Consistent Anonymization with Redis

The consistent anonymization feature in Philter ensures that filtered values are anonymized consistently across documents or contexts. When Philter is deployed in a cluster and is using consistent anonymization across contexts, a Redis cache is required. The cache stores the anonymized values so that all instances of Philter have access to the values.

The Redis cache will contain PHI. It is important to prepare your Redis cache such that it can contain PHI.

Enabling Consistent Anonymization

To enable consistent anonymization in Philter set the following property in Philter's configuration:

consistent.anonymization=true
consistent.anonymization.scope=context

Configuring Redis Cache

To enable Philter to use the Redis cache, set the following options in Philter's configuration:

anonymization.cache.service=redis
anonymization.cache.service.host=127.0.0.1
anonymization.cache.service.port=6379
anonymization.cache.service.ssl=true

Replace 127.0.0.1 with the IP address or host name of your Redis cache.

If you are using Redis on AWS ElastiCache see ElastiCache for Redis In-Transit Encryption (TLS) for information on using in-transit encryption.

Restart Philter

After starting (or restarting) Philter, Philter will use the Redis cache for consistent anonymization across contexts. You can restart Philter with the command:

sudo systemctl restart philter.service