This report presents the overview of traffic management functions and techniques in ATM networks, as well as TCP congestion control schemes and TCP adaption to ATM networks. In particular, we analyze the problem of ensuring TCP packet integrity in transmission over ATM networks. To solve this problem, the mechanism EPD (Early Packet Discard) was implemented and tested by a series of simulations. After the analysis of results and in order to cope with the difficult issue of positioning a fixed EPD threshold value in advance, we propose an extension to EPD which consists in adjusting dynamically the level of the threshold, depending on the occupancy of queues in ATM switches. The benefits of this solution are demonstrated by the simulations.