nsurlsessiond downloads too much data
There are a lot of posts about this in regards to Yosemite/El Capitan. I personally have a machine w/ OS 10.11.6 and it constantly dl's at 5-10 Mb/sec. I turned off iCloud, tried every reasonable suggestion. I ended up getting little snitch and just denying the culprit, which is the iCloud drive process of nsurlsessiond "isync-edge.icloud-content.com". Even though I have all processes in the OS disabled, this process is being blocked almost every second (I've had my machine on for an hour with thousands of blocked attempts). Granted, this is my old machine I do not use for my primary workflow, so I can afford to do this. If you can update to Sierra, you may not have theses issues, I don't, and I am using the same apple ID on Sierra as I was on the machine that was eating all my bandwidth until manually blocking.