Tokenisation versus pseudonymisation
The difference between a technical mechanism and a privacy classification.
In customer conversations the two words get used interchangeably, and that causes real confusion. One names what a system does, the other names what a dataset is. A security engineer asks about tokenisation; a data protection officer asks about pseudonymisation. They are looking at the same architecture through different vocabularies.
Two vocabularies, one architecture
Tokenisation is the technical method. Replace +90 532 000 00 01 with PHONE_qzvtrn before the request leaves; hold the mapping in a separately secured store; restore inside the perimeter.
Pseudonymisation is the classification. Data that can no longer be attributed to a person without additional information that is kept separately and protected, the condition GDPR Article 4(5) and KVKK describe.
The connective tissue is the “additional information” clause. Pseudonymised data is data whose re-identification key exists but is held separately, under protection. In Salus that additional information is exactly the token mapping, and its separation is architectural: the vault lives in your PostgreSQL under your key, while the external provider receives tokens only, with no access path to the mapping.
The three concepts side by side
| Concept | Meaning | In Salus |
|---|---|---|
| Tokenisation | Replaces values with generated tokens | The mechanism used before the provider call |
| Pseudonymisation | Attribution needs separate additional information | May describe the resulting dataset, depending on the legal and operational context |
| Anonymisation | Re-identification is no longer reasonably possible | Not the objective of reversible restoration. See Anonymisation |
What Salus does and does not claim
Salus provides the technical controls a pseudonymisation posture depends on: detection before egress, typed reversible tokens, a separately secured mapping under your key, permissioned and logged restoration, and tenant isolation. What Salus does not do is declare your processing pseudonymised. That depends on the complete context of the deployment: token scope, access controls, what other data the recipient holds, and the legal analysis of the processing operation.
Not legal advice. This page explains technical concepts. Whether a specific processing operation qualifies as pseudonymisation is a determination for your organisation’s counsel.
All example values in this documentation are synthetic.