U2F (Universal 2nd Factor) is an MFA Protocol introduced by FIDO. It is one of the fastest growing MFA protocol adopted due to ease of use and advanced security it offers. This series of blogs mainly talks about how this protocol works and gives tips on implementing this protocol on any website.
U2F solved one of the major pain point related to MFA, usability. There isn't any App or hardware token to generate a pin and input it, all that needs to be done is touch a security key. And vendors (such as Yubico) have developed keys which could be used with USB (Type A or C), Bluetooth or NFC which make it even more comfortable to adapt.
Security protocols used by U2F keys are another reason for such fast adaptation. It uses public key cryptograph, to make sure every transaction is encrypted between all parties involved. Upon that, the source of every request is validated to prevent any phishing attacks.
But U2F still has some way to go as not all browsers support, notable exception being Safari. And mobile use of U2F also have some complications that need to be solved. And there are some protocal details (such as the use of attestation) that havent been accepted by all U2F Vendors.
In the next part of the series, I'll go into details about how the protocol works and the data that get exchanged between all the parties involved.