We consider scheduling real-time tasks in the presence of message loss and Byzantine node failures in unreliable networks. We present scheduling algorithms called RTQG and RTQG-B. The algorithms use quorum-based gossip communication strategies for dynamically and dependably discovering eligible nodes. Compared with its predecessors, our protocol exhibits better performance. RTQG utilizes quorum systems to limit the range of each gossip round. Using the intersection property of quorum systems, RTQG has advantages in message propagation and robustness to Byzantine node failures. Our simulation studies verify our analytical results.