent. If someone knows how to search the patent database it would be useful to provide some information. As far as I know this is a proprietary technology and not a standard. I could not find any standards for it. Therefore I suggest that opening to be changed to reflect this. Mahanchian 15:21, 28 February 2006 (UTC)[reply]
Top of page 4 of the AMD white paper reads "However, a method of solving the above problem was presented by IBM engineers...". No mention of Intel though. --64.81.114.101 05:48, 10 June 2006 (UTC)[reply]
After a little more searching, found http://www.liebsoft.com/index.cfm/whitepapers/Wake_On_LAN which discusses the IBM / Intel Advanced Manageability Alliance. I think that should be enough to resolve the dispute. If you agree, please archive this thread and remove the tag from the main page. --64.81.114.101 06:10, 10 June 2006 (UTC)[reply]

Linkage[edit]

This article links to itself, through the "wake-on-ring" and "wake-on-modem" links which both redirect back to Wake-on-LAN. I have removed the useless links, but I think there might be a case for a separate "wake-on-ring" article as it's not exactly the same thing. Or maybe both could be covered under a more generic title such as Remote Wake-up. --LesleyW 03:36, 24 November 2005 (UTC)[reply]

The phrase "Ethernet Packet" is used, I believe the author meant an Ethernet Frame.

Dedicated header[edit]

Do you still need a header to bring a computer using Wake on Lan up? Obviously integrated cards do not have this problem but I've seen discrete PCI cards that do have any headers or leads on them but which claim to do Wake on Lan (and have driver support). Is it possible for arbitrary PCI cards to bring a machine back up if the BIOS is set correctly?

I've just seen this: http://support.intel.com/support/network/sb/cs-008459.htm#2a

The header is only needed for older machines using APM and not ACPI? -- 81.96.206.228 08:17, 17 June 2006 (UTC)[reply]

There's another nice WoL writeup on Everything2: http://everything2.com/index.pl?node_id=1675677

No, you need the header, of course. The wake-on-LAN UDP packet itself is a broadcast packet, meaning that the IP address must be the broadcast address for that subnet, or the entire network, depending on what you want to wake up. The destination port will be 9, although I think that you can use 7 as well. I think I'll add this to the article.

That's a different kind of header. I believe the OP was referring to the three-lead header on the NIC. The answer to the OP's question is, "No, it is not always necessary." The modern versions of PCI (2.x?) provide a +5VSB (standby +5 volt) connection to the power supply; most power supplies provide a few watts while the system is "off" (soft-off) to the motherboard (and thus to PCI's +5VSB). jdstroy (talk) 02:13, 4 March 2008 (UTC)[reply]

Corrections, expansion and citations[edit]

This article was in dire need of some clean-up and corrections which I think my revision helped considerably. However, there are no citations and I think the History section should be expanded. Anyone want to take a crack at it? Phrackattack 21:41, 18 August 2006 (UTC)[reply]

I have removed 80.137.255.41's addition which described the Magic Packet as being broadcast or unicast. This is not the case; the magic packet is always transmitted via broadcast. Phrackattack 22:13, 29 August 2006 (UTC)[reply]

It cannot use unicast because that would likely require an ARP operation, which would fail due to the unavailability of the target adaptor.

Unless you have a static ARP table entry? Not sure about it, though... 11:06, 2 December 2006 (UTC) Kosma

I'm pretty confident that static ARP would permit a unicast WoL packet to signal a soft-off device. jdstroy (talk) 02:15, 4 March 2008 (UTC)[reply]

Not for wireless ethernet[edit]

It should be mentioned that Wake-on-LAN will not work for wireless ethernet (WiFi, 802.11-series standards) because the radio is powered off at these times.

According to my experience and the LAN page, Wi-Fi is an implementation of a "LAN". ~Kruck 23:53, 14 December 2006 (UTC)[reply]
WiFi/802.11 may reasonably be called LAN, but they are not Ethernet. Zodon (talk) 01:20, 2 April 2008 (UTC)[reply]
Technically Wi-Fi/802.11 is not Ethernet. But according to the Wi-Fi article, Wi-Fi has been referred to as "wireless Ethernet" by the originators of the Wi-Fi standards (if not by the IEEE 802.11 working groups). Maybe that's just because these days almost all LANs use Ethernet (now that good old Arcnet, Token Ring, et. al., have all but disappeared). Seitz (talk) 05:03, 3 April 2008 (UTC)[reply]

After power loss?[edit]

Does WOL still work after a computer has lost power from, say, a power outage? 205.157.110.11 23:07, 20 September 2006 (UTC)[reply]

It does not. While the power is off, there would be no source of power to keep the NIC card listening. Phrackattack 20:18, 22 September 2006 (UTC)[reply]

