The solution is easy. Instead of banning a specific usage pattern, just say that anyone who exceeds 100 GB / month [1] of usage gets their speed cut to 10% [1] for the rest of the month [2].
It's simple and obvious and I'm amazed that Google, of all companies, isn't smart enough to figure this solution out on their own.
From the ISP's point of view, their infrastructure costs are based on the bandwidth used, not the specific application. The only reason they care about the latter is to price-discriminate between businesses and consumers.
[1] The numbers and units are obviously parameters that a specific ISP needs to tweak based on their actual costs.
[2] Or more sophisticated variations on this theme, like using an hourly basis: e.g. if your usage during the last 720 hours (30 days) exceeds 100 GB, then throttle for a few hours until some high-usage hours fall off the end of the 720-hour window. Or better yet, weight previous usage exponentially.
It's simple and obvious and I'm amazed that Google, of all companies, isn't smart enough to figure this solution out on their own.
From the ISP's point of view, their infrastructure costs are based on the bandwidth used, not the specific application. The only reason they care about the latter is to price-discriminate between businesses and consumers.
[1] The numbers and units are obviously parameters that a specific ISP needs to tweak based on their actual costs.
[2] Or more sophisticated variations on this theme, like using an hourly basis: e.g. if your usage during the last 720 hours (30 days) exceeds 100 GB, then throttle for a few hours until some high-usage hours fall off the end of the 720-hour window. Or better yet, weight previous usage exponentially.