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Re: ECN posted 08/13/2004
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Could you include a link to where you found that?

Thanks
----- Original Message ----- 
From: <gladston@xxxxxxxxxx>
To: <ccielab@xxxxxxxxxxxxxx>
Sent: Friday, August 13, 2004 4:30 PM
Subject: ECN


> Any example of using ECN between 3 routes?
>
> I could not make a logical map of how it works reading Cisco Doc.
>
> If R1 sends a packet marked with ECT and CE, then would R2 learn that R1
is ECN capable and would consider this information when sending packets back
to R1?
>
> =====================================
> from Cisco
>
> If the number of packets in the queue is between the minimum threshold and
the maximum threshold, one of the following three scenarios can occur:
>
> If the ECN field on the packet indicates that the endpoints are
ECN-capable  and the WRED algorithm determines that the packet should have
been dropped based on the drop probabilitythe ECT and CE bits for the
packet are changed to 1, and the packet is transmitted. This happens because
ECN is enabled and the packet gets marked instead of dropped.
> =======================================
>
> If R2 receives a packet from R1 with ECN field saying that it is a ECN
capable, which device R2 considers ECN capable, the routers that sends this
packet or the device to which this packet will be send?
>
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