I think the Syrian regime has decided that it's not in its interest to allow humanitarian corridors, because it's been pursuing a strategy of starving its opposition and laying siege to them. If that remains the case, I think they're going to be impossible to establish and maintain. The problem with the no-fly zone is that it effectively means declaring war against the Assad regime, because enforcing those requires taking out ground-to-air missile defences that the Syrians have installed, and that means striking Syrian army positions, which they'll reciprocate against. It draws the coalition full-force into attacking the regime that's backed by Russia and Iran, and it leads to a very dangerous situation. I'm not sure either of those is a good option.
I think that advocating decentralization within one Syria as a short- and medium-term solution to get the fighting to stop with various cantons, not just the Kurdish canton but other areas in charge of their respective communities until things can calm down a bit, is something Canada could do as a way to calm thing down a bit.