The SMSOTP authenticator allows you to authenticate user via short messages through WSO2 IS.
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To get started with the authenticator, go to Configuring SMSOTP Authenticator Operations. Once you have completed your configurations, you can perform authentication with the SMSOTP authenticator
To download the authenticator and other artifacts, go to https://store.wso2.com/store/assets/isconnector/smsotp.