Reducing overload conditions of a node of communication system comprises storing one or more sets of overload range values, where each set represents a range of used capacity of a component of the node. A rejection proportion value is stored in association with each of the sets of overload range values. Messages arrive at the node and are processed by the node. The current processing load or saturation level of the node is continuously measured in real time. The current saturation level is associated with one of the overload ranges. The node rejects a number of messages equal to the rejection proportion value that is associated with the overload range that corresponds to the current saturation level. In an embodiment, only call initialization messages, such as call setup messages or initial address messages, are rejected. The node may be a call processor in a telecommunication network, such as a universal protocol converter.