This is a description of the latest network based authenticators on the market going into 2021.
ZenKey – AT&T, T-Mobile and Verizon have collaborated together to create and launch ZenKey. ZenKey is a network based authentication solution that leverages the carrier network and SIM card details to authenticate and provide identity verification for web and mobile applications. ZenKey is differentiated because it relies on the carriers network and device data including the SIM card. It is difficult for users and data to be hacked using a compromised username/password due to backend authentication and an attempted malicious SIM swap can be detected and used to alert the relying parties.