What do you set the limit to? What do you do when a router fails and your available bandwidth suddenly drops? All of the TCP end hosts will backoff properly and avoid melting the network with endless re-transmits. All of the TCP flows will converge towards sharing the available bandwidth, even if that is a moving target. Applying a congestion control algorithm on top of UDP like the other response says is fine. Perhaps TCP's specific congestion control scheme isn't what you need (it sucks at live video for example). But you really do need a congestion control algorithm.