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Re: [802.21] Discussion on Information Service



Gupta, Vivek G wrote:

> Maybe we should try to focus more on such aspects and also keep
> discussions technical. 
> What are the network information elements that help in handovers? 

The answer could be many. One way or another, the handover decision 
maker may use all sorts of network information to help in handover. But 
we have to keep in mind that handover is a big feature in a mobile 
system and there are a number of entities across layers and clouds that 
are involved in making handover happen and 802.21 is just one piece of 
the puzzle. Therefore, even after we agree that an IE is useful for 
handover, we have to ask ourselves why 802.21 is the right mechanism to 
carry/provide this IE to the h/o decision logic. To automatically assume 
that 802.21 be the sole provider/carrier of all handover relevant 
information to the decision maker would be a mistake.

> How? I guess the how (reasoning) part is not well described in current draft
> and that gives rise to many questions. We may need to review each of the
> IEs and come up with explicit use cases/reasoning as to how they help
> during handovers. That may also help with understanding the business
> case/reasoning for deploying some of this, even though that part is
> outside the specification.

ditto.

regards,
-Qiaobing

> 
> There are also some issues we need to resolve. If 802.21 provides access
> to neighbor graphs/reports for multiple networks (802.11, 802.16,
> Cellular) in what format should these reports be provided?
> 
> Best Regards,
> -Vivek
> 
> 
> -----Original Message-----
> From: stds-802-21@ieee.org [mailto:stds-802-21@ieee.org] On Behalf Of
> Qiaobing Xie
> Sent: Sunday, August 21, 2005 2:22 PM
> To: Koora Kalyan Com Bocholt
> Cc: STDS-802-21@listserv.ieee.org; 802-21-MEMBERS
> Subject: Re: [802.21] Discussion on Information Service
> 
> All,
> 
> I think this discussion is very important at this point. Indeed, we have
> 
> talked about the scope and other issues before (a lot), but for one I am
> 
> not 100% satisfied with what we have concluded. I have also heard from 
> multiple sources outside of 802.21 that the current scope of 802.21 is 
> both too big and ambiguously defined. For example,
> 
>      - provide generic link layer intelligence and other network
>        related info to upper layers to optimize handovers between
>        heterogeneous media
> 
> It is easy to argue that 802.21 is in a good position to provide generic
> 
> link layer intelligence to upper layers for handover. But for providing 
> "other network related info to upper layers" for handover, I am not so 
> sure. People can rightly question why we think 802.21 is better suited 
> than other mechanisms/protocols in providing network info to upper 
> layers for optimizing handover.
> 
> regards,
> -Qiaobing
> 
> Koora Kalyan Com Bocholt wrote:
> 
>>Hello All,
>>
>>after taking part in couple of telcons, I feel that there is a 
>>strong need to raise a disucussion on the .21 Information Service.
>>In particular I feel that there is an urgent need to fix the basic
>>information set at this point before proceeding to different
>>standardisation bodies.
>>
>>As a starting point, I am just putting couple of basic points 
>>together to have a common understanding in discussion.
>>I would be happy to see your comments/opinions/ideas/suggestions
>>to reach a common consensus on this matter.
>>
>>with best regards,
>>Kalyan Koora
>>
>>+-----------------------------------------------------------------+
>>|                Discussion on Information Service                | 
>>+-----------------------------------------------------------------+
>>
>>I.   What is 802.21 MIH scope?
>>II.  Handover of what?
>>III. Present Handover mechanisms
>>IV.  How to continue?
>>
>>I. What is 802.21 MIH scope?
>>
>>   - provide generic link layer intelligence and other network 
>>     related info to upper layers to optimize handovers between 
>>     heterogeneous media
>>
>>   - enhance and/or support handovers between heterogeneous 
>>     media
>>
>>   - maximize service continuity
>>
>>II. Handover of what?
>>
>>  - A session / an application running over a media to other media
>>
>>  - session/service continuity is desired
>>
>>  If we are speaking about a "session", then we mean 
>>  "running application".
>>
>>  If we are speaking about "handover of a running session" from 
>>  one to other media, it is a "must" that the minimum requirements 
>>  of the session are available at the other media.
>>
>>III. Present Handover mechanisms
>>   Present well known handover mechanisms (like MIP):
>>   - select one media for all sessions
>>   - do not do load-balancing
>>   - neither care about application needs nor take care of
>>     user or network preferences dynamically
>> 
>>  The evolving mechanisms are aiming to enable this.
>>  To assist these intelligent handover mechanis (what 802.21 is
>>  aiming at), it is important to have following information 
>>  as early as possible:
>>
>>  1. what applications are running on the terminal or what
>>     sessions are build up
>>  2. If a new session/application is started, what are its needs
>>  3. what medias are present in the terminal and what are their
>>     capabilities
>>  4. what are the reachable networks in the vicinity and
>>     what are their capabilities.
>>  5. what application support is provided by the networks
>>  6. Last but most, what are the user and operator preferences.
>>
>>  If these points are agreed, then comes the question:
>>  Taking the above mentioned points into consideration, if 802.21 
>>  likes to enhance the handover mechanisms, what is the 
>>  information envisaged by the .21?
>>
>>IV. How to continue:  
>>   
>>   To refine/enhance/modify I feel, there is an urgent need to
>>   take a look at the IS, in particular the basic set.
>>
>>   What is needed?
>>
>>   - shall we define a unique basic set for all standards, to be
>>     media independent?
>>   
>>   - shall we take the existing basic set, think of scenarios
>>     where this is needed and put them as essential and remove
>>     the things which are not needed?
>>
>>   - shall we define completely new set for each and every standard
>>     just like independent SAPs?
>>   
>>+-----------------------------------------------------------------+
> 
> 
>