Hi,

Comment inline below.

Yours Irrespectively,

John



Juniper Business Use Only
From: Lsr <lsr-boun...@ietf.org> On Behalf Of Robert Raszuk
Sent: Monday, January 10, 2022 7:15 PM
To: Les Ginsberg (ginsberg) <ginsb...@cisco.com>
Cc: Christian Hopps <cho...@chopps.org>; Aijun Wang 
<wangai...@tsinghua.org.cn>; Shraddha Hegde <shrad...@juniper.net>; Tony Li 
<tony...@tony.li>; Hannes Gredler <han...@gredler.at>; lsr <lsr@ietf.org>; 
Peter Psenak (ppsenak) <ppse...@cisco.com>
Subject: Re: [Lsr] BGP vs PUA/PULSE

[External Email. Be cautious of content]

Hi Les,

> You seem focused on the notification delivery mechanism only.

Not really. For me, an advertised summary is like a prefix when you are dialing 
a country code. Call signaling knows to go north if you are calling a crab shop 
in Alaska.

Now such direction does not indicate if the shop is open or has crabs.

That info you need to get over the top as a service. So I am much more in favor 
to make the service to tell you directly or indirectly that it is available.

[JD]  Right.  Just because a node is up and connected to the network does not 
imply that a given application is active on it.

Best,
R.





On Tue, Jan 11, 2022 at 1:07 AM Les Ginsberg (ginsberg) 
<ginsb...@cisco.com<mailto:ginsb...@cisco.com>> wrote:
Robert -

From: Robert Raszuk <rob...@raszuk.net<mailto:rob...@raszuk.net>>
Sent: Monday, January 10, 2022 2:56 PM
To: Les Ginsberg (ginsberg) <ginsb...@cisco.com<mailto:ginsb...@cisco.com>>
Cc: Tony Li <tony...@tony.li<mailto:tony...@tony.li>>; Christian Hopps 
<cho...@chopps.org<mailto:cho...@chopps.org>>; Peter Psenak (ppsenak) 
<ppse...@cisco.com<mailto:ppse...@cisco.com>>; Shraddha Hegde 
<shrad...@juniper.net<mailto:shrad...@juniper.net>>; Aijun Wang 
<wangai...@tsinghua.org.cn<mailto:wangai...@tsinghua.org.cn>>; Hannes Gredler 
<han...@gredler.at<mailto:han...@gredler.at>>; lsr 
<lsr@ietf.org<mailto:lsr@ietf.org>>
Subject: Re: [Lsr] BGP vs PUA/PULSE

Les,

We have received requests from real customers who both need to summarize AND 
would like better response time to loss of reachability to individual nodes.

We all agree the request is legitimate.

[LES:] It does not seem to me that everyone does agree on that - but I 
appreciate that you agree.

But do they realize that to practically employ what you are proposing (new PDU 
flooding) requires 100% software upgrade to all IGP nodes in the entire network 
? Do they also realize that to effectively use it requires data plane change 
(sure software but data plane code is not as simple as PI) on all ingress PEs ?

[LES:] As far as forwarding, as Peter has indicated, we have a POC and it works 
fine. And there are many possible ways for implementations to go.
It may or may not require 100% software upgrade - but I agree a significant 
number of nodes have to be upgraded to at least support pulse flooding.


And with scale requirements you are describing it seems this would be 1000s of 
nodes (if not more). That's massive if compared to alternative approaches to 
achieve the same or even better results.

[LES:] Be happy to review other solutions if/when someone writes them up.
I think what is overlooked in the discussion of other solutions is that 
reachability info is provided by the IGP. If all the IGP advertises is a 
summary then how would individual loss of reachability become known at scale?
You seem focused on the notification delivery mechanism only.

   Les

Many thx,
Robert

_______________________________________________
Lsr mailing list
Lsr@ietf.org
https://www.ietf.org/mailman/listinfo/lsr

Reply via email to