Subject: [netext] Comments on draft-bernardos-netext-pmipv6-flowmob-03

From: Behcet Sarikaya <[email-masked]>
Date: Mon, 27 Jun 2011 11:25:28 -0700 (PDT)

Hi Carlos,
  I read the draft, here are some comments:

Abstract.
The abstract is badly written. It contains nothing about the content of the 
draft. The text up to The ability of movement
   of selected flows from one access technology to another

should be deleted. Some new sentences should be added that really describe the 
content of the draft. Maybe some sentences from Section 1 can be borrowed.

About the overall structure.

Why don't we have a section on LMA behaviour and another on MAG behaviour? 
Section 6 has MN behaviour. I realize the draft comes up with a lot of 
changes/extensions to what LMA/MAG does.

Section 3.

Too much out of scope text. This seems to be due to ML discussions and policy 
stuff. 

I found it disturbing to the reader the extent of out of scope issues.

Use Case 2. common prefix. Again, I think that this case is overblown. What 
happened to HI in 5213? Case 2 is against HI=1, how can you avoid a MAG to 
assign 1 to HI? The whole multihoming extension is at stake here. 

Basic operation. It says:
   the LMA does not need to perform any kind of signaling in order to
   move flows across the different physical interfaces.

 Why have this in a draft on flow 
mobility?
Isn't it better to ignore such cases than having it and not only having it, 
covering it to such an extent?

Besides, let's look in Figure 2. LMA decision to move flow Y.
Why not let the MAG2 know it? This way we have one consistent signaling and also 

we can make sure MAG has the right flow state.

Fig. 4 and related text. 
Why moving Flow Y is considered also moving the pref2? What happens if MN had 
another flow on Pref2?

Why do we have BRI/BRA exchange  in a flow mobility draft? Why not replace them 
with FMI/FMA?

End of Fig. 5.
It says:
Note that this specification also supports flow mobility at a finer
   granularity (not just on a prefix level).  This is done by including ...

I like the first sentence but I would like to see how this is delivered. 
Currently there is no justification for it.

Sec. 5.1 
Who registers BIDs? 

It is good to admit in this draft that we are deviating from the multihoming 
design in 5213. I 

had suggested including such changes in a different draft.
 I think it still 
stands. 

Regards,

Behcet