RE: [802.21] Network Controlled Handover and IS
Vivek,
A couple points on bullet 4)
-----Message d'origine-----
De : stds-802-21@ieee.org [mailto:stds-802-21@ieee.org] De la part de Gupta, Vivek G
Envoyé : jeudi 25 août 2005 12:13
À : Junghoon Jee; stefano.faccin@NOKIA.COM; STDS-802-21@listserv.ieee.org
Objet : RE: [802.21] Network Controlled Handover and IS
I don't have any doubt that 802.21 needs to support network initiated handovers. Many networks such as 3GPP and even WiMax are more operator controlled type networks and we need to accept that and support that in the 802.21 standard. Of course terminal initiated handovers shall always be supported. So what are the additional requirements?
1] Measurements type dynamic info:
As mentioned earlier different access technologies already provide these in some form (especially those that already support intra-mobility, since the same measurements are required in those cases as well).
2] Application requirements and User/Terminal policy information:
Not sure if all of this needs to be handled by 802.21 and even then if and can this be standardized. One way to do this would be to have some commands/events for exchange of vendor specific/app specific type messages and leave it at that. We may need clear requirements for something more specific.
3] Generic Handover commands/message exchanges:
This would be a set of exchanges between client and network for initiating handovers and managing the handover process (failure cases as well). These could be generic across different access networks and could go over L3 (most likely) or L2 (let's not preclude for now) as well.
These have already been defined in some preliminary form in current draft.
4] Resource query and query of network capabilities:
If a network entity decides to initiate handover, it may need to query access networks about available resources/QoS levels etc. as part of handover decision making. Some of this functionality is also included in current 802.21 draft and we can evolve this to comprehend other different cases.
(Please also note that resource query as an option was considered for a long time during proposal stage in 802.11-Tgr but was eventually rejected for intra-mobility cases, so it's not clear if we may need to do, that much more here beyond existing capabilities in different access networks that already support intra-mobility.)
<<[Eric Njedjou] an optimal handover, can not happen without considering availability of resources on target: GSM and UMTS handover are based on that important check. Therefore i for one believe that operators would not be able to implement TGR specifications as the current draft stand because they won't be able to verify resource availability in the handover process. When inter-system comes into play, the check will consist making sure the the target poA has the resource/QoS that satisfied the handed over sapplication>>
Anything else?
Please keep the good thoughts rolling so that we can get this very important aspect of 802.21 discussed and key requirements identified.
Best Regards
-Vivek
-----Original Message-----
From: stds-802-21@ieee.org [mailto:stds-802-21@ieee.org] On Behalf Of Junghoon Jee
Sent: Thursday, August 25, 2005 2:10 AM
To: stefano.faccin@NOKIA.COM; STDS-802-21@listserv.ieee.org
Subject: RE: [802.21] Network Controlled Handover and IS
Stefano,
> [Junghoon]
> I tend to agree about the scenario that Stefano mentioned as a general
> application of MIH.
> However, I have some concern regarding the network-initiated
> inter-technology handover.
> To support not one or two mobile terminals, overloading of MIH
> _handover_ control entity by enormous MIH events and commands...
> IMO, it would be better to let a mobile terminal have a brain about
> inter-technology handover decision.
>
>
> [[Stefano] ] I surely don't disagree that there are challenges.
> however, there are at present requirements coming from some 3GPP
> operators to enable such network controlled handoffs, and I believe
> 802.21 should enable them. If one wants to use them or not, that's up
> to the manufactures and operators. If we do not enable the scenarios
> for which we have requirements, we risk to restrict 802.21
> applicability to the real world.
Thank you for good information.
I did actually guess there's coming a requirement from the network operator side.
Hopefully, it needs to be resolved.
Possibly, we can list-up some requirement in providing network-controlled MIH handover.
Regards,
Junghoon