The expansion of wireless applications in dense environments raises many technical issues. The 802 standards need to adapt and enhance the network quality by developing new technologies. The block acknowledgment (BA) mechanism was introduced in the IEEE 802.11e standard to improve medium access control (MAC) efficiency. It requires the exchange of many control frames to establish a session with each user, which turns into an issue for networks in dense environments as it causes increased overhead and latency. This paper deals with the optimization of the BA session management procedure. We propose a modified block acknowledgment session control mechanism which reduces the overhead and latency compared to the original one.