Node authentication and node operation methods within service and access networks in NGN environment

Provided are node authentication and node operation methods within service and access networks for bundle authentication between the service and access networks in a next generation network (NGN). A method of authentication processing of a node (S-CSC-FE/I-CSC-FE (Serving Call Session Control Functional Entity/Interrogating Call Session Control Functional Entity)) within a service network for bundle authentication between service and access networks, the method including: receiving first authentication information about access authentication of a terminal from a first node within the service networks; requesting to receive second authentication information from a second node within the service network based on the first authentication information; and comparing the first authentication information with the second authentication information to authenticate the terminal.