| Create Bitstring Status List | Create a Bitstring Status List on cheqd as a DID-Linked Resource |
| Update Bitstring Status List | Update a Bitstring Status List to revoke/suspend credentials |
| Check Bitstring Status List | Check whether a specified indices is revoked, suspended, unsuspended or valid |
| Search Bitstring Status List | Search for specific entries in the Status List, traversing its history |
The Bitstring Status List supported in cheqd Studio utilise bitstrings to represent whether a Verifiable Credential has been suspended/revoked or not. A bitstring can be thought of as a long list of 1s and 0s, where, if the binary value of the position in the list is 1 (one), the verifiable credential is revoked, if it is 0 (zero) it is not revoked.
Figure 1: Graphic showing the Bitstring Status List bitstring
Each issued Credential correlates with a position and index on the bitstring, so that a verifier will be able to correlate the value within the Credential against the public bitstring to ascertain whether the Credential has been revoked or not, using a validate algorithm as well as a bitstring expansion algorithm.
The issuer keeps a bitstring list of all Verifiable Credentials it has issued. The Status List is usually published by the issuer in the format of its own Verifiable Credential. This Verifiable Credential is generally hosted publicly on a centralised server or domain to enable third-party read-access.
cheqd stores each Status List and subsequent entries on-ledger as DID-Linked Resource versions. This has notable benefits, including the provenance, legitimacy and security of the Status List. For a full list of benefits, see the context for creating DID-Linked Resources.