  • As long as a fuse or circuit breaker wasn't tripped, so that power would be available to the computer and networking equipment, remote wake-up procedures will work AFTER a power outage. This assumes that the outage is over. Unless the equipment was physically damaged by the power outage, once power is restored, the PSU would still supply power to the motherboard, returning it to a standby state.
  • Not all NICs will allow you to WOL after a power outage. Some require the OS to explicitly configure it for WOL before powering off. Ldkronos (talk) 13:15, 12 January 2008 (UTC)[reply]
To summarise the previous comments (I don't want to edit others' comments): The computer obviously won't start until power is restored. Some, but not all, motherboard + NIC combinations will allow WOL after power loss. A motherboard of mine (Gigabyte 8KNXP, ~2004) has a BIOS setting that allows the machine after sudden power loss to power up on, off, or in the state at power loss; this sort of feature can help to keep unattended machines accessible. I don't know if it's a usual feature. Pol098 (talk) 23:11, 17 April 2009 (UTC)[reply]

Types of Remote Wake Up (RWU)[edit]

Wikipedia has (or should have) a lot of short articles about turning on a computer remotely - I think this is the longest one. I would think the very similar ways to remotely wake a computer should be consolidated into one article. What do you think? These were the similar article topics I was considering:

  • Wake on LAN (WoL)
  • Wake on WAN (WoW)
  • Remote Wake-Up (RWU)
  • Wake-on-Ring (WOR) / Wake-on-Modem (WOM)

~Kruck 23:58, 14 December 2006 (UTC)[reply]

Seems reasonable. Might also add Wake on time or Timer. Zodon (talk) 00:17, 2 April 2008 (UTC)[reply]
  • Wake on LAN (WoL)
    • Wake on Magic Packet (if hibernating or standing by)
    • Wake on Magic Packet (even if off (S5))
    • Wake on Directed Packet
    • Wake on Link

Pol098 (talk) 23:16, 17 April 2009 (UTC)[reply]

WoL programs section seems a bit spammed[edit]

Somebody should check the Wake-on-LAN programs section and remove the spam. Petr Matas 16:51, 22 December 2006 (UTC)[reply]

if you know what spam there is just remove it Markthemac 04:19, 19 June 2007 (UTC)[reply]

WoL and dynamic VLANs[edit]

Is WoL incompatible with networks using dynamic VLANs? I would guess it is since the mac address of the sleeping computer will not be known to the switch... 81.96.206.228 20:01, 3 July 2007 (UTC)[reply]

It works fine on 802.1Q VLANs. You'll need to know the hardware address, still. What I've seen happen is a system soft-poweroff (and power-on) will reset a network adapter; so the VLAN settings are retained in the OS configuration, and not on the network adapter. This means that whatever VLAN options you set are set after the OS has started, and NOT retained when the system is off. The network adapter will respond to normal WoL requests as if it was not on a VLAN. (all of that before was about Management VLANs.)
Notice, above, there's talk about not being able to resolve IP addresses through ARP. Static ARP entries should solve the problem. Likewise, this will work on a VLAN (assuming you're using intelligent switches at the edge to tag packets). jdstroy (talk) 23:53, 16 April 2008 (UTC)[reply]

LAN <> Internet ?[edit]

As far as I know, the Internet is not commonly considered "LAN". But it seems to be possible to wake-up computers using WoL over the Internet? If WoL is supposed to work also on Internet/WAN, maybe we should have a little comment about this in the article. -- Peter 20:57, 10 September 2007 (UTC)[reply]

Wake on LAN basically means "Wake on LAN activity", because NICs in computers are colloquially called "LAN cards". Because it is possible to access a computer via its network card (read: LAN card) over the internet, it is obviously possible to use "wake on LAN activity" on that same computer. The feature is not very well named - it should really be called "wake on network" to make it clear that Local Area Network technology really has nothing to do with the actual feature. 202.49.72.33 02:29, 1 October 2007 (UTC)[reply]
Thanks for the explanation, that clears it up for me. However, network activity / network cards are not commonly described as LAN activity / LAN cards. Not every computer connected to the Internet, is also connected to a LAN. I will put a small notification in the article. -- Peter 21:51, 22 October 2007 (UTC)[reply]

Also, it is mentioned that the magic packet must be broadcasted e.g. using the broadcast address, but it won't reach the remote computer throught the internet, as is will most likely be filtered. Any comments? —Preceding unsigned comment added by 130.225.243.86 (talk) 14:58, 17 December 2007 (UTC)[reply]

Yes, that's true, but there are workarounds to that: you can forward the port (any port, by the way - the article seems to imply that only ports 0, 7 and 9 can be used, but WoL works over any port, I've just edited the article to reflect that) to the internal host behind the firewall / router. That's the catch really: you have to forward to the specific host, instead of forwarding to the internal broadcast address, because most routers don't support the latter. Then if you need WoL to work for more than one host inside a LAN over the internet, you need to have a port-forward for each host (each using a different port, of course). --CronoT 16:03, 5 March 2008 (UTC)
But how does the NAT router forward to the specific host, when the specific host is powered off and can't respond to ARP? 128.107.248.220 (talk) 19:37, 21 March 2008 (UTC)[reply]
It is possible to send it via static ARP. It is also possible to send it to a set (range) of hardware addresses (e.g. if you know you purchased a bulk series of network controllers, either integrated or discrete). jdstroy (talk) 23:47, 16 April 2008 (UTC)[reply]

