Customer Service Center
Home
Knowledge Base
Contact Support
License Activation
|
Contact Support
|
License Activation
|
Spirent KB Article
Doc ID: FAQ17133
Printer Friendly
Email Article Link
Spirent TestCenter: Why does flow count change drastically when modifier is used?
Environment/Versions
VFD
Frame Editor
Device count 1000
VLAN increment by 1
Stream block
Modifier on UDP port number count (quantity)
Answer
UDP port number count modifier set to 37 gives 37000 flows but when set to 32 gives only 4000 flows.
Here is an explanation of why you are seeing the modifier behavior.
You have 1000 device count.
When you set the modifier on the UDP port, it will try to set the same quantity for each value.
Let’s use a device count of 6 for explanation purposes.
Example: UDP modifier set with a count of 3.
Device 1 – UDP port 1024
Device 2 – UDP port 1025
Device 3 – UDP port 1026
Device 4 – UDP port 1024
Device 5 – UDP port 1025
Device 6 – UDP port 1026
As you can see a UDP count of 3 will give an equal number of UDP port values (2 for 1024 and 2 for 1025 and 2 for 1026).
So only 6 flows with a UDP count of 3.
Next Example: UDP modifier set with a count of 4
Device 1 – UDP port 1024
Device 2 – UDP port 1025
Device 3 – UDP port 1026
Device 4 – UDP port 1027
Device 5 – UDP port 1024
Device 6 – UDP port 1025
We don’t see equal number of UDP port values (2 for 1024, 2 for 1025, 1 for 1026, 1 for 1027) so we have to add another 6 devices.
Device 1 – UDP port 1026
Device 2 – UDP port 1027
Device 3 – UDP port 1024
Device 4 – UDP port 1025
Device 5 – UDP port 1026
Device 6 – UDP port 1027
After adding 6 more devices (total 12) we now see equal number of UDP port values. All have 3 each. (3 for 1024, 3 for 1025, 3 for 1026, 3 for 1027)
So this will result in 12 flows.
If this is not the desired configuration, possibly changing the modifier such as using the repeat field may produce a more desirable set of flows.
Using the repeat count will allow a configuration that can give each device the same number of UDP port values.
Version
1.0
Publish Date
2015-12-10
Categories
Product : Spirent TestCenter,PGA
Related Articles