Re: [spring] draft-filsfils-spring-net-pgm-extension-srv6-usid-07

[Peter Psenak <[e-mail]>]

Hi Rajesh,

On 10/09/2020 03:38, Rajesh M wrote:
> Hi All,
> 
> *Section 4.1.21:*
> 
> **
> 
> In control plane uA SID is advertised with value 2001:db8:0:*0N00:FNAJ::*
> 
> **
> 
> *in FIB entry it is represent with value *2001:db8:0*:FNAJ::/64*
> 
> Note: From a formal viewpoint, a uA SID of node N is defined by the
> 
> local FIB entry B:uA/64 of N (i.e. this definition is independent from 
> any uN SID of node N).
> 
> a) why such discrepancy ? between control plane and forwarding plane.

It's explained in the section 4.1.2.1:

"In order to signal in ISIS a container SID with the same routable 
semantics as End.X"

In other words, we wanted to keep the consistency in a way the SID is 
advertised for different SID types (e.g. END.X and uA).

thanks,
Peter


> 
> b) for uA SID Forwarding happens based upon 2001:db8:0/48 ? not based 
> upon 2001:db8:0:*0N00 (uN SID) ?*
> 
> **uSID block: 2001:db8:0::/48**
> 
> **for uA SID if forwarding is based upon**2001:db8:0/48 then 
> Compressed-SID can be 16 bit
> 
>     for uA SID if forwarding is based upon**2001:db8:0:*0N00 then 
> *Compressed-SID must be 32 bit**
> 
> **
> 
> Thanks
> 
> Rajesh
> 
> **
> 
> 
> Juniper Business Use Only
>