Applied Controls Inc has worked with a multitude of customers across various industries to help them utilize their S7-1200 PLCs secure emailing and data log attaching functionality! 

With the provided TMAIL_C instruction in TIA Portal the implementation of this functionality was seamless.

Before firmware version 4.4 the S7-1200 required an additional ethernet communication module to send SMTP (simple mail transfer protocol) over TLS (transport layer security) and attaching data log files was not possible. TLS is the successor to SSL (secure sockets layer) and the purpose of this protocol is to provide communications security over a computer network! This update makes the S7-1200 a simple, powerful, and cost-effective industrial emailing solution for customers with high local area network security requirements.

Native SMTP over TLS is a very important feature because popular email servers such as GMAIL and Outlook require the email sender to use TLS.

The flagship Siemens S7-1500 PLCs are also capable of secure, native emailing and data log attachments as of firmware version 2.5!