Subject: Re: Mrouted on Windows NT

From: Dimitri Sidelnikov <[email-masked]>
Date: Thu, 17 Oct 1996 18:52:41 +0400

> Date: Tue, 15 Oct 1996 11:40:24 -0700
> From: Dino Farinacci <[email-masked]>
> 
>     When interworking with DVMRP and sparse-mode PIM, you have to get DVMRP
>     source's packets to the PIM RP so PIM receivers can get the data. This
>     can be accomplished by putting the RP at the border router which runs
>     both DVMRP and PIM. If you put the RP at an internal router inside the
>     PIM cloud, a cisco border router will send PIM Register messages to
>     the RP so data packets can make it to PIM receivers. For PIM source's
>     packets to get to DVMRP receivers, you have to get the DVMRP/PIM border
>     router to drag down the packets. In ciscos, as long as there is a source
>     in the DVMRP cloud sending to that group, the border router will capture
>     state about the group and start sending Joins to the RP. That will cause
>     data to be dragged down to the border router, so it can forward the data 
>     into the DVMRP domain.

Am I right that the latter implies the existance of (*,*,RP) routing entries?
DVMRP is dense-mode protocol and AFAIK it can only prune unwanted groups, but it 
cannot say which particular groups are welcome.

> 
>     That's how it works today with cisco's implemenation of PIMv1. We have
>     learned a lot from this experience and will incorporate slightly different
>     techniques for DVMRP to PIM-SM interaction for PIMv2. We have a separate
>     Internet Draft that documents this.
> 

- Which version of Cisco IOS is planned to support AUTO-RP (either Cisco-like or 
PIMv2-like)?
- Which version of Cisco IOS is planned to support (*,*,RP) routing entries?
- Suppose I'm going to set-up a transit PIM-SM network. So I'm receiving DVMRP 
routes from upstream DVMRP BB-1, and another my PMBR should announce these 
routes to a downstream DVMRP BB-2. Is there any other way to exchange DVMRP 
routes between the two PMBRs except making a DVMRP tunnel between them?

Thanks.
---
D. Sidelnikov

---

From: Dino Farinacci <[email-masked]>
Date: Thu, 17 Oct 1996 09:22:13 -0700

>>Am I right that the latter implies the existance of (*,*,RP) routing entries?

    That's what it means if your running PIMv2 inside your domain. I was
    explaining what ciscos do _today_.

>> cannot say which particular groups are welcome.

    This is true.

>> - Which version of Cisco IOS is planned to support AUTO-RP (either Cisco-like or 

    11.1(6.2) and 11.2(1).

>> - Which version of Cisco IOS is planned to support (*,*,RP) routing entries?

    Most likely our next feature release.

>> routes between the two PMBRs except making a DVMRP tunnel between them?

    Yes, one way is to run DVMRP unicast routing within the the PIM cloud so
    the upstream border can import routes that traverse through the PIM
    cloud to other borders. This is at the expense of storing these routes
    in the internal PIM routers.

    Another way is to manually configure the exterior DVMRP routes in your
    borders. And yes, yet another way is to use tunnels at the expense
    of non efficient distribution trees and additional management costs.

    However, if those DVMRP routes are also congruent with your unicast
    topology (you'll want this to happen if you go to native multicast 
    routing), then you don't need to do any of the above. This is the
    approach we (cisco) like to encourage people to take.

Dino

---

From: Petri Helenius <[email-masked]>
Date: Thu, 17 Oct 1996 21:38:20 +0300 (EET DST)

> >> - Which version of Cisco IOS is planned to support AUTO-RP (either Cisco-like or 

11.1(6.1). The 11.1(6.2) was pulled before it never got out.
Pete