Extra Elaborations Needed ?[edit]

Note: I don't have enough knowledge to improve this article. If possible, I would like to see the following questions addressed:
- Does WOL start the PC if its operating system has been stopped (Windows and Linux) or put into hibernation mode (Windows), assuming the system is connected to a power source, and the network card is still receiving power?
- Does it work if the system is in standby mode?
- Can it be integrated into other applications, for instance, archival back-up or music streaming software, that need to access a hard disk on a remote server, if the server is powered-off or in standby? I'm referring to home usage here, where it might not be desirable to keep the server running 24/7.
- How do the listed programs work if the destination machine is behind a firewall, and gets its IP address from the firewall via DHCP? The programs require the user to specify the destinations machine's IP address (and MAC address), but if the machine is behind a firewall, it will have a private address 192.168.x.x or 10.10.x.x.

Let's see if I can address your questions here. I'm not a very good writer in terms of WP style, so it's much easier just to answer it here and let someone else insert it in to the article.
  • Often, but not always will WoL start the computer. On Windows, an option (checkbox) in the properties pane of the device in Device Manager allows a user to persist Wake-on-LAN settings between sessions; one check box wakes the computer on any network activity, and the other wakes the computer if a WoL packet is sent from the network. In Linux, the setting must be enabled (usually per startup) to have it persist. (Does that mean that if the computer fails to boot and powers off before setting the WoL flag, that it will not respond to magic packets afterwards?)
  • Yes, it works on standby.
  • Sure, but I've not seen such an application [integrated multimedia/WoL] yet.
  • It works fine; usually it's a broadcast packet (see exceptions mentioned above?), and may be enclosed in a broadcast Ethernet frame, too. If the computer is behind a firewall, the firewall would need to let the packet through in order for WoL to work. Again, since it's usually broadcast across a network, it is usually unicast across the Internet, and *then* broadcast through the network on the firewall/residential gateway.
Perhaps a twisted example, but suppose that there's a SOCKS proxy at the perimeter between a private network (with, perhaps, NAT) and a public network (the Internet). The SOCKS proxy can receive an incoming connection over TCP on the Internet to request a UDP datagram to be sent to the internal network (bad security administration, I know). The SOCKS proxy server will deliver the packet to the internal network (10.0.0.0/24;172.16.0.0/16;192.168.0.0/16) and will wake up the machine. Essentially, SOCKS tunnels the packet over a public network in to a private network, and it works. jdstroy (talk) 02:36, 4 March 2008 (UTC)[reply]

Another gap in the article imho: the receiving side is described, but there is nothing about the sending side. How is the dispatching of the magic packet triggered ? (unsigned)

Most of the points above seem now to be dealt with adequately in the article. Pol098 (talk) 17:34, 25 June 2009 (UTC)[reply]

Get rid of the tags.[edit]

The advisory admin tags are starting to really annoy me. I don't come here to read:

"This article needs additional citations for verification."

"This article may require cleanup to meet Wikipedia's quality standards."

"The external links in this article may not comply with Wikipedia's content policies."

Even if I did come here to read edit tags (Hint: I don't), I wouldn't need to have them cluttering up the main article. Put them on the discussion page. Or create a new page where admin types can put all their own tags. Let them invent their own new tag types to put on the tag page.

You think your admin/edit tag is the most important thing on the whole page, right? That's why you put it at the top, and give it a special format? Grow up. 150.101.166.15 00:36, 8 November 2007 (UTC)[reply]

Other machine states and LAN wakeup signals[edit]

WOL used to be fairly simple: machine off but plugged in, send magic packet, machine switches on. Now it's become very complex: 6 power states (S1-S5 and unplugged), 3 ways of waking (magic packet, directed packet, on link), maybe 10 interdependent settings to control it all, PME on PCI >=2.2, etc. The problem is very often how to put the machine to sleep without it being woken by normal LAN activity (Wake On Trash).

The article didn't reflect this; I've added a section, but it could do with attention from others. I've found no useful general references; for any system you need the motherboard manual, NIC manual, knowledge of network traffic and, to be fully in control, a network analyser.

Unless somebody comes up with something better, maybe the following rule of thumb could be added: set the motherboard to support all wakeup signals and the NIC only to wake up on magic packet. It means you can't automagically wake up the machine when it's asked for information, but it won't keep switching itself on.Pol098 (talk) 23:01, 17 April 2009 (UTC)[reply]

Consistency: "Wake on LAN" vs. "Wake-on-LAN"[edit]

This article is not consistent with respect to using "Wake on LAN" or "Wake-on-LAN". It should be decided what is the correct/preferred term.

The same is the case for "WOL" or "WoL". —Preceding unsigned comment added by Mortense (talkcontribs) 19:03, 26 August 2009 (UTC)[reply]