Subject: Re: [pim] Questions on draft-wijnands-pim-source-discovery-bsr-03.pdf

From: IJsbrand Wijnands <[email-masked]>
Date: Tue, 24 Sep 2013 13:55:32 +0200

Hi Sowmya,

Thanks for the response.

> I was going through the daft. Looks great. Nice way to bypass the need for RP and the register mechanism. The mechanism proposed has similarities of BSR & PIM-DM State refresh. 
> 
> Section 6 highlights the fact that the proposed protocol might not work for bursty traffic where traffic is sent in a burst once every 3 min in which case the packets may all be lost by the time the SG mapping message makes it from FHR to LHR and LHR's join makes it up to the FHR. I was wondering if we can flood the S,G traffic instead of just the SG mapping when the source becomes active and do this for a

With bursty sources the (S,G) tree will get deleted, so there is nowhere to flood the (S,G) traffic to, right? Or am I missing your suggestion?

Thx,

Ice.

> few seconds (allowing for max join propagation delay) or till the LHR sends the SG join we can be assured that the initial packets make it to the receiver. If the SG traffic reaches the LHR and there is no receiver it can send a prune upstream in addition to maintaining the SG mapping information. Incase a receiver gets added later the LHR can send a join upstream. Every 60 seconds FHR keeps sending the SG mapping message using BSR like messages to keep the SG mapping alive on all pim routers in the domain. 
> 
> Let me know your thoughts.. 
> 
> Best Regards,
> Sowmya

---

From: "Sowmya Krishnaswamy (sowkrish)" <[email-masked]>
Date: Tue, 24 Sep 2013 12:25:52 +0000

Hi Ice, 

The (S,G) tree will get deleted hence the need to flood on all PIM enabled
interfaces like in dense mode for a few seconds when the source becomes
active if the FHR has no prior (S,G) state. We could stop flooding after a
few seconds or once (S,G) JP state is created on that interface whichever
happens first.

Best Regards,
Sowmya

On 9/24/13 4:55 AM, "IJsbrand Wijnands (iwijnand)" <[email-masked]> wrote:

>Hi Sowmya,
>
>Thanks for the response.
>
>> I was going through the daft. Looks great. Nice way to bypass the need
>>for RP and the register mechanism. The mechanism proposed has
>>similarities of BSR & PIM-DM State refresh.
>> 
>> Section 6 highlights the fact that the proposed protocol might not work
>>for bursty traffic where traffic is sent in a burst once every 3 min in
>>which case the packets may all be lost by the time the SG mapping
>>message makes it from FHR to LHR and LHR's join makes it up to the FHR.
>>I was wondering if we can flood the S,G traffic instead of just the SG
>>mapping when the source becomes active and do this for a
>
>With bursty sources the (S,G) tree will get deleted, so there is nowhere
>to flood the (S,G) traffic to, right? Or am I missing your suggestion?
>
>Thx,
>
>Ice.
>
>> few seconds (allowing for max join propagation delay) or till the LHR
>>sends the SG join we can be assured that the initial packets make it to
>>the receiver. If the SG traffic reaches the LHR and there is no receiver
>>it can send a prune upstream in addition to maintaining the SG mapping
>>information. Incase a receiver gets added later the LHR can send a join
>>upstream. Every 60 seconds FHR keeps sending the SG mapping message
>>using BSR like messages to keep the SG mapping alive on all pim routers
>>in the domain. 
>>

---

From: "Sowmya Krishnaswamy (sowkrish)" <[email-masked]>
Date: Sat, 21 Sep 2013 06:54:58 +0000

Hi Ice/Stig/Michael,

Section 6 highlights the fact that the proposed protocol might not work for bursty traffic where traffic is sent in a burst once every 3 min in which case the packets may all be lost by the time the SG mapping message makes it from FHR to LHR and LHR's join makes it up to the FHR. I was wondering if we can flood the S,G traffic instead of just the SG mapping when the source becomes active and do this for a few seconds (allowing for max join propagation delay) or till the LHR sends the SG join we can be assured that the initial packets make it to the receiver. If the SG traffic reaches the LHR and there is no receiver it can send a prune upstream in addition to maintaining the SG mapping information. Incase a receiver gets added later the LHR can send a join upstream. Every 60 seconds FHR keeps sending the SG mapping message using BSR like messages to keep the SG mapping alive on all pim routers in the domain.

Best Regards,
Sowmya