Subject: [mobile-ip] question on L2 triggers draft

From: Nakhjiri Madjid-MNAKHJI1 <[email-masked]>
Date: Wed, 5 Dec 2001 16:08:02 -0600

Alper,

Nice informative draft. I have one question on the L2 handover section (4.1)
You say 

"When APs supporting multiple radio technologies on a single subnet,
interoperability suffers if there is no L2-independent way of reporting
on link movement."

Would you care to elaborate? 
Say a WLAN AP-cellular AP case, do you mean the movement has to be reported
at L3 even if the two APs belong to the same subnet?

Regards,
Madjid

-----Original Message-----
From: Alper E. YEGIN [mailto:[email-masked]]
Sent: Sunday, December 02, 2001 2:14 AM
To: [email-masked]
Subject: [mobile-ip] L2 triggers draft

Folks,

New version of L2 triggers draft is available:

http://www.ietf.org/internet-drafts/draft-manyfolks-l2-mobilereq-01.txt

Supporting Optimized Handover for IP Mobility - 
Requirements for Underlying Systems 

   Abstract 
    
   A critical factor in achieving good performance for IP mobility 
   protocols is the design of L2 handover. Handover occurs when a 
   Mobile Node moves from one radio Access Point to another. If the new 
   radio Access Point is associated with a new subnet, a change in 
   routing reachability may occur and require L3 protocol action on the 
   part of the Mobile Node or Access Routers. If no change in subnet 
   occurs, the Access Point may still need to take some action to 
   inform the Access Router about a change in on-link reachability. In 
   either case, prompt and timely information from L2 to the parties 
   involved about the sequencing of handover can help optimize handover 
   at the IP level. This draft discusses requirements for an L2 
   handover protocol or API to support optimized handover. 

Enjoy.

alper

---

From: "Alper E. YEGIN" <[email-masked]>
Date: Wed, 5 Dec 2001 21:41:19 -0800

Hi Madjid,

This is James Kempf, Alper is lending me his machine.

I think I wrote that. What I had in mind was the following situation.
Suppose I've got a subnet with 802.11 and Bluetooth access points. Having a
way that the access points could report movement to the access router would
faciliatate intra-subnet movement, for example, ARP cache flushing.

                    jak