Internet Protocol (IP) multicasting is a method for one-to-many and many-to-many communication between hosts in an IP network. This communication happens in a real-time synchronous fashion. It is a useful mechanism for distributing management data in a Local Area Network (LAN). Management data includes frequent updating of host Operating System (OS), security patches, OS update for network hardware, new configuration updates, etc. In the absence of any admission control or a source identification, any host with malicious intent can disseminate malicious codes or rootkits exploiting the underlying multicast framework. Routing protocols like RIPv2 and OSPF use a certain form of authentication to exchange routing information with their peer routers. However, their authentication and the distribution of routing information in its present form has several security and performance-related issues. Motivated through these problems, in this paper, we propose an efficient and scalable multicast architecture for distributing management and routing information in a LAN. We use Core-based Tree (CBT) for constructing the multicast delivery tree and the pseudo identity-based encryption of the underlying cryptosystem. We also demonstrate that our proposed multicast architecture is immune to a number of popular attacks.