The XMEGA USB supports ping-pong buffering. USB communication without ping-pong buffering uses a single memory bank for storing the data to transfer. If this data bank is full, the MCU will respond with a NAK (Negative-Acknowledge) message. Receiving a NAK, the host will wait and retry the transfer later; it will continue to retry the transfer until it is successful. Ping-pong buffering eliminates this problem. It uses two memory banks for data transfer. When one of the memory banks is full, the host can transfer data to the other bank. Alternating between two buffers gives the MCU more time to process data and reduces the likelihood of the host receiving a NAK message. Ping-pong buffering can be used for both sending and receiving data and results in increased bandwidth. In particular, applications using Isochronous transfer, such as video or audio streaming, will benefit from ping-pong buffering.