See map. 215 entrance is on in the little corridor whose entrance is between rooms 210 and 208 on the second floor off the Rideau Canal Atrium. Other rooms in the corridor are 211-214.
215 will be the second room for the MSR conference Monday and Tuesday, which also uses 214 next door.
215 and 214 will be temporarily turned into a single room Morning since the joint ICPC/MSR keynote will be here.
During the main conference days (Wed-Fri) a main theme of this room will be SE for AI.