Administratively desired operational status of the port. For the
actual operational status, please see the related object
nbsCmmcPortEnableOper.
The value notSupported (1) indicates that the user has no ability to
disable the transceiver.
Users may set this value to disable (2) to turn off the port's
transceiver so that no traffic will flow through this port.
For traffic to be sent and received as normal, this object should be
set to enable (3).
The value auto (4) has been deprecated - older Agents might report
it, and Managers may attempt to set it, but newer agents will
neither report nor accept this value.