Cross-layer reliability management for multicast over satellite

Multicast services are well supported by geostationary satellites as a result of their broadcasting capability over large coverage areas. However, in this context the reliability management must be accurately analysed, since satellite resources are expensive and link quality degrades significantly during adverse weather conditions. In this paper, we show that the conventional layered approach of reliability management can be adapted and optimized for multicast over satellite. Our proposal consists in removing, at low layers, most of packet discardings, and introduces the MPHP mechanism which protects protocol headers. At transport level, for full reliability, we adapt conventional erasure decoding used with packet-level FEC and on this basis we propose a hybrid-ARQ protocol with a specific error and erasure decoding. The performance analysis shows that applications like real-time multimedia delivery using UDP-lite for partial reliability can benefit from a reduced error rate, and applications like massive file transfers requiring full reliability are less demanding in terms of network resources.