In this paper, we proposed scheme that we use a difference of timestamp in time in Ubiquitous environments as we use the Diffie-Hellman method that OTP was applied to when it deliver a key between nodes, and can detect a malicious node at these papers. Existing methods attempted the malicious node detection in the ways that used correct synchronization or directed antenna in time. We propose an intermediate malicious node detection way at these papers without an directed antenna addition or the Trusted Third Party (TTP) as we apply the OTP which used timestamp to a Diffie-Hellman method, and we verify safety regarding this. A way to propose at these papers is easily the way how application is possible in Ubiquitous environment.