Re: [irs-discuss] IRS Problem Statement Posted

Susan Hares <> Wed, 01 August 2012 18:05 UTC

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From: Susan Hares <>
To: Alia Atlas <>
Thread-Topic: [irs-discuss] IRS Problem Statement Posted
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Date: Wed, 1 Aug 2012 18:03:22 +0000
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Cc: Thomas Nadeau <>, Nitin Bahadur <>, James Kempf <>, "" <>
Subject: Re: [irs-discuss] IRS Problem Statement Posted
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+1 on abstraction + filters (abstract/detail) IRS fits at the routing control.  

The real question about translation is what the translation is doing.  Is it translating one thing to another at the same layer of abstraction (e.g., Spanish/English, Ascii/ebcdic) or is it doing abstraction/detail change. 

I define translation as the same layer of abstraction.  Some people suggest translation = abstract/detailing.  We first need a common way to talk about the difference. 


By the way --- I'm thrilled about the pace of the discussion. 

-----Original Message-----
From: Alia Atlas [] 
Sent: Monday, July 30, 2012 6:40 PM
To: Susan Hares
Cc: Nitin Bahadur; James Kempf; Thomas Nadeau;
Subject: Re: [irs-discuss] IRS Problem Statement Posted


I certainly agree that we want IRS to have the ability to express
information at different abstraction layers and filtered on request.

There may still be a gap between the "network OS abstractions" and IRS
sub-interfaces; I'd be surprised if there weren't.  IRS is to provide
the bottom-up control strings.

IMHO, it's reasonable to have an entity that manages the translation.
For instance, one doesn't need a PCE-equiv in every application - nor
in every router; that might be an entity in between.

The quantity of information is part of why explicit filtering and
hopefully abstraction layers should be built into the data-models.


On Mon, Jul 30, 2012 at 9:24 PM, Susan Hares <>; wrote:
> Nitin:
> Exposing some network intelligence can either be done in detail or in some amount of summarization.
> If you are doing detail, you have bandwidth issues. If you are doing summarization or opacity, you are talking about layers of information.
> Apps need to find out what they need to get. They do not need all the details - just the fact they can get from point A to Point B (or for multi-cast B/C/D). They need to where they can go to date other applications.  They need a match-maker for the application who determine where the applications shall flow.  Now, if they are smart - like people going out to eat - they pick several ways go to eat traffic.
> The network orchestration then serves to be the paths to the place to eat.  This can either be distributed or centralized.
> If we have an Interface to routing, it need to have a two-layer concept of exposing information.
> Sue Hares
> -----Original Message-----
> From: [] On Behalf Of Nitin Bahadur
> Sent: Monday, July 30, 2012 3:33 PM
> To: James Kempf; Thomas Nadeau;
> Subject: Re: [irs-discuss] IRS Problem Statement Posted
> Hi James,
> This is not about splitting control plane and forwarding plane. It is about exposing network intelligence in the network elements to an external controller.
> And it is about allowing an external controller to use that information for enabling network-aware apps. And it is about allowing apps to influence the
> network element's RIB (not the FIB directly).
> Streaming is essential to allow for operations at scale...and avoid a request/response gated mechanism.
> Hope that helps.
> Thanks
> Nitin
> On 7/30/12 3:11 PM, "James Kempf" <>; wrote:
> I don't understand why streaming is specified in this draft. And I don't understand why this draft isn't put in the Forces framework. Forces is a framework explicitedly designed for device to controller communication. Its major drawback it that it is a framework with a hole in the middle, in that there are no specified devices. This draft would fill that hole.
> I don't think it is necessary to have a problem statement for router state update. Forces has already established that splitting the control plane into a separate device is, in some cases, an attractive design option. So I think this should be submitted to the Forces working group, or, at least, recast in the Forces framework.
>                 jak
>> -----Original Message-----
>> From:
>> [] On Behalf Of Thomas Nadeau
>> Sent: Monday, July 30, 2012 11:18 AM
>> To:
>> Subject: [irs-discuss] IRS Problem Statement Posted
>> Please review and discuss.
>> Thanks,
>> Tom, Alia, Ward
>> _______________________________________________
>> irs-discuss mailing list
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