Investigation of overload control algorithms for SCPs in the intelligent network

All nodes in the intelligent network (IN) must have an overload control mechanism which protects the node by rejecting calls when the load on the node is too high. Two examples of IN nodes are the service control point (SCP), which contains the service logic that is used to provide IN services, and the service switching point (SSP) which detects requests for IN services. The authors investigate overload control mechanisms for the SCPs. To achieve an efficient control, the rejecting mechanisms are placed in the SSPs instead of the SCPs. It is stressed that the algorithms should be both efficient and show fairness among a number of SSPs logically connected to the SCP. The results show that, to have fairness among the SSPs, the SCPs must control the acceptance rate