Trend Micro Email Encryption is a virtual appliance that can be installed on a physical or virtual server. It is an application-layer encryption tool. The product, while capable of being used as an independent device, works best in the context of a full content management system. Trend Micro Email Encryption has several deployment options - from inline to part of a complementary content management tool. The encryption algorithm is AES-256, but message encapsulation is identity-based and Trend Micro proprietary. No certificates are required, and users register with Trend for authentication.

Internal use requires no client-side software. For web delivery, no recipient client is required, but there is an add-in for Outlook. If the recipient's content filter blocks attachments such as those used by the product, Trend can provide characteristics that will permit whitelisting. Management is done through a web interface.
Initial setup is straightforward, and there is a helper that can be set up to ensure PCI compliance. Specific content can trigger encryption, as can a variety of other conditions. Again, Trend recommends that the product be used in the context of a complete content management package. The granularity of policy management within the product by itself is less than perfect.

Support is excellent, with many options, and the website is well-stocked with information. Documentation too is excellent with many network diagrams and screen shots.

The product can be quite expensive - nearly $50,000 for the 5,000-user example, and that is for the email encryption product only - and the emphasis on incorporating it in a full content management package seemed to us to discourage standalone implementation. The few limitations on functionality, such as policy granularity, confirmed this impression.