While testing a honeypot solution on our network I noticed some interesting traffic. I was seeing consistent UDP broadcasts (port 43440) from various ThinkPads on our network. The packet showed "Lenovo ThinkPad" in clear text but nothing else helpful. After more research I discovered these broadcasts were generated by the power management driver on the Thinkpad. The only way to stop the broadcasts was to stop the power management service.
But it seemed odd the power management service would send UDP broadcasts. More research indicated this was part of the Cisco EnergyWise initiative. This is designed to allow hardware manufacturers a method to manage power settings on network-attached devices via a Cisco switch. Several hardware companies are on-board but Lenovo appears to be the only PC or laptop manufacturer that's participating. [more]