This attribute counts the number of times the IWF RLP entity is
busy (that is it is in Asynchronous Balanced Mode (ABM) and is
not ready to receive Information frames). When the network side
introduces flow control towards the mobile and a Receive Not
Ready (RNR) is sent to the mobile to stop the mobile from sending
any more data frames. A Receive Ready (RR) is sent to the mobile
when the RLP entity is ready to receive data. The counter wraps
when it exceeds the maximum value.