A network cluster is provided herein having a plurality of cluster members. In order to control the admission of client requests sent to the cluster, one member of the cluster is elected “reservation coordinator.” The reservation coordinator runs a reservation algorithm for controlling the distribution of rate capacity across members of the cluster. For example, each member of the cluster may reserve some amount of rate from the coordinator to allow for passing of client requests. To ensure that each member is provided with the appropriate rate capacity, each member of the cluster runs an estimation algorithm to determine whether or not additional rate capacity should be reserved from the reservation coordinator, or released back into the cluster for redistribution. The estimation algorithm is run in real-time and allows the admission control algorithm to adapt to changes in rate distribution.