TCP performance through the COMBINE Interworking Unit

This paper presents results from experiments performed with the COMBINE Interworking Unit, showing that good TCP performance is possible with the shaper size dimensioned to 2000 cells. The shaper itself had been dimensioned using a Poissonian packet arrival model, assuming that the notorious burstiness of data traffic was a problem for higher layer congestion control. These results verify the validity of this assumption. It is also shown that good TCP performance was obtained, even under high cell loss conditions. These results highlights the importance of considering flow control mechanisms when performing network dimensioning, since the traffic is actually a function of the network topology and configuration over which it is sent.