The value of tmnxMcPathOperChlIngLastHighest indicates the value of the
multicast bandwidth that is currently being accounted for the channel
on its forwarding path on the MDA. The value is computed based on
periodic polling of statistics and represents the last highest
bandwidth value since the bandwidth update timer for the channel was
(re)started. This field inherits the value of
tmnxMcPathOperChlIngSecHighest when the bandwidth update timer expires.
This indicates that the bandwidth of the channel is lower than that
recorded when the bandwidth update timer was last started. Before the
bandwidth update timer expires, if the polled value of the bandwidth is
greater than or equal to the current value, the current value is
updated to the new value if necessary and the bandwidth update timer
is restarted.