The identity will be substituted for the target address when the I-CSCF performs a second location query to the HSS and SLF when unallocated numbers have been identified. This parameter must be configured before the CscfUnallocatedRoutingEnabled can be set to true. Before CscfUnallocatedRoutingEnabled can be set to false the parameter must have a different value than "empty".
This is the key attribute of the CscfUnallocatedRoutingContainer class. One instance of the CscfUnallocatedRoutingContainer with the key cscfUnallocatedRoutingKey=0 is created at startup. This instance cannot be deleted. No other instances can be created of this class.