Switch#show int tran
Transceiver monitoring is disabled for all interfaces.

If device is externally calibrated, only calibrated values are printed.
++ : high alarm, +  : high warning, -  : low warning, -- : low alarm.
NA or N/A:not applicable,Tx:transmit，Rx:receive.
mA: milliamperes, dBm: decibels (milliwatts).

                                         Optical   Optical
          Temperature  Voltage  Current  TxPower   RxPower
Port      (Celsius)    (Volts) （mA）    (dBm）    (dBm)
------------------------------------------------------------
Twe1/0/1  36.8         3.23     38.7     -2.2      -1.5
Twe1/0/2  32.6         3.31     33.6     -1.1      -1.9