Editing Wake-on-LAN (section)

===Subnet directed broadcasts===
A principal limitation of standard broadcast Wake-on-LAN is that broadcast packets are generally not routed. This prevents the technique being used in larger networks or over the Internet. [[Subnet-directed broadcast]]s (SDBs)<ref>{{cite book |chapter-url= http://rtfm.adamant.net/books/tcp-ip_illustrated/broadcas.htm |title=TCP/IP Illustrated, Volume 1: The Protocols |chapter=Chapter 12. Broadcasting and Multicasting |first=W. Richard |last=Stevens |year=2007 |archive-url=https://web.archive.org/web/20141106194636/http://rtfm.adamant.net/books/tcp-ip_illustrated/broadcas.htm |access-date=28 October 2015|archive-date=2014-11-06 }}</ref><ref>{{cite web |url=http://www.rhyshaden.com/ipadd.htm |title=IP Addressing |first=Rhys |last=Haden |work=Data Network Resource |access-date=28 October 2015}}</ref> may be used to overcome this limitation. SDB may require changes to the intermediate router configuration. SDBs are treated like unicast network packets until processed by the final (local) router. This router then broadcasts the packet using a layer-2 broadcast. This technique allows a broadcast to be initiated on a remote network but requires all intervening routers to forward the SDB.<ref>{{cite web |url=http://support.amd.com/TechDocs/20213.pdf |archiveurl=https://web.archive.org/web/20141006072000/http://support.amd.com/TechDocs/20213.pdf |title=Magic Packet Technology (White Paper, Publication# 20213, Rev: A Amendment/0) |work=AMD |date=November 1995 |access-date=28 October 2015 |archive-date=6 October 2014}}</ref><ref>{{cite web |url= https://technet.microsoft.com/en-us/library/bb632807.aspx |title=About Subnet-Directed Broadcast Wake-Up Packets for Wake On LAN |work=Microsoft System Center Configuration Manager |year=2007 |archive-url=https://web.archive.org/web/20170630165037/https://technet.microsoft.com/en-us/library/bb632807.aspx |access-date=28 October 2015|archive-date=2017-06-30 }}</ref> When preparing a network to forward SDB packets, care must be taken to filter packets so that only desired (e.g. WoL) SDB packets are permitted{{snd}}otherwise the network may become a participant in [[DDoS]] attacks such as the [[Smurf attack]].<ref>{{cite web |url=https://www.packetcoders.io/local-vs-directed-broadcasts/ |title=Local vs Directed Broadcasts |date=5 April 2018 |access-date=2023-12-07}}</ref>