Re: [802.21] Discussion on Information Service
I fear the commenter is missing the entire objective of IEEE 802.21.
It is the function of 802.21 to be exactly what the commenter is intimating
(at least from the air interface side): a media independent method of
exposing the lower layer (PHY & MAC) information elements of air interfaces
(802.16, 802.11, 802.??, etc...) so that higher layer handover policy
managers can use the information to prosecute handovers; and to take the
resulting actions of handover policy managers and translate them into
appropriate air interface transactions. The entire objective of 802.21 is to
create a common information language so that handover policy managers do not
have to have differentiated mechanisms and language to work with each of the
air interface types. Also, 802.21 has the added benefit of helping air
interface groups adding mobility to their standard by highlighting necessary
information elements, metrics, and triggers typical for handover.
So 802.21 is supposed to do exactly what the commenter seems worried that it
is doing.
Thanks,
Phillip Barber
Huawei
----- Original Message -----
From: "Qiaobing Xie" <Qiaobing.Xie@motorola.com>
To: "Gupta, Vivek G" <vivek.g.gupta@INTEL.COM>
Cc: "Koora Kalyan Com Bocholt" <kalyan.koora@SIEMENS.COM>;
<STDS-802-21@listserv.ieee.org>; "802-21-MEMBERS"
<STDS-802-21-MEMBERS@listserv.ieee.org>
Sent: Monday, August 22, 2005 2:04 PM
Subject: 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?
>>> +-----------------------------------------------------------------+
>>
>>
>>
>