# Comparison of Status mechanisms

## Contenders

- short-lived Credentials (no status)
- Deny-List (CRL, Idenitfier List for JSON/CBOR)
- StatusList (bitarray/bitstring, IETF Token Status List, W3C StatusList 2021)
- OCSP
- OCSP stapling / Status Attestations / Validity VCs / Non-Revocation Token
- Accumulator (e.g. Indy)
- TOTP + Bloom Filter (DynamicSLBloomFilter2023)


## revocation use cases

- important from german eIDAS proposal
- others?

## Evaluation Criteria

- Scalability
- Does the effiency suffer for the issuance or the verifier when adding new elements
- Option for Third Party Hosting/CDN?
- Privacy
- Observability from Issuer (Traceability)
- Observability from Verifier (Profiling)
- Observability from Outsiders
- Complexity
- Algorithm (is it easy to understand?), is the Specification publical available (for free)
- Implementation (is it hard to implement? How many libraries exist to support it?)
- Communication requirements
- during issuance
- during presentation
- Efficency (costs/time, required resources)
- Efficiency for Issuer
- (how many resoures are required to update one credential)
- providing the information
- Efficiency for Holder
- Efficiency for Verifier
- Feature
- Historical data
- Third Party hosting as a privacy feature
- reversible status changes
- Offline capability and Caching
- Scenario Holder is offline
- Scenario Verifier is offline
- Dependancy
- Bound to specific algorithms (e.g. crypto agility)
- Bound to a specific system (DLT)