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Some key issues with Wavelength Switched Optical Networks...

Hi folks, I haven't seen too many comments on our draft "Framework for GMPLS and PCE Control of Wavelength Switched Optical Networks" ( http://www.ietf.org/internet-drafts/draft-bernstein-ccamp-wavelength-switched-01.txt). So I figured I'd point out some potentially controversial issues that the draft brings up.

(a) The draft brings up models for the following WDM network elements:
  1. WDM links
  2. Optical transmitters
  3. Wavelength Converters and OEO regenerators
  4. ROADMs, FOADMs, optical splitters and combiners.
    For items (3) and (4) we are taking the modeling lead rather than some other SDO.  And for ROADMs, in particular, we going beyond the classic ITU-T "fabric" model (M.3100) which has been the mainstay of any connection oriented switch (TDM, ATM, MPLS).

(b) The draft brings up three (not one, not two, but three) different computational models for RWA which can impact GMPLS and PCE protocols:
  1. A single PCE computing both the path and wavelength
  2. Two distinct PCEs, where one computes the path, and a different PCE computes the wavelength assignment
  3. A PCE computes the path and wavelength assignment is accomplished in a distributed fashion via signaling (e.g., using label set objects)
    Do we really need all three models?

(c) G.709 includes the Optical Multiplex Section and Optical Channels.  RFC4238 was aimed at GMPLS extensions for G.709  (Optical Transport Network) control.  Weren't we finished with all this optical stuff years ago?

I'd like to think the draft answers some of these questions.  I also think that network element models and the process models are important enough to warrant this separate framework document.  Your opinions are solicited.

Regards

Greg B.
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Dr Greg Bernstein, Grotto Networking (510) 573-2237