RE: Comments on "draft-li-ccamp-wson-igp-eval-01.txt"

"Bardalai, Snigdho" <> Thu, 07 August 2008 04:13 UTC

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Subject: RE: Comments on "draft-li-ccamp-wson-igp-eval-01.txt"
Date: Wed, 6 Aug 2008 23:09:16 -0500
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In-Reply-To: <DEA39C2524E24C07A9B2818AAF42A2A6@dan>
Thread-Topic: Comments on "draft-li-ccamp-wson-igp-eval-01.txt"
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From: "Bardalai, Snigdho" <>
To: "Dan Li" <>, "Ccamp (E-mail)" <>
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Hi Dan,
Please see my response below.

-----Original Message-----
From: Dan Li []
Sent: Friday, August 01, 2008 4:10 AM
To: Bardalai, Snigdho; Ccamp (E-mail)
Subject: Re: Comments on "draft-li-ccamp-wson-igp-eval-01.txt"

Hi Snigdho,
Very good question! See my comments below.

----- Original Message ----- 
From: Bardalai, Snigdho <>  
To: Ccamp (E-mail) <>  
Sent: Friday, August 01, 2008 4:26 AM
Subject: Comments on "draft-li-ccamp-wson-igp-eval-01.txt"

Hi Adrian and Dan, 

I have the following comments on this draft. I was wondering what were the objectives for the IGP evaluation. IMHO the evaluation from WSON perspective should address the following:

1. IGP usage in the context of traditional distributed solutions for WSON 

[Dan] With the situation that TE information is already be carried by IGP, it's nature to think that the wavelength information can also be carried by IGP. I am not saying it should be, but it's worth to look at.
[Bardalai, Snigdho] Do you see any particular issues with using the IGP for this purpose ? 

2. IGP usage in the context of PCE solutions for WSON

[Dan] It's a potential way for PCE to get the wavelength information.
[Bardalai, Snigdho] Since the PCE is the location where path-computation takes place is it possible to limit LSA advertisements from PCC to PCE neighbors, instead of to every PCC neighbor?

3. Flooding and refresh of static and dynamic link state updates

[Dan] Try to figure out the impact to the performance of IGP.
[Bardalai, Snigdho] Is it possible to limit refreshing of static LSA? Ex. using the OSPF "do not age" concept?

4. Data base sync-up during node restarts

[Dan] Yes, this should be considered. Especially the very large amount of data will be sent to the restarting node. We may consider the point to point data exchange instead of flooding the LSA updates. Or slice the big data packet into small pieces.
[Bardalai, Snigdho] This is little tricky, I would be interested to see if there is a clean solution.

Could you please let me know if the above is within the current scope? I believe that these are important.