Subject: Re: [Seamoby] Comments on the requirements draft

From: "Govind Krishnamurthi" <[email-masked]>
Date: Mon, 25 Mar 2002 12:32:10 -0500

James,

>It doesn't get info over a down interface, it gets it over the up
>interface. The protocol tells the MN what's available, including if the
>MN brought up the down interface. It avoids having to bring up the
>interface if there is nothing there.

[Govind] Agreed.
>
>If the interface is always up, then the MN can just do standard IPv6
>Neighbor Discovery and there is no need for CAR discovery.
>
> > >
> > >If the latter were not so, the MN could just use standard Router
> > >Discovery on the interface and there would be no need for CAR
>discovery.

[Govind] Again, this is possible, essentially what you are saying here
is explained in Example 2. But the fact is that if there are many such
APs then the process in Example 2 is expensive both in time as well
as bandwidth efficiency as well as power as pointed in my earlier mail.
[snip]

>CAR discovery is completely irrelevent if the MN brings up the
>interface. Neighbor Discovery is fine for discovering routers - the MN
>solicits router adverts, the routers send them. What's the problem?
>
>The only reason for CAR discovery is so that the MN doesn't need to
>bring up the interface to discover what's available. The sooner we can
>agree on that, the sooner we can get to the hard questions, like how to
>do it.

[Govind] I disagree. Again please see my previous answers.
I agree completely that we need
to get to the actual protocol designing process soon. But I don't
agree with your premise in the previous paragraph at all.

Regards,
Govind.

_________________________________________________________________
Send and receive Hotmail on your mobile device: http://mobile.msn.com

_______________________________________________
Seamoby mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/seamoby

---

From: "James Kempf" <[email-masked]>
Date: Mon, 25 Mar 2002 13:58:50 -0800

> as bandwidth efficiency as well as power as pointed in my earlier
mail.

I don't understand this. If the MN's power is up for it getting a
beacon, it presumably brought the interface up that far because it wants
to use it. What's the bandwidth and power consideration?

The harder case is how the MN finds out that it should bring up the
interface in the first place.

> agree with your premise in the previous paragraph at all.

Please explain.

You seem to think the problem lies in finding an AR when the MN has
already brought up an interface. I'm saying that that problem is already
solved by IPv6 router discovery.

I think the problem lies in the MN finding out that there is another
wireless technology available, so that it can bring up the interface far
enough to get the beacon.

That and doing reverse address translation for router/access point L2
identifiers to IP addresses.

            jak

---

From: "James Kempf" <[email-masked]>
Date: Mon, 25 Mar 2002 13:58:50 -0800

Please explain.

            jak