Subject: [CCAMP] A review of draft-ietf-ccamp-flexigrid-yang

From: "Adrian Farrel" <[email-masked]>
Date: Thu, 24 Dec 2020 09:24:32 -0000

Hi,

As this draft is getting close to WG last call, I thought I would give
it a review. I worked on the flexi-grid control plane RFCs so I have
some interest in how this draft develops. I think it is looking in 
good shape although there may need to be some tweaks to align
with the other models that describe tunnels.

Here are some suggested edits.

Regards,
Adrian
---
1.
OLD
  [RFC7698] provides a framework GMPLS-Based control
NEW
  [RFC7698] provides a framework for GMPLS-Based control
END

---

1.
OLD
   This document identifies the flexi-grid components, parameters and
   their values, characterizes the features and the performances of the
   flexi-grid elements.
NEW
   This document identifies the flexi-grid components, parameters and
   their values, and it characterizes the features and the performance
   of the flexi-grid elements.
END

OLD
   An
   application example is provided towards the end of the document to
   better understand their utility.
NEW
   An
   application example is provided towards the end of the document to
   better understand the utility of this YANG model.
END

---

I think that sections 3 and 3.1 look a bit odd how they are. How about
moving them to 2.1 and 2.2 respectively.

It would also be good to add a diagram showing the relationship between
the various YANG modules.

---

I think Figure 2 could be cleaned up a little to show that the 
transponders are in optical edge nodes. Possibly...

                             Media channel
               <=======================================>
                                 Path x
               <--------------------------------------->

   +-----------+                                        +-----------+
   |  Optical  |                                        |  Optical  |
   |   Edge    |                                        |   Edge    |
   |           |                                        |           |
   |   ........|        +------+        +------+        |........   |
   |   :       | Link 1 |Flexi-| Link 2 |Flexi-| Link 3 |       :   |
   |   : Flexi-|<------>|  grid|<------>|  grid|<------>|Flexi- :   |
   |   :   grid|        |node B|        |node C|        |  grid :   |
   |   : Trans-|        +------+        +------+        |Trans- :   |
   |   : ponder|                                        |ponder :   |
   |   :    A  |              +----------+              |   E   :   |
   |   :       |     Link 4   |Flexi-grid|   Link 5     |       :   |
   |   :       |<------------>|   node   |<------------>|       :   |
   |   :.......|              |    D     |              |.......:   |
   |           |              +----------+              |           |
   +-----------+                                        +-----------+

               <--------------------------------------->
                                 Path y

---

Section 4

Could you please expand "TED" on first use.

s/provided on each situation/provided in each situation/

---

Section 4
      We refer to
      [I-D.ietf-ccamp-flexigrid-media-channel-yang] to complete this
      example.
Maybe...
      Details of how to configure a flexi-grid media channel can be
      found in [I-D.ietf-ccamp-flexigrid-media-channel-yang].

---

OLD
5.  YANG Model (Tree Structure) for Flexi-grid topology
NEW
5.  YANG Model (Tree Structure) for Flexi-Grid Topology
END

---

I think three of your informative references should be moved to 
normative:

- [I-D.ietf-ccamp-flexigrid-media-channel-yang]
- [I-D.ietf-ccamp-layer0-types]
- [I-D.ietf-ccamp-optical-impairment-topology-yang]