A Basic Worklist Management SCP shall support matching based on values of all Required Matching Key Attributes of the C-FIND request. Multiple entities may match a given value for a Required Key.
If an SCP manages an entity with an unknown Attribute value (i.e. zero length), the unknown value shall fail to match any Matching Key value.
Notes: 1. Even though there is no means to perform matching on such entities, they may be queried as a Return Key Attribute using a C-FIND request with a zero length value (universal match) or by a single wildcard (wildcard match).
2. An SCU may choose to supply any subset of Required Matching Key Attributes.