QoS Routing for LEO Satellite Networks

Since the population distribution on the earth surface is highly non-uniform, the traffic requirements are unbalanced in LEO (Low Earth Orbit) satellite networks, some ISLs(Inter-Satellite Link) of satellite networks are congested while others are underutilized.This work proposes a QoS routing protocol for LEO satellite networks called BQR (Balanced QoS Routing) on the Iridium Constellation that implements a balanced mechanism based on the population density. The occupancy factor has a classification by location of the satellite and changes according the countries where the satellite is flying above. The countries with high population will receive high value of occupancy factor that will help to calculate the ISL cost based on a combination of propagation and queuing delay. The routing table maintains many entrieswith different ISL cost for the same destination, a path with high ISL cost has less probability to be selected that will balance the satellite network traffic.The integration between OPNET and STK is used to simulate the proposed BQR routing protocol. The simulation results show that our protocol can achieve a better traffic load balancing that leads to minimize the end to end delay and optimize the throughput.