email2 is compatible with existing email structures. If you are using Microsoft Outlook, Exchange, Zimbra or have a scanning process, archiving system, indexing system or any other perimeter defense in place, the email2 Security Platform will work alongside the existing structure to provide additional security and privacy.
The only difference is that email2 bypasses SMTP and instead uses a secure HTTPS connection for exchanging secure email2 messages, through the use of the Private Email Network platform (acting as a gateway server). That's where the true value proposition resides: we don't replace or interfere with anything. Everything you currently have in place still works the same, including PKI, if you are already using email encryption (using email2 will cause your email client to exchange the encrypted message over HTTPS instead of SMTP).
There are several advantages to this type of architecture, (e.g. accurate tracking, no size limit on attachments, etc.), which cannot be addressed by simple email encryption. And of course, the HTTPS transfer protocol is just as secure as any email encryption available on the market.
//Edited March 2010