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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 is connected via frame-relay to R2 Method1: Frame-relay de-list command R1 Configuration R1(config)#access-list 1 permit !-- packets sourced from with size > 500 will have DE bit set R1(config)#frame-relay de-list 1 protocol ip list 1 R1(config)#frame-relay de-list 1 protocol ip gt 500 !-- assign the DE list to …

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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 to 56K by default. This means that if you need to apply traffic shaping to only one PVC all other PVCs will be shaped to 56K by default. MQC shaping can be used to solve this problem by configuring shaping on specific PVC without the need to use the command …

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How-to: Configure Frame-relay Switching

Routers can be configured as Frame Relay switches to be used mostly in service provider or LAB environments. Lets see how you can configure frame-relay switch to use your in studies. On a Frame Relay switch, frames from a Frame Relay PVC arriving o­n an incoming interface are switched to a Frame Relay PVC o­n an outgoing interface. The switching paths taken by the frames are based o­n the static Frame Relay route table. In the following example two routers (Router1 & Router2) are connected via a router acting as a dedicated frame-relay switch (FRSW) . Configuration steps: Enable frame …

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How to Configure Frame-relay interfaces

Frame relay interfaces can be configured as Physical, Multipoint and point-to-point interfaces. Frame relay routing protocols and mostly all network configuration is heavily affected by interface type selected. In the following digram R1 is connected to R2 using frame-relay and we are going to explore different configuration options. Task1: Configure frame-relay PVC between R1 and R2 using physical Physical interfaces are considered to be multipoint interfaces by default, which means that address resolution is essential in order for both ends to communicate. Address resolution can be accomplished manually using the frame-relay map command or dynamically using inverse ARP. Dynamic address …

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