Malicious and selfish behavior of node can cause serious threats in delay tolerant network. Thus designing a misbehavior scheme is a great challenge in DTN. The authors propose a trust model on the basis of packet drop level detection. The basic idea of trust model is introducing a periodically available Trusted Authority (TA). TA launches probabilistic detection for the target node and judges it by collecting the forwarding history. It reduces verification cost incurred by routing evidence phase. It also allows trusted authority to launch the misbehavior detection at a certain probability. It makes a proper communication between the sink node and the receiving node and transfer data over multiple router.