Hi Pete

Please see my response inline.

[PM]

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Document:  draft-ietf-roll-p2p-measurement-09
Reviewer:    Pete McCann
Review Date:  2012-02-05
IETF LC End Date:
IESG Telechat date: 2012-02-07

Summary:  Ready with nits

Major issues: None

Minor issues:

Section 5:
   An Intermediate Point MUST discard the packet with no further
   processing if the received MO is not a Measurement Request (i.e., T =
   0).
It wasn't clear to me at first why the Intermediate Points are not supposed
to see the Measurement Replies.  I gather this is because the RPL control
message used to send the reply uses a global or unique-local address
instead of a link-local address.  It may be worthwhile calling this
out explicitly
in Section 2 when you describe the two new RPL Control Messages.

Really, the Replies do pass through Intermediate Points but they are not
processed because they are not addressed to the Intermediate Point.  Right?

[MG]
So there are two different questions really:

Q1: Why the Intermediate Points are not supposed to see the Measurement Replies?
Ans to Q1:
The Measurement Reply is _unicast_ to the Start Point. So, the routers on the 
Measurement Reply's path treat it just as another data packet. The RPL code 
running on these routers never sees the Measurement Reply. So, if the RPL code 
on a router does see a Measurement Reply and this router is not listed as the 
Start Point inside the message, the router MUST discard the received message.

Q2: Would the Measurement Reply pass through the Intermediate Points (at any 
layer)?
Ans to Q2:
Let's first be clear about what an Intermediate Point is. The Intermediate 
Points are the routers on the route being measured excluding the Start Point 
and the End Point. Now, Section 6.1 clearly identifies the situations where the 
Measurement Reply _may_ travel back to the Start Point using the reverse of the 
measured route. So, it is possible that the Measurement Reply travels along the 
reverse of the measured path and, in this case, the Measurement Reply does pass 
through all the Intermediate Points. However, the End Point may decide to send 
the Measurement Reply along a different route (different than the measured 
route). In that case, the Measurement Reply may not pass through the 
Intermediate Points.

Hopefully this clarifies things. If you still think that the text needs to 
change, please let me know.

[PM]
Nits/editorial comments:

Section 1:
   situations, where
SHOULD BE:
   situations where

Section 5.3:
   and the route accumulation in on
SHOULD BE:
  and the route accumulation is on

[MG]
Thanks. I will make these changes in the final document.

Thanks
Mukul
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