Comments on LMP draft 3

[Fugui Wang <fwang@axiowave.com>]

Hello Jonathan,

Here are some comments regarding draft-ietf-ccamp-lmp-03.txt:

1. In page 5, section 3:
"Rather, a node-wide unique 32-bit non-zero integer control channel
identifier
CCId) is assigned at each end of the control channel. This identifier comes
from the same space as the unnumbered interface Id."

If the control channel is directly on ethernet instead of point-to-point 
interface or IP tunnel, what should be chosen as the CCId?
For example, in the following case, if Node A, B, C are connected by 
ethernet. Node B should have a control channel to A and C respectively.
What should be the CCIds for these two control channels? In this case
interface ID is not able to uniquely identify the control channel.  

    .1                  .2                     .3    10.1.1.0/24
----+--------------------+----------------------+--------------
    |                    +                      |
+---+---+            +---+----+            +----+----+
|ifId=2 |            | ifId=3 |            |  ifId=4 |
|   A   |            |   B    |            |    C    |
|       |            |        |            |         |
+-------+            +--------+            +---------+

2. In page 9, section 3.2:
"The LMP Hello protocol is intended to be a lightweight 
 keep-alive mechanism that will react to control channel failures 
 rapidly so that IGP Hellos are not lost and the associated link-
 state adjacencies are not removed unnecessarily."

I don't quite understand how LMP hello could prevent IGP hello lost.
My understading is: as far as there is at least
one contral channel active between the neighbor, IGP won't remove the
link-state adjacency, even without LMP detecting the control channel
failure.
Is that right? 

3. In page 9, section 3.2.1:
"If the fast keep-alive mechanism of LMP is not used, the 
 HelloInterval and HelloDeadInterval parameters MUST be set to zero."

This paragraph says that the Hello could be optional. However, in the
Control channel FSM, it seems that this case is not considered.



Thanks,
Fugui