H.323 Annex I

Roy, Radhika R, ALARC rrroy at ATT.COM
Fri Dec 24 10:05:50 EST 1999


Hi, Chris:

We have an H.323 Ad Hoc Mobility Group to perform this work. We have been
discussing this for almost a year why we need H.323 mobility. All wire-line
and wireless vendors and many service providers are also a part of it. All
of them brought contributions to extend the H.323 protocol for mobility.

I am very much surprised to see your comments. I guess that all people who
are working to address this issue will also feel the same.

I do not want to confuse anyone by making a simple statement that will make
you feel why we need extensions in H.323 for mobility. So many papers have
been published by many researchers across the world for extension of H.323
for mobility. One of the excellent papers had been published in INFOCOM'99
referred in AT&T's contribution as well. I would suggest to kindly read this
paper first before making any comments like "misconception" or others, etc.
May be I have not been able to understand your points. I'd would also
suggest to attend the discussion of the Ad Hoc mobility conf. calls.

Finally, I'd only suggest to examine how a GK will account the resources
when an H.323 mobile moves from one place to another. The resources of one
place have to be de-allocated in one place, while the resources in another
place are to be allocated. When people think about resources, these
resources are in terms of the H.323 layer. It does not matter how you think
about the zone whether it is linked to physical locations, IP domain, or
something else.

May be you might have a better solution to deal the mobility. May we suggest
to bring contributions to solve the H.323 mobility problems that you might
think to be appropriate.

Best regards,
Radhika

> -----Original Message-----
> From: Chris Wayman Purvis [SMTP:cwp at isdn-comms.co.uk]
> Sent: Friday, December 24, 1999 8:27 AM
> To:   Roy, Radhika R, ALARC; Mailing list for parties associated with
> ITU-T Study Group 16
> Subject:      Re: H.323 Annex I
>
> Radhika, All,
>
> I've finally managed to read that contribution, and it seems to me that
> the
> requirement for a mobile H.323 protocol arises entirely out of the
> misconception that gatekeeper zones are necessarily linked to physical
> locations or IP domains.  Remove that assumption and I am still completely
> baffled as to why any protocol above the network layer is required.
>
> I will look at the MTD contributions when I find time (which is
> depressingly
> short for this sort of activity at the moment), but would be glad of
> anybody's
> simple explanation of why H.323 mobility is required without the above
> assumptions on gatekeeper zones.
>
> Regards,
> Chris
>
> "Roy, Radhika R, ALARC" wrote:
> >
> > Hi, Chris:
> >
> > I guess that you have missed all discussions and contributions related
> H.323
> > mobility (SG16 meeting in May'99, Berlin Aug'99, and Red Bank NJ
> Oct'99).
> >
> > H.323 is in application layer.
> >
> > IP/IPX is in the network layer.
> >
> > Radio/ATM is in the link layer.
> >
> > Mobility may have an impact in all layers. If the link layer mobility is
> > transparent to the network layer, nothing should be done in the network
> > layer. Similar is the case for others.
> >
> > When the mobility has an impact in the H.323 layer resources, we need to
> > take into account in the H.323 layer.
> >
> > How does the H.323 mobility work?
> >
> > Please see AT&T contributions - APC-1651 provided in the Red Bank
> meeting.
> > The 70-page contribution has proposed a complete solution for H.323
> > mobility. There are contributions as well.
> >
> > Hope this will clarify your questions.
> >
> > Best regards,
> > Radhika
> >
> > > -----Original Message-----
> > > From: Chris Wayman Purvis [SMTP:cwp at ISDN-COMMS.CO.UK]
> > > Sent: Wednesday, November 24, 1999 4:31 AM
> > > To:   ITU-SG16 at MAILBAG.INTEL.COM
> > > Subject:      Re: H.323 Annex I
> > >
> > > All,
> > >
> > > Might I be permitted to attempt to summarise Mr Roy's mail while
> asking my
> > > own
> > > question (my apologies to Mr Roy if I've misunderstood his point!)?
> > > I'm not an expert on Mobile IP.  However, I don't understand why there
> is
> > > anything at all involved in H.323 mobility beyond making the statement
> "In
> > > IP
> > > networks, mobility issues are handled by using Mobile IP", and
> expecting
> > > users
> > > of other transports (IPX, native ATM etc) to make their own
> arrangements.
> > > So, the question: Why is the effort on mobility required?
> > > Obviously if this question is answered in contributions that I've
> missed,
> > > I'll
> > > be happy with a reference rather than a full explanation on the list!
> > >
> > > Regards,
> > > Chris
> > > --
> > > Dr Chris Purvis -- Development Manager
> > > ISDN Communications Ltd, The Stable Block, Ronans, Chavey Down Road
> > > Winkfield Row, Berkshire.  RG42 6LY  ENGLAND
> > > Phone: +44 1344 899 007
> > > Fax:   +44 1344 899 001
>
> --
> Dr Chris Purvis -- Development Manager
> ISDN Communications Ltd, The Stable Block, Ronans, Chavey Down Road
> Winkfield Row, Berkshire.  RG42 6LY  ENGLAND
> Phone: +44 1344 899 007
> Fax:   +44 1344 899 001



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