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Frame-relay Discard Eligibility Bit (DE)

What is the DE bit ? The DE bit is used to indicate that the frame has a lower importance than other frames and should be dropped first if the network experienced congestion. How to set the DE bit? We can use a simple network to test our configuration. R1 …

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Frame-relay traffic shaping using MQC

To apply frame-relay traffic shaping using a normal map-class, the command frame-relay traffic-shaping must be applied to the main interface. This method has a pitfall; the problem is that when you apply the frame-relay traffic-shaping command to the main interface any DLCI that has no explicit map-class will be shaped …

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CAR – Rate limit examples

CAR is a policing mechanism used to limit the transmission rate of some traffic flow. Cisco actually recommends using MQC policing for its modularity and features, but CAR is still used widely in most operational networks for its simplicity. CAR can be used whenever you need to place a limit …

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PBR as a QOS tool

In order to apply QOS policies in your network, traffic should be classified first. There are many techniques available for packet classification. PBR is one of these techniques as discussed below. PBR can be used to match a specific flow and then apply QOS policies on it, like marking this …

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