First, we introduced Office 365 Message Encryption – i.e. the ability send public secured emails to recipients without requiring any add-ins or additional technologies on either the sender or recipient’s computers. This service is available at no additional cost to Office 365 E3/E4 subscribers.
Now, we’re introducing S/MIME as well for Office 365, enabling public key encryption & digital signing of messaging data, and again, at no additional cost to Office 365 E3/E4 subscribers.
Recently, we published a blog post that outlines how strongly committed we are to protecting our customers’ information. A key aspect of our strategy is to expand encryption across all our services. Earlier this month, we announced Office 365 Message Encryption, a new service that allows you to send encrypted mail to anyone. As part of our ongoing focus on encryption, we announced yesterday that we’re bringing S/MIME capability to Office 365 and Exchange Server 2013 Service Pack 1. With this release, customers will have S/MIME support across Outlook, Outlook Web App (OWA), and Exchange ActiveSync clients. S/MIME for Outlook and EAS is already available on Exchange Online and S/MIME on OWA is being rolled out and is expected to be completed by early April.
S/MIME (Secure/Multipurpose Internet Mail Extensions) is a standard for public key encryption and digital signing of MIME data, and it is defined in a number of Requests for Comments (RFCs): 3369, 3370, 3850, and 3851. S/MIME allows a user to: (1) encrypt an email and (2) digitally sign an email, and thus provides cryptographic security services such as authentication, message integrity, and non-repudiation of origin (using digital signatures). It also helps enhance privacy and data security (using encryption) for electronic messaging. You can learn more about S/MIME in this technet article.
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