Yealink SIP-T4X Administration Manual page 196

2) Enter the password for authentication in the MD5 Password field.
b) If you select EAP-TLS:
1) Enter the user name for authentication in the Identity field.
2) Leave the MD5 Password field blank.
3) In the CA Certificates field, click Browse to locate the desired CA certificate
(*.pem,*.crt, *.cer or *.der) from your local system.
4) In the Device Certificates field, click Browse to locate the desired client
certificate (*.pem or *.cer) from your local system.
Configuring Advanced Features
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