From: Scott Morris (swm@emanon.com)
Date: Sat Jul 01 2006 - 22:51:59 ART
PIM NBMA mode has two features.
One is to handle the queue processing (not lumping IP multicast with routing
protocols in terms of choking outbound broadcast queue on a serial link).
The other is to "pay more attention" to individual join/leave requests from
spokes. Normal mode of operation on a multipoint interface (take ethernet
as an example) is to assume that if one endpoint hears something (someone
joining or leaving) that everyone else does too. This isn't the case in
multipoint frame relay. So for sparse mode operations some extra attention
needed to be brought to the proper handling of joins, leaves and in/out
interface lists for multicast groups.
Can you live without it? In many instances yes, but you'll find it much
more helpful if you have enabled it!
The broadcast keyword on a frame map lets the router know whether the
endpoint can even do group-addressing (multicast/broadcast). So if you only
have one broadcast-enabled PVC on a multipoint interface you likely would
see little gain in using the command. It can't hurt though! And remember
that over-configuration (as long as you aren't violating some other rule) is
not counted against.
Check out:
http://www.cisco.com/en/US/tech/tk828/technologies_white_paper09186a00800d6b
61.shtml
HTH,
Scott Morris, CCIE4 (R&S/ISP-Dial/Security/Service Provider) #4713, JNCIE
#153, CISSP, et al.
CCSI/JNCI
IPExpert CCIE Program Manager
IPExpert Sr. Technical Instructor
smorris@ipexpert.com
http://www.ipexpert.com
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Mike
O
Sent: Saturday, July 01, 2006 9:41 PM
To: Bob Sinclair; ccielab@groupstudy.com
Subject: Re: ip pim nbma-mode when to and when not to use it???
Bob,
So if I have a situation where I'm running sparse-mode and I need to go
across a frame-relay cloud then I need to enable ip pim nbma-mode? I thought
if you had p-t-p interfaces or DLCI's mapped with the broadcast keyword you
didn't need it.
----- Original Message -----
From: "Bob Sinclair" <bobsinclair@frontiernet.net>
To: "Mike O" <mikeeo@email.msn.com>; <ccielab@groupstudy.com>
Sent: Saturday, July 01, 2006 9:25 PM
Subject: Re: ip pim nbma-mode when to and when not to use it???
> Mike,
>
> If using Sparse Mode, PIM NBMA-Mode can be used to solve Outgoing
> Interface List problems on multi-point interfaces. It allows the
> source to be on one spoke and a receiver on another. It also permits
> the BSR to be on a spoke.
>
> What exactly do you mean when you say that "the could is broadcast"?
> OSPF Network type? It will not make any difference, AFAIK.
>
> Were you able to get multicast traffic from the source to all clients
> without using NBMA mode?
>
>
> Bob Sinclair
> CCIE #10427, CCSI 30427
> www.netmasterclass.net
>
> ----- Original Message -----
> From: Mike O
> To: ccielab@groupstudy.com
> Sent: Saturday, July 01, 2006 7:50 PM
> Subject: ip pim nbma-mode when to and when not to use it???
>
>
> I just completed a vendor lab and thinking I had ace'd the multicast
> section. I missed the ip pim nbma-mode command on the frame-relay
> interfaces.
>
> Now the Frame cloud was broadcast. It's my understanding that if the
> cloud
> is broadcast then ip pim nbma-mode is not needed.
>
> The multicast setup up was PIM v2 BSR sparse-mode. Would that make a
> difference?
>
> -Mike
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Tue Aug 01 2006 - 07:13:46 ART