This attribute counts the number of Channel Mode Modify (CMM)
requests initiated by the IWF.
For transparent fax calls, the transmission speed is determined by
the two fax machines at call setup. The speed may change during
the transmission to satisfy the T.30 protocol. The CMM request is
used by the GSM IWF to request that the T.30 requested speed
change can be propagated throughout the network. The counter
wraps when it exceeds the maximum value.