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Constraint 2: When the value is separated in three four parts, the separating character being a dot (.), the first part must reference a value in Switch.name. The second part must reference a value in EthernetPort.name where EthernetPort is a child element to the device referenced by part 1. The third part +fourth parts must be either EI.Tx (Egress Interface.Transmitter) OR II.Rx (Ingress Interface.Receiver).
Constraint 3: The EthernetPort that is referenced must be connected.
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