Nt authority\ system shutdown

I have seen shutdowns before but i cant figure this one out and i cant find anything on my computer as far as viruses. the message reads as follows :
NT Authority\shutdown

Reboot was initiated by Allure ClusterCATS
IP Alias Daemon due to an IP Adress conflict.

I am on a wireless network at home and is set as private with a password and I am the only computer using the network. I have a laptop wich with I connect. Anywaone please help. this also only happens after the computer has been sitting with no action for a while. rarely does it happen in the middle of any work. Anyone please help!!!!