Subject: RE: [seamoby] draft-ietf-seamoby-paging-problem-statement-01.txt

From: "Karim El-Malki (ERA)" <[email-masked]>
Date: Fri, 16 Feb 2001 23:18:49 +0100

Hello James

> >> The problem remains the same regardless of whether network assisted
> >> or mobile assisted handoff is used. The point is that the mobile
> >> only sees a change in paging area due to the L2 support 
> for signalling
> >> when it crosses a paging area boundary, not when it 
> crosses a subnet
> >> boundary. Hence, if there are multiple subnets per paging area, the
> >> mobile does not know when it crosses a subnet boundary, and hence
> >> it cannot perform a MIP registration.
> >
> >You're saying that when a MN crosses a subnet boundary it 
> can't perform
> >a MIP registration? Isn't that specific to the network 
> assisted handoff
> >techniques you have based the draft on? You could cross a 
> subnet, get some
> >kind of advertisement and then Register over whatever 
> channel is available.
> >
> 
> 
> No, I'm saying that when it crosses a subnet boundary it can't perform
> a paging area registration. 

OK, you wrote MIP registration in your last sentence above.

>Unless the paging area and the subnet
> are exactly the same, and this is impossible to guarantee in realistic
> deployments.

Does this justify the need for IP paging?
If you've done a MIP registration you're reachable and you don't need to
be paged at IP level but only at L2 level.

Regards
/Karim