Background & Objective:: In past few years, Cognitive Radio (CR) paradigm has emerged as a promising and revolutionary solution to avoid problems of spectrum paucity and inefficiency in spectrum usage. Efficiently utilization of the spectrum offers high network performance. CRs are proficient to identify and adopt the unused spectrum in order to allow secondary users to occupy it without interfering the primary user’s activity. Cognitive Internet on Things (CIoT) is an integration of several technologies and communication solutions which can be effectively realized as Cognitive Radio Adhoc Networks (CRAHN). In CRANH, on-demand routing protocols are the best suitable protocols due to their dynamic feature of available un-utilized channel/spectrum selection. Methods: Here, firstly, Ad-Hoc On-Demand Distance Vector (AODV) routing protocol has been modified and further evaluated to address route selection challenges in CIoT framework. Secondly, the effects on network performance under network layer routing attacks (i.e. blackhole attack, byzantine attack and flooding attacks) are evaluated. Conclusion: The simulations results demonstrate network performance increase with more channels and degrade differently under attacks.