Re: [802.21] [Mipshop] Re: Architectural Considerations for Handover InformationServices

[Subir Das <subir@research.telcordia.com>]

Title:

Hong-Yon Lach wrote:

From: Subir Das <subir@research.telcordia.com>
Date: Thu, 20 Oct 2005 13:51:26 -0400
To: Hong-Yon Lach <hong-yon.lach@MOTOROLA.COM>
Cc: <STDS-802-21@listserv.ieee.org>
Subject: Re: [802.21] [Mipshop] Re: Architectural Considerations for Handover
InformationServices (was: Re: CARD Discussion Query Discussion)



Hong-Yon Lach wrote:

    

I think it is not just about how dynamically the information database needs
to be updated, it is also about how dynamically the mobile terminal needs to
consult the information and how often its environment changes due to its
movement. I fail to envisage a system that is so deterministic that I can
take comfort to ignore timing issues.

      

    I agree with you that  how often mobile needs to contact the IS is
an important considertaion.
    But  what is that frequency?  Do you envisage a system that requires
a query  ~ msec while
    performing the heterogeneous handover?

    

No, but the moment the mobile terminal feels that it needs the info, it will
expect to have it quickly (IMO).

     Correct, but I would assume this will happen before the handover decision/network selection.
   

Let's say I have a completely wrong assumption of what IS is for. Based on
all these exchanges, I can only conclude that the IS provides a means to
query information from a rather static database; the use may be helpful but
is not required for the purpose of handover; it is not clear where and how
the database obtains the information; it is not clear whether the
information can already be obtained by existing means.

      

      Are we not considering the  heterogeneous environment here?
Existing systems may have such  information
      available but they cann't provide other network information.  What
we are trying to provide here is a mean such
      that  user can query the network  information  not only for the
connected network but also for other networks.
      Do you think such information is not  required/helpful for
heterogeneous handover?  The poplulation of
      database is  another area and  as far as I understand  this is out
of scope. 
     
    

I did not say that such information is not needed; I said that for certain
HO and mobility management scheme IS may not be needed. That is, there are
other ways to get such information. One example is that such information
exchange can be (integral) part of the mobility management protocol with a
mobility manager overseeing the heterogeneous networks.

     Yes, there are several ways one can collect such  information  but I don't know  of  any standard 
      method that exists today and existing mobility protocols  can make use of it.  Are not we trying
      to standardize such a method?  To me, your example mobility  manager is similar to the
      handover/policy/network selection engine that we all  believe is needed  along with  the 
      existing mobility protocol to optimize the handover performance. Extending existing  mobility
      protocols to support such functionalities is not a  good idea, IMO.