Data Loss Prevention: Keeping Sensitive Information From Leaving Your Network

What Is Data Loss Prevention

Data Loss Prevention (DLP) is a set of technologies and policies that detect and prevent unauthorized transmission of sensitive data outside your organization. DLP systems monitor data in use (on endpoints), data in motion (on the network), and data at rest (in storage) to enforce security policies that prevent accidental or intentional data leaks.

Classifying Your Data

Effective DLP starts with understanding what data you have and how sensitive it is. Classify data into categories: public, internal, confidential, and restricted. Use automated classification tools that scan for patterns like credit card numbers, Social Security numbers, health records, and proprietary source code. Apply labels that follow the data wherever it goes. You cannot protect what you have not identified.

Implementing DLP Policies

Start with monitoring mode to understand how sensitive data flows through your organization before blocking anything. Common policies include: prevent email attachments containing credit card numbers, block uploads of source code to personal cloud storage, alert when sensitive files are copied to USB drives, and prevent printing of documents labeled as restricted. Tune policies based on monitoring data to avoid disrupting legitimate business processes.

Insider Threat Considerations

DLP is not just about preventing external data theft - it also addresses insider threats. Disgruntled employees, contractors with excessive access, and careless handling of sensitive data are all risks. Monitor for unusual patterns like downloading large volumes of files, accessing data outside normal working hours, or copying data immediately before a scheduled departure. True Protection's DLP features integrate with endpoint monitoring to detect and respond to data exfiltration attempts in real time.