A transmission apparatus includes a memory adapted to store data to be transmitted, a transmission unit adapted to transmit, via a network, the data to be transmitted to a destination apparatus connected to the network, and a first rate controller adapted to control a first rate such that when the data to be transmitted having a size greater than the capacity of a transmission buffer of the transmission unit is transferred from the memory to the transmission buffer, the first rate at which the data is transferred from the memory to the transmission buffer is controlled to restrict the amount of data to be transmitted stored in the transmission buffer.