"hosted by" is a bit misleading. If things are as they were, it's easy for students to request foo.mit.edu. Looking at http://web.mit.edu/maps/networks/mit/mit-topology.pdf, 18.244 is E2 (Senior House).
traceroute fuck-the-skull-of-jesus.mit.edu
...
11 nox1sumgw1-PEER--207-210-142-234.nox.org (207.210.142.234) 49.015 ms 52.072 ms 53.086 ms
12 B24-RTR-3-BACKBONE-2.MIT.EDU (18.168.1.26) 49.024 ms 50.020 ms 53.364 ms
13 FUCK-THE-SKULL-OF-JESUS.MIT.EDU (18.244.1.102) 54.338 ms 55.264 ms 55.258 ms
definitely "hosted by".edit: oops, didn't notice you mention senior house. anyway, in my book, on your network = hosted by you.