anonymization

Anonymization (intermediate plugin)

The plugin performs IPv4/IPv6 address anonymization of all flow records. There are two available methods that could be applied on IP addresses, CryptoPAN and address truncation.

To identify IPFIX fields of a record to modify, the plugin uses a type of an Information Element linked to each field. Thus, any record field with known corresponding Information Element and type is always automatically anonymized. Enterprise-specific Information Elements are supported too.

Example configuration

<intermediate>
    <name>Flow anonymization</name>
    <plugin>anonymization</plugin>
    <params>
        <type>CryptoPAn</type>
        <key>0123456789abcdefghijklmnopqrstuv</key>
    </params>
</intermediate>

Parameters

type:

Type of anonymization method. The string is case insensitive. CryptoPAn: Cryptography-based sanitization and prefix-preserving method. The mapping from original IP addresses to anonymized IP addresses is one-to-one and if two original IP addresses share a k-bit prefix, their anonymized mappings will also share a k-bit prefix. Be aware that this cryptography method is very demanding and can limit throughput of the collector. Truncation: This method keeps the top part and erases the bottom part of an IP address. Compared to the CryptoPAn method, it is considerably faster, however, mapping from the original to anonymized IP address is many-to-one. For example the IPv4 address "1.2.3.4" is mapped to the address "1.2.0.0".

key:

Optional cryptography key for CryptoPAn anonymization. The length of the string must be exactly 32 bytes. If the key is not specified, a random one is generated during the initialization.

Notes

Usually all common IP addresses are automatically anonymized. However, if an IPFIX field is not, make sure that the particular Information Element is defined among other definitions provided by libfds library. Mainly in case of Enterprise-Specific Information Elements, there is a chance that the definitions are missing. See the documentation of the library, for help to easily add extra definitions in few steps.