Jerome Tissieres writes:
From behind SWITCH; www.cablecom.ch is not known and www.cablecom.net goes to a godaddy sponsor page.
Some of our anycast nameservers had cached the temporary delegation and NXDOMAIN responses for ns{1,2}.cablecom.net. Unfortunately we only heard about it this morning. Caches have been cleared. But note that universities usually operate their own DNS caches rather than using ours.