The Websense Data Security SMTP agent is installed on a Data Security server or on another Windows server equipped with Microsoft Internet Information Services (IIS) v6. The server must be running Windows Server 2003 standard R2 edition (32- or 64-bit).
It receives all outbound email from the mail server and forwards it to a Websense Data Security Policy Engine. The SMTP agent then receives the analyzed email back from the policy engine. Depending on the analysis, SMTP agent blocks the email or forwards it to the mail gateway. When installed on the Data Security Management server or supplemental Data Security server, the SMTP agent uses the local policy engine of those servers to analyze email, unless load balancing has been configured, in which case it uses the specified policy engine. The SMTP agent supports permit, block, and encrypt actions.
Websense recommends you use the SMTP agent whenever you want the ability to block SMTP traffic in a production environment. (If you need only monitor SMTP traffic, the protector may be a better choice for you.)
To use the SMTP agent, you need to configure your corporate email server to route email to it. (The agent becomes a MTA, accepting responsibility for delivery of mail.)
When the agent is installed on a Data Security server, the SMTP traffic is analyzed by the local policy engine. When it is installed as a stand-alone agent, email messages that are sent to the agent are sent to a Data Security server for analysis (whichever server the SMTP agent is registered with). You can configure Websense Data Security to block or quarantine flagged messages.
If an SMTP email transaction was blocked or quarantined, the administrator responsible for handling this incident can release this incident to those recipients originally blocked from receiving the content.
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