HP Wireless Wakeup - Technical whitepaper
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Technical white paper | HP Wireless Wakeup
1 HP Wireless Wakeup
1.1 Purpose
The purpose of this whitepaper is to describe the HP Wireless Wakeup feature and how to congure it on supported HP
notebook systems.
1.2 HP Wireless Wakeup overview
HP Wireless Wakeup, also commonly known as Wake on Wireless LAN (WoWLAN), is a technology that can be used
to remotely wake up computers connected to a wireless network in order to facilitate IT administration and system
management. This HP Wireless Wakeup technology is based on the same concept as the Wake on LAN that is used
in a wired network. An encoded broadcast packet, known as a “wakeup magic packet,” is sent from a remote system
management application in order to wake up the client computer from a system power-saving state such as standby (S3)
or hibernation (S4). The industry-standard wakeup magic packet is a broadcast frame that contains 6 bytes, each set to
255 (FFh), and sixteen repetitions of the target computer’s MAC address. It is sent typically as a UDP packet to port 7 or 9.
As the enterprise shifts to an all wireless network environment and the industry is trending to eliminate the traditional
Ethernet adapter from thin form factor notebook client devices, the key benet of HP Wireless Wakeup is enabling the
management of enterprise clients the same way as in a wired network environment.
In order to support wake in a wireless environment, there are several dependencies.
• Client devices must be able to wake from a power-saving mode by a wireless network adapter.
• Client devices must be designed to maintain power to the wireless network adapter during system power-saving states
in order to allow the wireless adapter to keep its association with a wireless access point.
• The wireless network adapter must support wake function and be able maintain a wireless association with a WLAN
access point during supported system power-saving states.
• The OS must allow the conguration of the wireless network adapter to enable WoWLAN function.
• The client device must be associated with a wireless access point prior to entering a system power-saving state, and the
association must persist during the system power-saving state so that the adapter can listen for a wakeup packet. If the
client device loses its association with the wireless access point for any reason (for example, if the client device is moved
out of the access point’s range) while in a system power-saving state, then the wake function will no longer be available.
• Network infrastructure must be congured to allow wireless broadcast packets to traverse the network so that the
wake magic packet reaches the client devices.
Typically, after a client system is awakened, a separate management solution is used to perform administrative actions
such as system update or patch, inventory, policy update, etc. The conguration and operation of these IT administration
and management application suites are beyond the scope of this whitepaper.