Net neutrality, the longstanding principle that Internet service providers should treat all content and applications in an equal manner faces its toughest test yet this week as the Canadian Radio-television and Telecommunications Commission (CRTC), Canada's broadcast and telecommunications regulator, conducts a hearing on whether ISPs may engage in "differential pricing". My Globe and Mail column notes that differential pricing refers to instances in which ISPs adopt a non-neutral approach to content by charging one price for consumers to download or access some content, but a different price for other content. The issue - sometimes known as "zero rating" for cases in which ISPs do not levy any data charges for certain content - may sound technical, but it has huge implications for how Canadians access and pay for Internet services.