This value is the current operational status (e.g. up, down, link-down, or sfp-not-present) of this internal backplane link, as opposed to its administratively configured state. It matters on the internal Ethernet link that carries a blade's traffic from the chassis I/O Module up to a Fabric Interconnect over the backplane because this is the field that actually reflects whether traffic can pass right now, and it is what an admin checks first after confirming adminState is enabled. An operState of link-down on this backplane link while adminState remains enabled would send an admin to check the physical seating of the IOM in chassis 1, slot 1, rather than any configuration setting.