The current operational state of the interface. testing - indicates that no operational packets can be passed. up - normal operation down-L2 - down due to a level 2 failure dowm-modem - down due to modem control signals - (Token Ring - transmitting beacon frames or rx beaconing, signal loss) down-other - down for some other reason - (Token Ring - no status yet received, i.e. unknown status) up-blocktx - normal; but Tiger received a flow control signal preventing it from sending data up-preventrx - normal; but Tiger sent a flow control signal to stop the other end from sending data up-bothflow - normal; but Tiger received a flow control signal preventing it from sending data AND sent a flow control signal to stop the other end from sending data cts-failure - RTS was requested, but CTS never came (probably detected via poll timeout) dcd-failure - DCD dropped while receiving data, OR - unable to poll because other ends is still transmitting (polled protocols only). hardware-failure - missing FPGA (Token Ring: PCMCIA card missing) up-isolated - (Token Ring: Single station on the ring)