Privacy Enhanced Filter (PEF)

The Privacy Enhanced Filter (PEF) is as a research project to remove privacy-sensitive information from network traffic as far as possible. This filter facilitates detection and prevention without endangering privacy. A good comparison is Google Street View, where individuals and number plates are anonymised but the road, environment and obstacles remain visible.

How does the Privacy Enhanced Filter work?

PEF removes privacy-sensitive information from network traffic. As a result, privacy-sensitive data such as names and IP addresses are removed from network traffic before it is processed by a firewall/IDS/SIEM. Together with the Netherlands Forensic Institute (NFI), the NCSC has conducted a research project entitled Privacy Enhanced Filtering. Part of this project was delivering a proof-of-concept implementation of an anonymisation filter for network traffic, in particular for DNS traffic.

What is the impact of the Privacy Enhanced Filter?

Large amounts of data containing privacy-sensitive information are used for monitoring detecting network traffic. Network traffic can comprise sensitive information such as personal data, which can make its processing and/or sharing legally/ethically complicated.

Filtering out these data in advance makes the processing and sharing of network traffic more accessible and quicker. As a result, it becomes easier to share and process information during a security incident.

What does this mean for my organisation?

Together with the NFI, the NCSC has developed a proof of concept and made it available to the public. Organisations can download the software from GitHub under an Apache open-source licence. More information? Jump to the news item. Would you like to use the software? The software can be downloaded from GitHub.

What does the NCSC do?

The NCSC has created this application in close cooperation with the Netherlands Forensic Institute and with funding from the NCTV Secure through Innovation programme. Its research was conducted with a sounding board group in which the NCSC, the NFI, SURFnet, the Ministry of Defence, ING and the Police were represented.