Riverstone Networks WICT1-12 User Manual

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Riverstone Networks RS Switch Router User Guide   Release 8.0   30-23
WAN Configuration
WAN Rate Shaping  
Performing Rate Limiting
If the 
burst-queue-depth
 is set to zero for a particular template, WAN rate shaping for the affected flows effectively 
becomes rate limiting. This switch to rate limiting occurs because without a queue, packets are simply dropped 
whenever the bit rate of a flow reaches Bc and/or Be.
Non-Rate Shaped Flows
If Ethernet flows that are not controlled by a WAN rate shaping template are mixed with flows that are controlled. The 
non-rate shaped flows will disregard the rate shaped flows and take as much bandwidth as they can. For this reason, 
it’s generally not a good idea to mix rate shaped and non-rate shaped flows on a WAN port.
Rate Shaping in Both Directions
WAN rate shaping works best when it is applied in both directions. In other words, if you apply rate shaping to an RS 
WAN port going into the WAN, you also should apply rate shaping to the RS WAN port at the other end of the 
connection. Applying rate shaping to each RS allows connection-oriented protocols, such as TCP, to communicate 
more efficiently and experience fewer instances that could potentially trigger crank-back.