The TCP-friendliness of aggregate CP traffic is established by using the equation-based congestion control method described in  and used by TFRC .
While equation-based rate control guarantees TCP-compatibility over long time intervals, Figure 11 illustrates informally the behavior of a single C-TCP connection with two TCP connections during a short congested interval (time 5.0 through 9.0). Here we're interested in verifying that the behavior of the C-TCP flow does indeed appear to be compatible with that of the TCP flows.
In general, we see that the C-TCP connection mixes reasonably well with the TCP connections, receiving approximately an equal share of the available bandwidth. In addition, we once again observe the smoothness of its rate adjustments compared to the far more volatile changes in TCP flows.