How can I determine what is using my broadband?

Hello PBFZ,

Thanks for using Apple Support Communities.

You can use Activity Monitor's Network tab to view how much data each process is taking up on your computer. Take a look at the support article below to learn more.

OS X Mavericks: About Activity Monitor

Take care,

Alex H.

You should be able to click on the one item, and then

select Info, to see what else is involved w/ this kernel.

And check the Console utility, to see what (among so

many) specific items may relate to the use of internet.

Items by Time & Date narrow the field somewhat.

Good luck & happy computing! 🙂