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Look up a field202 definitions, formats and value codesUnderstand a message11 message types and their field inventoriesBuild a required-field checklistSet channel and category in the explorerCompare documentsInspect changes and understand version coverage
Message reference
- AReqAuthentication Request3DS Server → DS → ACS
- AResAuthentication ResponseACS → DS → 3DS Server
- CReqChallenge Request3DS SDK/Browser → ACS
- CResChallenge ResponseACS → 3DS SDK/Browser
- RReqResults RequestACS → DS → 3DS Server
- RResResults Response3DS Server → DS → ACS
- PReqPreparation Request3DS Server → DS
- PResPreparation ResponseDS → 3DS Server
- OReqOperation RequestDS → 3DS Server/ACS
- OResOperation Response3DS Server/ACS → DS
- ErroError MessageAny → Any
Common field lookups
Using the specification
- How to find required AReq fields
- How to compare EMV 3DS versions
- Sources, review process and coverage limits
What this reference covers
The field reference uses the Protocol and Core Functions Specification 2.3.1.1 (2023-05-30). Introduction tags describe selected historical changes; they are not complete snapshots of older specifications. Selected FAQ qualifications are included, with their scope shown alongside each field.
For official specifications, current releases and bulletins, visit EMVCo’s 3-D Secure documentation. This service is an independent aid to reading those documents.