Apple’s implementation of AirDrop relies on Wi-Fi chipsets that have built-in PAN support. This reliance on hardware-based PAN capabilities in Wi-Fi chipsets has the unfortunate consequences of limiting the use of AirDrop to Macs released in late 2008 or later. The restrictions apply to third-party wireless products as well; they need to have a built-in Wi-Fi chipset that supports PAN. It also prevents you from using AirDrop on other types of local networks, such as good old-fashioned wired Ethernet, which isn’t many people’s network of choice anymore at home but may still be in many offices. However, as an anonymous tipster reported to Macworld OS X Hints, there is a workaround that enables the use of AirDrop not only over non-supported Wi-Fi connections but also by Macs connected to a wired Ethernet network.

How AirDrop Works

AirDrop uses Apple’s Bonjour technology to listen in on a Wi-Fi connection for another Mac to announce AirDrop capabilities. AirDrop announces itself over any available network connection, but when AirDrop listens, it only pays attention to Wi-Fi connections, even if AirDrop announcements are present on other network interfaces. It’s not clear why Apple chose to limit AirDrop to Wi-Fi, but it appears that Apple, at least during testing, gave AirDrop the ability to listen for AirDrop announcements over any network connection. Select the AirDrop entry in the Finder window sidebar, and all Macs on the network with AirDrop are visible. Dragging an item to one of the listed Macs initiates a request for a file transfer. The user of the target Mac must accept the transfer before the file is delivered. When the file transfer is accepted, the file is sent to the designated Mac and shows up in the receiving Mac’s downloads folder.

Supported Mac Models

Macs that support AirDrop include:

Disable AirDrop on Any Network But Your Wi-Fi Connection

Not Ready for Prime Time

Although AirDrop works well when used in its default configuration over Wi-Fi, you may encounter a few gotchas with this non-Apple-sanctioned method for using AirDrop over other network connections. The command appears all on one line with no line breaks. Your web browser may show the command on multiple lines. If you see any line breaks, ignore them.

You may have to restart your Mac after running the Terminal command before the AirDrop capabilities are applied. This includes enabling or disabling the AirDrop feature. AirDrop usually lists nearby Macs with AirDrop capabilities. From time to time, AirDrop-enabled Macs that are connected by wired Ethernet drop off the AirDrop list and then show up again later. Enabling AirDrop over any network appears to send data in an unencrypted format. Normally, AirDrop data is sent encrypted. It is best to limit this AirDrop hack to a small home network where all users can be trusted. Enabling AirDrop over any network causes AirDrop to only work for Macs that are on the same network; no ad-hoc connections are allowed. Using OS X’s standard file sharing system may be a more stable method for file transfers on a wired network.