Subject: Re: [MOBILE-IP] Handoff framework [Was Re: [MOBILE-IP] Anothernovicequestions!]

From: [email-masked]
Date: Tue, 15 Aug 2000 00:27:07 -0500

Pat,
I was not proposing each wireless standard body making Mobile IP work. On the
contrary, I am proposing that each wireless standard body should map its Access
Network specific link layer into a common Abstract link layer defined by Mobile
IP WG. This will free Mobile IP from specific Link Layer dependent.

This can be achieved by implementing a common link layer protocol extension.

Without this common Link Layer protocol, each FA implementation will be
dependent on each specific Link Layer.

That's all I am trying to say. Hope I am not mislead you. God know how you come
up so much conclusion.

---Yingchun.

"pcalhoun/@eng.sun.com" <Pat.Calhoun on 08/14/2000 03:40:44 PM

Please respond to "[email-masked]" <[email-masked]>

Sent by:  "[email-masked]" <Pat.Calhoun

To:   Yingchun Xu/MW/US/3Com
cc:   [email-masked]
Subject:  Re: [MOBILE-IP] Handoff framework [Was Re: [MOBILE-IP]
      Anothernovicequestions!]

> I agreed with Jim. In fact, the approach has been used to some extent in 3G
> cdma2000 wireless network.
>
> In general, there are two approachs to abstract an Access Network:
> 1. Abstract Link Layer Protocol: Defining an common link layer protocol to
> extend various Access Network to FA.
>  By doing this, an FA will only need to understand the Abstract link layer
> protocol (or Abstract Access Network).
> Each Access Network will be
> responsible for translating (or mapping) its specific link layer to the
> Abstract link layer.
>
> In 3G cdma2000, the RP interface protocol (to some extent) is an extension of
> cdma2000 link layer.
>
> 2. Link Layer Specific FA: This will make every Access Network has its own
> specific FA. The FA will be fully
> knowledgable of a specific link layer (or Access Network).  This method
> tries to abstract Access Network
> at network layer so that from HA point of view, all Access Network are same.
> Unfortunately, it makes Mobile IP
> depending on specific link layer.
>
> Method 1 is prefered since it makes Mobile IP independent of any specific
> link layer protocol (but still dependent of
> the common Abstract link layer).
>
So, let's see if I get this correct.

You propose that each wireless standard try to figure out how to get Mobile IP
working correctly, as opposed to Mobile IP providing a set of tools for the
wireless standards people to use.

Do you not believe that the IETF is where any Mobile IP work should be done?
Do people really want to see solutions like the 3G ext, where PPP is carried
in GRE, and god knows what other standard body comes up with, as opposed to a
*single* nice clean solution?

I much prefer #2 above, but I do not like the way you've put it. How about:

"2. The Mobile IP WG will develop a single fast handoff strategy, that takes
advantage of certain wireless technology capabilities. The document will
include support for complex air interfaces (e.g. ones that provide air
interface measurements), and simpler ones (e.g. ones that do not provide such
measurements)."

PatC

---

From: Ajoy Singh <[email-masked]>
Date: Tue, 15 Aug 2000 11:28:29 -0500

Hi All,
I also agree with the idea of link layer trigger being used to trigger
mobile/IP handover. I also think it is possible to define a common link
layer extension to make FA implementation independent of link layer details.
I guess it might be enough to define a link layer primitive which will be
sent from link layer to network layer whenever handover event is detected.
The handover draft can define what it expects in the link layer handover
primitive.  It will be job of the respective link layers to provide the
information required by handover primitive to layer 3. This way the foreign
agent implementation will be independent of link layer. I am not in favor of
proposing complete new RP like protocol between radio access network and
foreign agent as generic protocol might not be suitable to different access
technologies and moreover Mobile/IP may not be right place to define such
link layer protocol extension. In case of CDMA 2000, RP may be extended to
accommodate information required by handover primitive. Any suggestions ?
regards,
ajoy

-----Original Message-----
From: IP Routing for Wireless/Mobile Hosts (mobile-ip)
[mailto:[email-masked]]On Behalf Of
[email-masked]
Sent: Tuesday, August 15, 2000 12:27 AM
To: [email-masked]
Subject: Re: [MOBILE-IP] Handoff framework [Was Re: [MOBILE-IP]
Anothernovicequestions!]

Pat,
I was not proposing each wireless standard body making Mobile IP work. On
the
contrary, I am proposing that each wireless standard body should map its
Access
Network specific link layer into a common Abstract link layer defined by
Mobile
IP WG. This will free Mobile IP from specific Link Layer dependent.

That's all I am trying to say. Hope I am not mislead you. God know how you
come
up so much conclusion.

---Yingchun.

You propose that each wireless standard try to figure out how to get Mobile
IP
working correctly, as opposed to Mobile IP providing a set of tools for the
wireless standards people to use.

Do you not believe that the IETF is where any Mobile IP work should be done?
Do people really want to see solutions like the 3G ext, where PPP is carried
in GRE, and god knows what other standard body comes up with, as opposed to
a
*single* nice clean solution?

"2. The Mobile IP WG will develop a single fast handoff strategy, that takes
advantage of certain wireless technology capabilities. The document will
include support for complex air interfaces (e.g. ones that provide air
interface measurements), and simpler ones (e.g. ones that do not provide
such
measurements)."

PatC