The countersignature in the engine means that there are multiple people handling the current running node, or it can be said that there are multiple handling tasks in the current node. These tasks can be run in two situations. One is to handle them in sequence, that is, serial countersignature; the other is to handle them at the same time, that is, parallel countersignature. Both serial countersignature and parallel countersignature can set the pass rate. The pass rate in serial countersignature is set according to the number of people who pass. When the number of people who pass is reached, the node is completed and enters the next node. The pass rate in parallel countersignature is set according to the percentage of the number of people. When the percentage of the number of people handling the task is reached to the total number of people, the node is completed. The following example explains the countersignature node.