Credit: Cornell University

We mostly take that Ethernet cable for granted: Plug it in and you're connected to the Internet. Go wild!

But as always, the free lunch isn't really free. In addition to the costs of shuffling messages around the campus, Cornell pays by the byte for whatever crosses the border to the wider Internet, both in and out. To recover those costs fairly across all users, Cornell Information Technologies (CIT) created Network Usage-Based billing (NUBB). It works a little like cell phone charges: Each workstation is allowed up to 5 gigabytes per month of off-campus traffic for a standard fee; after that, there's a charge of a fraction of a cent per megabyte.

That worked fine until Wi-Fi came along. Now about 16 percent of Cornell's off-campus traffic goes through the RedRover Wi-Fi network, and most of that usage is by students, according to CIT marketing analyst Beth Lyons. So, beginning June 1, CIT will begin tracking student network usage by NetID instead of by IP address so that Wi-Fi usage is included, while increasing the monthly threshold for students from 5 to 10 gigabytes a month.

These changes are not meant to be punitive or to suggest that using more bandwidth is a bad thing, Lyons said. They're simply to ensure that costs are allocated equitably.

The changes apply only to Internet usage to or from sites beyond the campus network. The use of campus resources such as the Library Gateway, checking grades, Blackboard, and file transfers between two campus systems don't count. E-mail and e-mail attachments are also exempt, even to or from off-campus addresses.

None of these changes apply to faculty or staff, whose computers will still have a 5-gigabyte threshold per month and whose Wi-Fi usage will not be included — so far, anyway.

In April and May, students will be able to visit a Web page that will report their current wired and Wi-Fi usage and preview what the NUBB charges would be for that usage if the June changes were in place. Current numbers indicate that 90-95% of students will not see any usage-based charges as a result of the change, Lyons reported.

The 10-gigabyte monthly allocation is approximately the amount of data stored in 2,400 MP3 files or up to eight full-length feature films.