!!! Overview [{$pagename}] is a [RFC] describing [SMTP] [Security] via Opportunistic [DNS-Based Authentication of Named Entities] ([DANE]) [Transport Layer Security] ([TLS]) [We refer you to the full text|RFC:7672|target='_blank'].[{$pagename}] implementations are protected from [StartTLS] Downgrade [Attack]. !! More Information There might be more information for this subject on one of the following: [{ReferringPagesPlugin before='*' after='\n' }]