The name of the group for the mapping represented by
this row. This is in addition to the 'vacmGroupName'
mapped in the 'vacmSecurityToGroupTable'. For example
a user principal represented by 'securityName' maps
to a group represented by 'cvacmSecurityGrpName' under
a security model represented by 'securityModel'.
This groupName is used as index into the
'vacmAccessTable' to select an access control policy.
However, a value in this table does not imply that an
instance with the value exists in table 'vacmAccesTable'.