This is very interesting and relevant question.
In the scenario given, the utility side of the meter is likely a mesh also,
and it needs to be isolated from the home side (we're using SUN and HAN to
describe these two - Smart Utility Network and Home Area Network - in the
context of 802.15.4 work). The general desire of the utility to maintain a
secure SUN is one reason, and the general desire of consumers to keep their
HAN private is another (and the general 'we don't want a ninth grader with a
laptop crashing the grid' concern may figure in, too ;-). From either
perspective the meter forms an "edge" from the point of view as
entrance/egress between two logically separate networks. As pointed out,
this is still a resource constrained device (although in some
implementations it is has a bit more to play with than a typical thermostat
or light dimmer).
On the SUN side mesh the meter is keeping track only of it's adjacent
neighbors; on the HAN there are likely fewer neighbors, in the home
situation. But consider the same situation in an industrial context, where
you have the same need for the in-prem network to be separated from the
utility side, but the in-prem mesh might be thousands of nodes. I would
expect again that the meter/gateway is keeping track only of adjacent
neighbors. This is what we see happening now.
Not sure if that helps in the discussion, so FWIW.
-Ben
----- Original Message -----
From: "Richard Kelsey" <[email protected]>
To: <[email protected]>
Cc: <[email protected]>
Sent: Saturday, April 11, 2009 10:48 AM
Subject: Re: [6lowpan] [Roll] 6lowpan-ND vs. ROLL
Date: Sat, 11 Apr 2009 15:21:17 +0300
From: Zach Shelby <[email protected]>
>>> Richard Kelsey a écrit :
>>>> From: Carsten Bormann <[email protected]> Date: Fri, 10 Apr 2009
>>>> 19:00:42 +0200
>>>>
>>>> (I don't tend to think about the case where there is no Edge
>>>> Router -- ...)
>>>>
>>>> I have a question on this, stemming from my lack of familiarity
>>>> with the details of IP routing.
>>>>
>>>> Suppose I have a 6LowPAN/ROLL network being used for energy
>>>> management in a home. The network includes the electric meter,
>>>> which has a backhaul connection back to the utility. The utility,
>>>> being very protective of its backhaul network, has a firewall in
>>>> the meter to keep out everything except the utility's own
>>>> traffic. Given the presence of the firewall, does it still make
>>>> sense to use the meter as an Edge Router?
[Is an Edge Router an IP router? ... Yes.]
Anyways, this stuff doesn't need to be completely "typical". I mean we
are not installing an F-Secure firewall on a Windows PC here. These are
application-specific embedded devices most of the time. You can use an
embedded Linux box with Linux firewall features to achieve a 6LoWPAN
Edge Router. Of course the 6lowpan wireless interface driver and ER
features need to be implemented.
In the network I was describing, the meter has no more
horsepower than the other devices on the network. It has a
small micro with around 4k of RAM. It certainly isn't
something as powerful as an embedded Linux box. Is it
unreasonable to expect it to act as an Edge Router? If not,
how should its connection between the LowPAN and the utility
backhaul be handled?
-Richard Kelsey
_______________________________________________
6lowpan mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/6lowpan
_______________________________________________
6lowpan mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/6lowpan
