8.2 Early Results: ``Tweaked'' Congestion Avoidance Mechanism

The following day, after a great deal of tweaking all of the congestion avoidance algorithms, I ran the following test. Again, it transmitted a fully-reliable 1MB stream of 10,240 byte parcels.

 

Measurement Result

Total Data Acknowledged 1068.766 KBytes

Total Transmission Time 5.175 seconds

Network Bandwidth Utilization 206.525 KBytes/second

Average Round Trip Time 16.9 milliseconds

Average Window Size 10.7 packets

 

Table 8.2 shows the improvement here. This session sustained an average network bandwidth utilization of 206KBytes/second. Figure 8.4 even indicates, based on the slope of the curve, that the bandwidth utilization at peak hit 750KBytes/second!

  
Figure 8.4: Bytes Acknowledged ('C' test 2/27/97)

Figures 8.5 and 8.6 indicate that round trip times were a bit high and varied greatly, and that the window opened too quickly.

  
Figure 8.5: Round Trip Times ('C' test 2/27/97)

  
Figure 8.6: Packets In Network ('C' test 2/27/97)