# Authentication
Source: https://nordvec.com/docs/guides/authentication#key-classes

## Key classes [#key-classes]

A key is one of two classes, and its prefix says which:

| Class | Prefix | For |
| --- | --- | --- |
| Client | `nv_eu_live_` | Reading: search, list and fetch documents, quota, audit trail |
| Indexing | `nv_eu_idx_` | Writing: push, delete and re-permission documents, check ingestion |