Change SSL and TLS Version

This topic describes how to change SSL and TLS version used on the Yeastar S-Series VoIP PBX.


  1. Log in to PBX web interface, go to Settings > System > Security > Service.
  2. In the drop-down list of System Security Level, select a type to change the SSL and TLS version.
    • High Level: The system only supports TLS 1.2 protocol.
      Note: We recommend that you select High Level to ensure secure communication over network.
    • Low Level: The system only supports TLS 1.0, TLS 1.1, TLS 1.2, and SSL 3.0 protocols.
      Note: If users wants to access the PBX via a web browser or a 3-rd party software, which doesn't support TLS 1.2 protocol, select Low Level.
  3. Click Save.


The web browser or the 3rd-party software needs to enable the same version of TLS/SSL before they can access the PBX.