In this paper, we propose a new method for fast and efficient detection of communication protocol errors with less memory requirements and processing time when there exists an excess/deficiency of definition or deadlock in signal transmission/reception. Practically, a new method of protocol validation is presented where the protocol errors are detected by dividing the protocol inspection into two stages: one is inspection centered on the operations of each process and the second is inspection of all process operations at the same time. The characteristic of this method of validation is that in the former stage the excess/deficiency of transmission/reception is detected without enumerating the states of the whole system and in the second stage, deadlock is detected by enumerating the minimum number of system states. As a result, when the number of processes is large, the number of system states to be enumerated, can be greatly decreased as compared to the conventional methods. To evaluate the proposed method of protocol validation we present application results of various protocol examples. We show that memory requirements and processing time are greatly reduced and large-scale protocols with large number of processes which could not be fully inspected by the conventional methods, can also be validated completely.