If we consider a 802.11 ac network, how many time, at most, can a Block Acknowledgement Request be retransmitted if it is not received at first?
I'm running simulations in the ns-3 simulator, and I observe some situation where this BAR is resent up to 10 times (so, a total of 11 transmissions) by the Access Point over the course of 1.8 second, effectively stalling the transmission on the corresponding link.
In the standard, one can read:
« If there is no response (i.e., neither a Basic BlockAck frame nor an Ack frame) to the Basic BlockAckReq frame, the originator may retransmit the Basic BlockAckReq frame within the current TXOP or SP (if time permits) or within a subsequent TXOP or SP. MSDUs that are sent using the block ack mechanism are not subject to retry limits but only to MSDU lifetime. […] The Basic BlockAckReq frame shall be discarded if all MSDUs referenced by this frame have been discarded from the transmit buffer due to the expiration of their lifetime limit. »
Does this mean, by default, a Basic BlockAckReq can be retransmitted as long as at least one of the MSDU referenced by this frame is valid?