Subject: VPL and VCL relationships

From: Eric Bomarsi <[email-masked]>
Date: Mon, 03 Nov 1997 14:22:04 -0500

Could someone please explain the intended relationship
between vpl and vcl entries in an end-system supporting
only PVCs?

Is the VPL table necessary in this case? If so, must vpl 
x be created before any vcls in path x can be created? 
Or can the vpl entry be automatically created when the 
first vcl in the path is created.

Thanks,
Eric Bomarsi

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From: "Michael H. Grobelch" <[email-masked]>
Date: Mon, 03 Nov 1997 13:48:56 -0800

>Date: Mon, 03 Nov 1997 14:22:04 -0500
 >From: Eric Bomarsi <[email-masked]>
 >Organization: xedia.com
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 >Subject: VPL and VCL relationships
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 >Is the VPL table necessary in this case? 

IMO, 

there is no "inheritance" relationship which requires a VPL 
if a VCL exists. In fact, they are mutually exclusive. One says
you are terminating a VPL, the other a VCL. 

I would consider it an error to attempt to
create a VCL on an interface using ifIndex, VPI of
a configured VPL. And conversely, to create a VPL on an 
interface using ifIndex, VPI of a configured VCL. 

Note that (mainly for switches) special cases of a VP tunnel 
(and in the future a Virtual UNI, aggregating multiple VPs) can 
require VPs and VCs on the same interface, but I favor the use
a separate ifIndex for the "logical" tunnel interface.

Mike

 >If so, must vpl