Cross-layer design challenges for Quality of Service guarantees in satellite networks

Satellite Communications plays a significant role in supporting next generation IP-based heterogeneous communication network infrastructure for broadband fixed and mobile services. Emerging media streaming, mobile broadcasting, content delivery and distribution, and broadband Internet access require Quality of Service (QoS) guarantees. Traditionally, satellite network protocol design has been based on a layered approach in which each layer in the protocol stack is designed and operated independently with interfaces between the layers. However, exploitation of cross-layer protocol optimization and engineering lead to efficient performance and provisioning of end-to-end QoS. In this paper we propose cross-layer protocol design approaches for satellite communication network. We provide a brief overview of cross-layer protocol optimization research emphasizing the interactions among, PHY, data links, network, transport and application layer. The interactions between physical layer and bandwidth allocation considering fade countermeasures, and dynamic resource allocation and the effect on transport control protocol (TCP) throughput are illustrated through examples. We provide some simulation results for geostationary (GEO) satellite network TCP throughput for different modulations at the physical level. Our simulation results demonstrate that the interaction/adaptation of these different layers of TCP/IP protocol stack for a satellite network improve the higher-layer goodput.