A transmitting apparatus is provided for transmitting data to a receiving apparatus, the transmitting apparatus comprising: a first network interface configured to transmit data to the receiving apparatus over a first communications path; a transmit buffer forming part of the first network interface, the transmit buffer being configured to store a series of packets of data for transmission over the first communications path; a data compression module configured to compress at least some of the packets of data stored for transmission; a second network interface configured to receive a decompression rate value from the receiving apparatus over a second communications path; and wherein the apparatus is configured to select data packets stored in the transmit buffer for compression based on a compression rate value and a transmission rate value of the transmitting apparatus and a decompression rate value received from the receiving apparatus via the second network interface. A receiving apparatus is also provided.