...
We have also conducted more tests investigating the effects of RT Delay on Measurement (an impairment which should only affect TCP, of course). This cross-section was conducted with a 1Gbps rate limit implemented in a Token bucket filter on the path to the iPerf 2 Server.
Tests with concurrent iPerf 2 and Netprobe test streams have revealed the expected outcomes:
- Parallel TCP stream measurements are very sensitive to the background traffic, with the measured capacity reduced by more that 4 times the Netprobe rate.
- UDP stream measurements indicate reduced rate equivalent to the CBR Netprobe stream.
- One-way Delay measurements possible with Netprobe confirm the delay introduced by the Token bucket filter (4ms max), and illustrate the delay variability present when 3 TCP streams compete for capacity.