Satellite network simulator - design and verifcation using AODV and AntHocNet

[摘要] ENGLISH ABSTRACT: As access to space increases, the viability of creating satellite networks and dedicatedservices for satellite clients also increases. However, satellites are expensive to launchand cannot be easily maintained once in orbit, making it beneficial to simulate networkperformance before launch. Furthermore there is an extensive wealth of research regardingrouting protocols available for terrestrial networks that have not been fully researched forsatellite networks thus creating a need for a satellite network simulator.Any network has various ways in which its properties can be interpreted, which meansany network metric must be unambiguously defined. Routing protocols can be classified in various ways, showing their inherent advantages, disadvantages, requirements andlimitations. Combining these properties with information on the components of routingprotocols, an analysis of routing protocols can be made and candidate routing protocolscan be chosen. For this research AODV was chosen to allow functional verification andAntHocNet was chosen to show that the simulator is flexible enough to simulate variousrouting protocol functionality.Satellite networks were manually analysed with attention given to the key differencesbetween terrestrial and satellite networks. Using this information in conjunction withprevious research findings and recommendations, a vast distributed network similar tothe Iridium network was chosen as a verification scenario for the simulator. A previouslyproposed network, called the OuterNet, was chosen to further research the transferabilityof AODV and AntHocNet to other satellite constellations.The expansion of SatSim from a basic point-to-point simulator to a network simulatorcapable of handling complex routing protocols was documented in detail, with clearinformation given as to which design choices were made and why. The key design driverswere user-friendliness, modularity and re-usability, and the code was structured to allowusers to easily adjust and expand the simulator as needed. Due to the limited replicatableresults, further testing for the MAC layer channel access for AODV and AntHocNetimplementations was performed.SatSim was successfully expanded to allow for satellite network simulations. Preliminaryfindings regarding the suitability of AODV compared to AntHocNet for two differentsatellite constellations are presented.

[发布机构] Stellenbosch University