Accordingly, the embodiments herein provide a method for authentication of an IAB node by an IAB-donor node in a wireless network. The method includes obtaining an IAB authorization information of the IAB node from one of an Access and Mobility Management Function (AMF) and a Mobility Management Entity (MME) of the wireless network, determining whether the IAB authorization information of the IAB node indicates the IAB node is authorized, and allocating a unique identity/parameter to the IAB node during an IAB-Mobile Termination (MT) setup and/or Backhaul Radio Link Control (RLC) channel establishment and/or Routing update phase. Further, the method includes storing the unique identity/parameter in a user equipment (UE)-context, which is used to identify the UE-context during an IAB-Distributed Unit (DU) part setup for authorization check and/or authentication.