Hi Pascal,
I went through your draft about the concept of a Backbone Router to help
large-scale networks deployments. I have a few comments about the draft, I
put them below:
In Figure 1 you drew one single gateway that connects the backbone router
to the plant network. You do not refer to it later in the document. Is it
something application specific, a requirement for the backbone router
approach or a consequence to it? For any case, I would mention it or remove
it from the figure.
In Section 6.1, you wrote that Bacbone Routers announce themselves using
RAs that are broadcasted. Maybe you could see whether the solution proposed
in draft-chakrabarti-6lowpan-ipv6-nd-04.txt section 6.2 can help avoid
sending many broadcast messages. As a resume, they suggest:
" .. the PAN co-ordinator aka IPv6 router sends periodic RA to the
co-ordinators in its PAN by sending unicast messages to each of them...
Each co-ordinator can act as proxy IPv6 router advertiser and they can
broadcast the RA on behalf of the IPv6-router in their own domain
periodically.."
In Section 6.4, you mention that the target link-layer address is that of
the destination if a shorcut is possible over the Lowpan. Do you plan to
specify the mechanism that will tell the nodes if they have to go through
the Backbone Router or not for a communication? Shortly, how do the nodes
know if a shorcut is possible and better than the backbone route? Is it out
of scope of this document?
There are various benefits of the Backbone router approach that may be
mentionned in the document. If you let backbone routers take care of the
routing for the nodes for instance, it may result in only unicast packets
within the different lowpans (towards and from the backbone router), which
will have as consequences
1) less interferences (less packets in the air due to routes that are known
from the backbone router to the destination node and due to the shorcut
that the backbone may offer compared to long multihop communications)
2) less broadcast packets
3) reduced memory requisite for routing tables on the nodes
4) longer battery life for the sensor nodes.
This could be made more visible in the document.
Best regards,
Anthony
--
Anthony Schoofs
Research Scientist, Flexnod project, CCS Group
Philips Research WY 7-038
High Tech Campus 37 , 5656 AE Eindhoven, The Netherlands
Tel: (+31) 40 27 49 654
Email: [EMAIL PROTECTED]
_______________________________________________
6lowpan mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/6lowpan
