Abstract:

In order to solve the problems of RED（Random Early Detection) algorithm,such as sensitivity to time delay and parameter configuration,a stable random early detection algorithm is designed for TRED(Time-delay RED).TRED introduces Smith predictor to restrict the influence of time delay on network performance.TRED takes instantaneous queue length as congestion indicator instead of average queue length for fast system response.TRED modifies the probability function of RED as a nonlinear function and adapts the system parameter to the time-varying dynamics.By simulation comparisons,the results demonstrate that TRED successfully compensates for the time delay and keeps stable queue length in delay networks with various congestion degrees.TRED exhibits strong adaptability and guarantees satisfactory network performance.

Key words: congestion, active queue management, random early detection, time delay, stability