[j-nsp] Longest Match for LDP (RFC5283)

[adamv0025 at netconsultings.com]

Aah yes of course in-path RRs with NHS would do :)

Cheers,

 

adam

 

netconsultings.com

::carrier-class solutions for the telecommunications industry::

 

From: Krzysztof Szarkowicz [mailto:kszarkowicz at gmail.com] 
Sent: Tuesday, July 31, 2018 4:46 PM
To: adamv0025 at netconsultings.com
Cc: James Bensley; Juniper List
Subject: Re: [j-nsp] Longest Match for LDP (RFC5283)

 

You can turn ABR to inline Route Reflector and change the next-hop to self when reflecting the routes to access PE. Thus, access PE will require loopbacks of ABRs only. 

Sent from handheld device. Sorry for typos.

 

On Tue, Jul 31, 2018, 16:29 <adamv0025 at netconsultings.com <mailto:adamv0025 at netconsultings.com> > wrote:

> Of Krzysztof Szarkowicz
> Sent: Monday, July 30, 2018 8:51 PM
> To: James Bensley
> Cc: Juniper List
> Subject: Re: [j-nsp] Longest Match for LDP (RFC5283)
> 
> 
> > On 2018-Jul-30, at 17:13, James Bensley <jwbensley at gmail.com <mailto:jwbensley at gmail.com> > wrote:
> >
> > On 30 July 2018 at 15:22, Krzysztof Szarkowicz <kszarkowicz at gmail.com <mailto:kszarkowicz at gmail.com> >
> wrote:
> >> James,
> >>
> >> As mentioned in my earlier mail, you can use it even with DU. If ABR
> >> has
> >> 10000 /32 LDP FECs, you can configure LDP export policy on ABR to
> >> send only subset (e. g. 20 /32 FECs) to access.
> >>
> >> Saying that, typical deployment is with DoD, since typically access
> >> PEs (and not ABRs) have better knowledge which loop backs are needed.
> >> So, basically access PEs send the info to ABR, which loop backs are
> >> needed, and which loop backs are not needed via LDP DoD machinery.
> >
> > Hi Kryzstof,
> >
> > This was exactly my point:
> 
> I have seen a deployment, where services were deployed via some
> centralized provisioning system. Part of the service provisioning was to adjust
> the LDP export policy on ABR, since LDP DU was used (some access PEs didn’t
> supported LDP DoD in that deployment). So, if you have some devices
> without LDP DoD support, your only choice is LDP DU + policies :-).
> 
Or BGP-LU + policies,

One follow up question, 
What about the case, where the minimum set of /32 loopback routes and associated labels is simply beyond the capabilities of an access node.
Is there a possibility for such access node to rely on default route + label -where originator of such a labelled default-route is the local ABR(s) in "opt-B" role doing full IP lookup and then repackaging packets towards the actual NH please?


adam

netconsultings.com <http://netconsultings.com> 
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