This property is similar to the ij.protocol property. The only difference is that it associates a name with the value, thus allowing you to define and use more than one protocol. (See Connect.)
ij.protocol.protocolName=protocolForEnvironment
D:>java -Dij.protocol.derby=jdbc:derby:
-Dij.protocol.emp=jdbc:derby: org.apache.derby.tools.ij
ij version 10.2
ij> Connect 'newDB' protocol derby as new;
ij>