Described herein is a method of controlling calls for packet switched networks, each network including at least two local area networks (50, 60) and a connecting network (70). The method comprises the steps of determining an 5 acceptable packet loss rate for a call to be established between two of the local area networks, comparing actual packet loss rate to the acceptable packet loss rate, and dropping the call if the actual packet loss rate is greater than the acceptable packet loss rate. determining for how long a period the actual packet loss rate has been happening and utilising that period in deciding to drop the call. A recorded announcement may be played when the call is to be dropped. Alternatively, the priority of the transmission of the continuous stream of data can be changed when the actual packet loss rate is not acceptable and the above steps are repeated. Ideally, data relating to dropped calls is stored for future one.