# How do you add authentication to your request?
The authentication feature has two options:
1. Email OTP (One Time Password)
2. Access code
Check out how each authentication type works:
OTP (EMAIL/SMS)
*A six-digit verification code auto-generated by the Evia Sign.* You have the option of sending this OTP to the signatory's phone number, the email address, or both.
Access code
The signature requester *can specify a verification code of their choice. In this case, the verification code will be directly communicated to the signatory(s).*
Follow the detailed steps below to set up authentication:
* Select the signatory to whom you want to set up the authentication option and enable authentication by clicking the toggle switch to activate the feature.
* Select one of the authentication options.
* This action will assure that an email OTP or an access code is always requested from the signatory when proceeding to open and sign the document.
{% hint style="info" %}
In the case of multiple signatories, follow the same procedure.
{% endhint %}
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