Key management plays a vital role in any communication network. Several schemes have been proposed to make key management efficient and usable. In this paper, the authors propose a secure and efficient key management scheme in multicast networks, SEGKMS, for achieving a secure communication between the communicating members in a cluster-based network. It makes use of a static group key for the group as well as ensuring forward and backward secrecies. It aims at obtaining better results with respect to the key management for multiple member leaves and joins. It guarantees a secure distribution of keys in the network along with a variable length public-private keys and the signatures used in the communication.