Group key distribution is faced with two important problems, i.e. reliability and scalability, to support security multicast for large and dynamic groups. With group member increasing, traditional reliable multicast protocol can not deal with them fully. In this paper, we provide gossip-based group key distribution idea for wide-area dissemination. It is a gossip-based loss recovery control mechanism, which can provide a probabilistic reliable guarantee for information dissemination. To achieve full reliability, we provide three layers protocol model in group key distribution. One is best effect layer, which provides unreliable dissemination. Other is gossip-based loss recovery layer, which provides probabilistic reliable guarantee. Last is sync-based layer, which provide deterministic loss recovery. We integrate probabilistic loss recovery method with deterministic one. To evaluate the effectiveness of gossip technique in scalable and reliable multicast protocols, we compare gossip protocol with other reliable multicast protocols. Experimental result shows that gossip protocol has better scalability than others.