Network Performance Optimization Algorithm In Large-scale Bus-based Network

There are a lot of study focuses on the special case of delay tolerant network—bus-based delay tolerant network. Many routing algorithms, such as epidemic routing,have been proposed in the previous literature. However, few works study routingalgorithm in the real bus scenario. In this thesis, we envestigate the packet forwardingprocess in the case of a real bus. A K-transmissions epidemic routing algorithm and ascheduling algorithm based on the maximum number of packets are presented, andthe simulation results show that they can improve the network performance.We first study the trace file collected from the bus running in the City of Chicago,and know there are a lot more than two buses meet at the same time, that is, in thecase of more than one bus communication within the scope of the buses at some timepoint. Therefore, we then propose a K-transmissions epidemic routing algorithm. Thisalgorithm can be balanced by adjusting the value of K to the number of copies of thepacket and the average transmission delay. Finally, the simulation compares the twocases of K-transmission epidemic routing algorithm when K=1and K=∞. We foundthat when K=1, the number of copies in the network is always less than the number ofcopies of K=∞. At the same time, the average transmission delay of K=1is biggerthan K=∞in some extent.Then, for the case of a bus having two or more than two bus within itscommunication range at the same time, we study the choice of a suitable bus tocommunicate in order to reduce the number of copies of the network packet. In thispaper, we propose the maximum number of packets scheduling algorithm (MNPS). Itsmain idea is to choose a neighbor with the maximal number of packets to be receivedreception to communicate. simulation. The experimental results in the bus collectedfrom the City of Chicago running trace show that, compared with the theK-transmission epidemic routing algorithm, the MNPS algorithm can greatly reducethe number of copies with a little increasing in delivery ratio.