Entity Service - v1.15.0¶
The Entity Service allows two organizations to carry out private record linkage — finding matching records of entities between their respective datasets without disclosing personally identifiable information.
Overview¶
The Entity Service is based on the concept of Anonymous Linking Codes (ALC). These can be seen as bit-arrays representing an entity, with the property that the similarity of the bits of two ALCs reflect the similarity of the corresponding entities.
An anonymous linking code that has been shown to produce good results and is widely used in practice is the so called *Cryptographic Longterm Key*, or CLK for short.
Note
From now on, we will use CLK exclusively instead of ALC, as our reference implementation of the private record linkage process uses CLK as anonymous linking code. The Entity Service is however not limited to CLKs.
Private record linkage - using the Entity Service - is a two stage process:
- First, each party locally encodes their entities’ data (e.g. using the
clkhash tool to produce
CLKs
, using blocklib to group similar entities into subgroups). TheseCLKs
are then uploaded to the service. All these tasks can be conveniently initiated by the anonlink-client tool. - The service then calculates the similarity between entities, using the probabilistic matching library anonlink. Depending on configuration, the output is returned as a mapping, permutations and mask, or similarity scores.