The goal of this work is to simulate the Random Random Detection algorithm (RED) and Double Slope Random Early Detection (DSRED) and Gentle Random Early Detection (GRED) modifications in Modelica. RED and its modifications allow to control the network load by selectively discarding packets before the queue is full and Transmission Control Protocol (TCP) begins to reduce the transmission rate preventing resynchronization. This selective packet loss helps TCP find the right data rate faster and keep the queue size and latency at the appropriate level. The existence of a large number of modifications of the classical RED algorithm is associated with the problem of selecting the parameters of the algorithm (queue thresholds, maximum drop parameter, etc.) under which the system would function stably and efficiently. The Modelica language is used as the implementation language. Based on the results obtained during the simulation it is planned to conduct a comparative analysis of the three algorithms with similar initial parameters to reveal the advantages of one or another algorithm. Copyright © 2019 for the individual papers by the papers’ authors.