Use unicast for sending wake-up packets Unicast is more secure than subnet-directed broadcasts because the packet is sent directly to a computer rather than to all computers on a subnet. However, unicast will not work in all environments. For more information, see Choose Between Unicast and Subnet-Directed Broadcast for Wake On LAN.
If you must use subnet-directed broadcasts, configure routers to allow IP-directed broadcasts only from the site server and only on a non-default port number Subnet directed broadcasts are vulnerable to smurf attacks. Limiting the broadcasts to a trusted source, the site server computer, and a non-default UDP port, help to mitigate the risk. For more information, see Secure Routers for Subnet-Directed Broadcasts for Wake On LAN.