Two buffer model-based QoS estimation method for 3G wireless IP networks in bullet trains

The high-speed communication service in future mass transportation systems is a challenging target for the design of next generation protocols. Especially bullet trains are promising, but the details of the real environments are little known to us. In this paper, we address the estimation of quality of service (QoS) in real mobile environments, assuming a radio link is proprietor and using only commercially available network devices. Firstly, we make a definition of invariant communication qualities in bullet trains, which are not dependent on each measurement. Then we propose a two buffer model-based QoS estimation method for the link qualities of commercial 3G wireless IP networks, even though the radio link is a black box to users and the protocol is proprietary. Finally, using this estimation method, we measured the raw packet transmission characteristics of CDMA2000 1timesEV-DO in bullet trains.