Re: [DNA-BOF] Detecting Network Attachment BoF description (rev 2)

[Gregory Daley <Greg.Daley@eng.monash.edu.au>]

Hi Alper,

----- Original Message -----
From: Alper Yegin <alper@docomolabs-usa.com>
Date: Thursday, June 19, 2003 10:53 am
Subject: Re: [DNA-BOF] Detecting Network Attachment  BoF description 
(rev	2)

> 
> > I see mobility/movement as basically disconnection from one
> > subnet and connection to another.
> 
> I think we need to differentiate between link/subnet/prefix changes.
>  
> For example, host might change its access point (L2 bridge) but it 
> may stay
> connected to the same access router. In this case, there is no change
> required in the IP state.


How about we call this "Link-layer only" handover?
Is there a better term?

> Or, host might change its access point and consequently access 
> router, but
> the two routers might be advertising the same prefix. In that 
> case, IP
> address of the host does not change, but default router 
> information must
> change. So, even if the subnet does not change, host has to react 
> to this.

I don't think that this happens if there is a common
wired link between the ARs and APs  (it can only occur 
in a multilink subnet).

Is this what you meant?  
If so, should we be thinking about multi-link subnets?

I know that there is the issue of router failure.
Our solutions should definitely tolerate this.

> Or, the link, default router and prefix change at the same time.

How about we call this "subnet change" ?

> On the other hand, the link might not change (i.e., host is still 
> connectedto the same media), but the configuration parameters 
> change. For example
> router renumbering. Now host has to react to this too.

You are definitely right here, although the presence of
a new prefix will be evident if the node is already (physically)
attached.

I'm not sure that we need to deal with this though, since
this is already supposed to be dealt with in ND/RR. 


I think one of the problematic sentences was:

"For these nodes, it is also important detect if an acquired
link is new, or has already been visited"

I've changed link to subnet.  Does this help?

Greg