Abstract: A network congestion control system and method facilitate the transmission of information on a communication network by monitoring the data streams coming out of the communication network for congestion notifications, and actively rate controlling the end user application sessions based on such congestion notifications to alleviate the network congestion. This provides congestion control for the network and can be used to avoid congestion reaching the point where the network has to discard data. The end user sessions can be divided into mission critical sessions and non-mission critical sessions. These session types can be prioritized so that non-mission critical sessions are rate controlled during periods of congestion, while mission critical sessions remain unaffected. Mission critical sessions are effectively reserved a specific amount of bandwidth with the rest of the available bandwidth (up to the congestion point) being allocated dynamically to the non-mission critical sessions.