I think you start by looking at what you have to do. The northern bit of Canada is 40% of Canada, so it's huge. We have the second biggest country in the world. In no way have we ever had the resources to effectively patrol it or do search and rescue. Whatever assets are provided by whatever government will, by enabling better search, be more effective in the execution of their duties.
It's about better information. Some of it is satellite-based; much of it, I'm saying, can be done locally, out to hundreds of kilometres from a particular base. By having multiple ones, now you have a system that provides accurate and timely information to those commanders who need to get things done.
I don't really care how they do it, but blisters on the side of an aircraft was very World War II.