Single Flow RBUDP & Multiple Flows TCP

Just as for the tests described in the "Single Flow UDT & Multiple Flows TCP", the intension of these tests is to study the TCP friendliness of the RBUDP protocol and to compare it with UDT. However, there should be noted that the developers do not claim that RBUDP is TCP friendly: their most important objective is to obtain a bandwidth as high as possible. As in the UDT & TCP section the TCP friendliness has been studied by measuring the effect of one large RBUDP flow upon many, small TCP flows that are again generated with a modified version of the Iperf traffic generator. Also in these tests the RBUDP flow will be started as first and after some time the TCP flows, or the other way around. The TCP flows are generated between two sets of N DAS-2 cluster nodes which are separated in two VLAN's. To obtain sufficient diversity in the # flows, each node in the source VLAN is sending one flow to each of the N receiving nodes in the destination VLAN. A flow between sender and receiver may consist of one or more parallel streams.

In these the following parameters have been varied:

• The TCP Node pairs N that are used in both VLAN;s.
• The RBUDP data size.
• The shaping TCP bandwidth taken as a sum over the threaded parallel flows. However, here only sum shaping TCP bandwidths of 50 Mbits/s and 100 Mbits/s for each source - destination pair have been used.
• The # threaded parallel flows.

In the next sub-sections some parameter cross-sections of the data sets described in the previous section will be presented.