Undernet also runs an open proxy scanner. This scans users currently connecting to the network for open WinGate, SOCKS version 4/5, and HTTP proxy servers. IP addresses hosting open proxy servers are automatically G-lined from the network. These changes were put in place after the 2001 Denial-of-service attacks almost destroyed the network and left Undernet without the registered channel service bot for months. In 2010, Undernet also started to g-line Tor exit nodes, instead of assigning those users a cloak like e.g. Quakenet.