Apparatuses, systems, and methods for transmitting data frames over data networks with varying Interframe Space (IFS) times are disclosed. A system embodiment may comprise a mobile computing device with an integrated wireless networking card. The card may receive a transmission of several data frames. While receiving the several data frames, the networking card may determine that a response will need to be transmitted back to the sending station after the sending station sends the last frame of data. After a short period of delay following the end of the last transmitted frame the card may immediately begin transmitting a preamble of the response, while still demodulating and processing data of the transmitted frames. Upon finishing data processing of the remaining frames, the card may generate the content for the rest of the response, such as a block acknowledgment.