Congestion Control And Load Balancing Routing Algorithm For Multi-layered Satellite Networks

Satellite networks have gained worldwide attention in recent years,particularly as an important part of the spatial information networks.Satellite networks have enormous potential to provide ubiquitous communication all over the world and meet the needs of military,business and individuals.Multi-layered satellite networks(MLSNs)consisting of hierarchically layered networks are aiming at construct efficient communication networks.MLSNs can carry out data transmission between satellites on different orbital planes as well as ground terminals,these nodes are connected via inter-satellite links(ISLs).The topology of satellite networks changes rapidly deriving from the mobility of satellites,therefore the design of efficient communication scheme and quality-of-service(QoS)stability of satellite networks is needed.In this paper,an optimized layered routing algorithm for GEO/LEO hybrid satellite networks is proposed.The proposed algorithm is developed based on congestion control technique,it delivers data traffic of the network according to the types of data flows.The algorithm also presents a multi-layered satellite network management method.The network management method is aimed at setting up reasonable network scheme based on the division of work.By the means of grouping satellites,information of the system is maintained by some specific nodes rather than every node,so that the scheme allocates the network resources reasonably.Simulations are conducted to show that the proposed algorithm can effectively reduce the average end-to-end delay as well as packet loss ratio of the satellite networks.This algorithm shows a strong potential to solve exiting problems in satellite communication networks and improves the performance of GEO/LEO hybrid satellite networks.This paper then proposes a network coding-based multi-path(NCMP)routing algorithm in two-layered satellite networks.NCMP combines the ideas of network coding with multi-path routing.With the advent of network coding,nodes are allowed to not only forward but also process the incoming traffic flows.Multi-path routing is intended to discover multiple routes from a source to a destination,it exploits multiuser diversity and increases wireless throughput.A time to live(TTL)value is employed by NCMP in order to restrain the time of routing setup and routing update processes.The process of checking independence of encoded packets is accomplished by operating on coding vectors rather than individual data bytes to avoid additional network overhead.Further techniques such as ACK procedure and selection of Galois Field are used to ensure efficient coding during data transmission.From the simulation results,we confirm that the proposed NCMP scheme outperforms the centralized routing algorithm in throughput,average end-to-end delay as well as packet loss ratio in satellite communication system.It is deduced that NCMP routing algorithm improves the MEO/LEO satellite networks routing performance.