Can anyone explain Googles S/MIME feature in plain English :)

[uke]

I would like to have teachers emails in G Suite be encrypted just because teachers are probably sending data which should be encrypted without thinking about it. We only have a few licences in the school for Egress and it would be great to just know everyone had the option of encrypted email.

 

I tried reading Googles info about S/MIME but got confused. Does it only work if certain conditions are met by both email sender and recipient? As its very new I wondered if anyone knew of a good guide to get working in schools or if it can be explained?

 

Or, is it not really proper encryption and I have misunderstood what was being offered?

 

Thank you