Ad-hoc networks generally play a vital role in emerging technologies. The limited communication and computation resources, the unguaranteed connectivity to trusted authorities make known security solutions for wired networks. A novel Tiered Authentication scheme for Multicast traffic (TAM) has large scale of ad-hoc networks. Nodes are grouped into the cluster. Cross-cluster multicast traffic includes a Message Authentication Code (MAC) that is based on set of keys. Each cluster uses unique subset of keys. TAM is combination of secret information asymmetry and the time information asymmetry for inter cluster and intra cluster networks. The topologies used are flat, spanning tree, balanced tree to reduce bandwidth overhead and delivery delay. These topologies are compared for numerical and analytical results that demonstrate the advantage of TAM.