Subject: Some comments on draft-dimitri-ccamp-gmpls-ason-routing-ospf-00.txt

From: "Dean Cheng \(dcheng\)" <[email-masked]>
Date: Tue, 18 Jul 2006 11:07:09 -0700

Dimitri,
 
I've some comments now as follows:
 
1) The third paragraph of section 6.1, it says, "....However, an
    additional restriction MUST be applied such that the RC 
    selection process takes into account that an upper level may
    be adjacent to one or more lower levels."
 
    It would be good to clarify the words "one or more lower levels"
    here. From the sentence after that, it actually means one or 
    more areas at the lower levels.
 
2) In section 6.1, it says that the D bit is used together with the
   "Associated Area ID" sub-tlv, as "an additional restriction". In
    the same section, it does not mention the use of that sub-tlv
    along with U bit.
 
   But in section 6.2.1 and 6.2.2, it explicitly says that the
"Associated
   Area ID" sub-tlv is included when re-originating the opaque LSA 
   downward or upward. 
 
   It would require clarification and consistency here.
 
3) In section 6.1 (Discovery and Selection), it describes a method
    for "selecting" the RC that performs the upward/downward
dissemination
    of routing information. 
 
    What happens if RC1 is currently the RC that doing the upward
advertising
    but RC2 just becomes active with U-bit set and a higher Router ID ? 
 
    I guess the same handling as OSPF DR's election can be used for
    stability purpose, and also for consistency, and if so, needs to be
stated 
    in this section. And for that matter, the word "selection" vs.
"election"
    does not really make much difference.
 
4) In section 7.2, it is also useful to add that the number of levels be
under
    policy control.
 
5) It would be useful to add an interoperability section, which
describes how
    an traditional OSPF node/network interoperates (if need to) with an
OSPF 
    node/network with extensions as described in this ID. E.g., a
reachable
    address (prefix) is advertised by an ABR normally but with this ID,
can also
    be advertised through hierarchy.
 
Thanks
Dean

---

From: dimitri papadimitriou <[email-masked]>
Date: Tue, 18 Jul 2006 22:34:42 +0200

dean

thanks for commenting - see in-line

>     more areas at the lower levels.

ok

>    It would require clarification and consistency here.

i will split this section 6.1 into two parts and refer to section 6.2 
for the case addressed by that section

>     in this section. 

indeed hysteresis mechanism is needed in such condition

> And for that matter, the word "selection" vs.
> "election" does not really make much difference.
>  

ok

>     be advertised through hierarchy.

i guess you mean a GMPLS LSR not implementing these extensions ?

thanks,
- dimitri.