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Spirent TestCenter: how do I configure a Simple back to back Priority Flow Control PFC Pause test?

Answer

This article explains the method to pause traffic in newer model cards, to use Priority Flow Control (PFC) according to the 802.1qbb standard. This article also  includes an example that shows how to configure and verify behavior.

Ensure that flow control is turned on (the default is off). 
 
Back to Back configurations  - PFC with Pause filter as described:
 
port 1 – Port 10 gig Advanced Priority 3
 
Create Raw Streamblock (1) Eth with Vlan priority 3  
Create a second Raw Streamblock (1B)  Eth with Vlan priority 5
 
port 2 –
 
Create Raw Stream (2) - Frame - Create New – Advanced – Eth 802.1Q – Priority Flow Control ls octet priority 3 – 00001000 time (3) 4096
 
Clear All results
 
Activate only the Vlan (1) priority 3 Streamblock, and Start traffic on port 1 and view rx Port Traffic -> Basic Traffic Results on port 2.
Start traffic on port 2, and no rx Port Traffic -> Basic Traffic Results traffic on port 2.
 
This proves that Vlan priority 3 Streamblock (1) traffic is blocked
 
Stop all traffic
Clear All results
 
Activate both Stream blocks (1) and (1B) and Start traffic on port 1 and and view rx Port Traffic -> Basic Traffic Results on port 2.
Start traffic on port 2 and view rx Port Traffic -> Basic Traffic Results traffic on port 2, and only Streamblock (1B) priority 101  is received -> Streams Filtered Stream Results traffic on port 2.
 
This proves that only Vlan priority 3 Streamblock (1) traffic is blocked and Vlan priority 5 Streamblock (1B) passes.
 
Note: the MSA 10G module only has one transmit queue, so if it receives a PFC pause request for a particular priority VLAN, it will stop ALL traffic. In the new version, the PFC traffic is only paused for the priority it is intended for.
 
If you want to pause untagged frames, select a Port 10 gig Advanced Priority 0.
 
Please reference attached configuration created in V4.33.

 

Product : Spirent TestCenter,PGA