Negative acknowledgment mechanisms

An apparatus for wireless communication, comprising:

• at least one memory comprising computer-executable instructions;
• and
• one or more processors configured to execute the computer-executable instructions and cause the apparatus to:
• output, at a second wireless node, a physical layer (PHY) protocol data unit (PPDU) intended for a first wireless node;
• obtain a frame indicating negative acknowledgment of at least a portion of the PPDU if one or more conditions are met;
• and
• output, for re-transmission, one or more MAC Protocol Data Units (MPDUs) that were contained in the PPDU, after obtaining the frame.

A method for wireless communications at a first wireless node,

• obtaining information indicating transmission, from a second wireless node, of a physical layer (PHY) protocol data unit (PPDU) intended for the first wireless node;
• generating a frame indicating negative acknowledgment of at least a portion of the PPDU if one or more conditions are met;
• and
• outputting the frame to the second wireless node.