| In this work, we present models for packet and bit error distributions in a Rayleigh fading channel.; A comparative evaluation of TCP performance using the two models indicates that the IID representation of packet errors for slow fading tends to predict higher throughput than will be observed. For fast-fading channels, the same model underestimates the throughput since it does not capture the fast transitions out of the fade state at the bit level. In contrast, the DTMC capturing memory at the bit level predicts TCP performance degradation in slow fading channels by modeling the average fade duration accurately. This model also shows the increased throughput that can occur in fast fading channels, since it captures the bit level transitions out of the fade state accurately. Finally, the effect, of providing error correction at different levels on TCP throughput shows that for fast and slow a breaking point occurs beyond which coding is ineffective. (Abstract shortened by UMI.)... |
