Correct me if I'm wrong but I think you're confusing U2F (the open standard) with a second factor of authentication (the thing) U2F has traditionally been dist

Correct me if I'm wrong but I think you're confusing U2F (the open standard) with a second factor of authentication (the thing) U2F has traditionally been distributed in the form of physical tokens. It's an open standard compared to Duo's. (The rest is just copied off another comment I made down this thread) But there in lies the difference. With Krypton, the company doesn't own your keys, you do. It's like Fiat vs Bitcoin.. only there's literally no difference in experience. That's why Krypton is better. It works everywhere U2F (an open spec) is supported, while the proprietary company solution is supported where the company has partnered