Various example embodiments are disclosed. According to an example embodiment, a technique may include participating in an automatic repeat request (ARQ)-enabled service flow between first and second wireless stations, wherein each transmitted MAC (media access control) protocol data unit (PDU) is partitioned into one or more ARQ-blocks, with each ARQ-block, except a last ARQ block of a MAC PDU, having a fixed size equal to an ARQ-block-size, negotiating a change to the ARQ-block-size for the service flow via a request and response message exchange. In another embodiment, a technique may include transmitting an ARQ block size change request for a service flow from a first wireless station to a second wireless station, the ARQ block size change request including one or more parameters relating to a new ARQ-block-size for the service flow; receiving, at the first wireless station from the second wireless station, an ARQ block size change response for the service flow in response to the transmitting the ARQ block size change request; and implementing the new ARQ-block size for the service flow based on the received ARQ block size change response.