1 ) A method of allocating a network resource between a plurality of network applications, comprising: obtaining, for each of said plurality of network applications, parameters defining a quality function indicative of quality of service obtainable as a function of the amount of said network resource available to that network application, said parameters comprising: (i) a first measure indicative of a target amount of said network resource that said application requires in order for said application to perform at a level substantially at or above a first predetermined performance level; (ii) a second measure indicative of a threshold amount of said network resource that said application requires in order for said application to perform at a level substantially at or above a second predetermined performance level, said second predetermined performance level being lower than said first predetermined performance level; (iii) a performance change rate measure indicative of a rate of change of a predetermined measure of performance of said application with respect to amount of said network resource allocated to said application; then allocating proportions of said network resource respectively to each of said network applications in such a way as to optimise a predetermined function dependent on said first measures, said second measures and said performance change rate measures obtained in respect of each of said plurality of network applications.