RE: [PWE3] PWE3 new WG items? PW QoS

["Busschbach, Peter B (Peter)" <busschbach at lucent.com>]

Peter>- Are segments set up in a random order or is there a need 
> for a certain sequence of message?
> >  
> >
Scott> For scaling and robustness you can't require a certain order of setup.
> 

Scott,

Assume one wants to set up a multi-segment from A via B and C to D to carry ATM traffic. Suppose that the segment between B and C is set up independently from the other two segments. Then it is possible that B indicates to C that it accepts a maximum number of ATM cells per frame equal to N1. Subsequently, B could learn from A that A accepts a maximum number of ATM cells per frame equal to N2. If N2 is smaller than N1, there is a problem. B might have to repackage frames it receives from C to make sure it doesn't exceed N2 cells in the frames it forwards to A.

Based on this example, it seems obvious to me that B has to receive a PW setup message from A before it can forward it to C and C has to receive a setup message from B before it can forward it to D. In other words, there is a clear order.

Peter 

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