COMNET III CACI

The OFF command is a global processing command. It represents the time period when
the source is in its silent state, i.e. not transmitting any cells. The time delay modeled
here is 2500 microseconds, as determined by the parameter value 2.5 milliseconds. After
elapsing this delay, the ON command of is executed. This command sends 20 messages /
cells with an inter-arrival time between each cell of .000025 seconds, or 250
microseconds. The total delay for the ON period is therefore 500 microseconds. Again,
the cells are designated for one of the sinks following the ATM transport protocol where
the cell size of 53 bytes is specified. With these values, each VBR source generates
traffic at a rate of 2.8Mbps.
This architecture is simulated under different traffic loads by using the COMNET III
parameter called ‘Traffic scale’, which can be found under the menu entry ‘Define /
Backbone Properties’. Three simulations are run for a total of 5 seconds with the traffic
loads of 1, 2 and 2.5, i.e. a total traffic load of 9.2Mbps, 18.4Mbps and 23Mbps per sink.
Note that these values have been selected for demonstration purposes only.
The following table summarizes the results between the different traffic loads.
Delta
NODES: OUTPUT BUFFER TOTALS
REPLICATION 1 FROM 0.0 TO 5.0 SECONDS
PACKETS
BUFFER USE (P=PKTS, B=BYTES)
NODE ACCEPTED BLOCKED AVERAGE STD DEV MAXIMUM P/B
______________________ ________ _______ __________ _________ _________ ___
SE11 119735 0 89 82 479 B
SE12 119736 0 90 83 531 B
SE14 119736 0 90 83 530 B
SE13 119735 0 89 82 530 B
SE21 119238 0 77 115 1007 B
SE22 120231 0 80 120 1011 B
SE24 119916 0 79 118 1064 B
SE23 119553 0 75 112 1166 B
SE31 119681 0 2 11 116 B
SE32 120655 0 2 11 116 B
SE34 119492 0 2 11 116 B
SE33 119105 0 2 11 116 B
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