1. A method comprising determining a fragmentation threshold value and a data rate value for packet transmission frames to be transmitted from a transmitting node to a receiving node, wherein the determined data rate value is a first data rate value at least when a signal-to-noise (SNR) value of packet transmissions received by the receiving node from the transmitting node is a first SNR value and is a second data rate value larger than the first data rate value when said SNR value of packet transmissions received by the receiving node from the transmitting node is larger than said first SNR value, wherein the determined fragmentation threshold value is a first fragmentation threshold value at least when said SNR value of packet transmissions received by the receiving node from the transmitting node is a particular SNR value and is a second, larger fragmentation threshold value when said SNR value of packet transmissions received by the receiving node from the transmitting node is larger than said particular SNR value, and wherein the first and second fragmentation threshold values are based on the determined data rate value.