Hi Radhika,
I am glad to see that we all agreed mobility on H.323 is not rocket science.
On the call scenarios I did not see any conflicts with h.225 call control. Once the mobility/location issue is resolve, that is once the application knows where to route the calls. In other words, when the RAS procedures and the location updates are done, we know where to route the call, using basic h.225 call control. And it was covered in Motorola's APC 1646. By the way, I like to include the Call scenarios you identified in the H.323 annex-H document. To test out "OUR" H.323 combined contributions for the architecture.
Also see last comments below.
"Roy, Radhika R, ALARC" wrote:
Hi, Ed:
I guess that we talking about the same thing.
Who told that mobility functions are different in H.323 (IP) or other networks? The basic functionality is the same from end users' point of view.
In H.323, the H.323 (e.g., H.225.0, Q.931/932) signaling messages are used. The cellular-PSTN networks use their signaling messages. The call scenarios can be as follows:
- Mobile H.323 Terminal to Mobile H.323 Terminal
- Mobile H.323 Terminal to Fixed H.323 Terminal and vice versa
- Cellular-PSTN Terminal to Mobile H.323 Terminal (3a) and vice versa (3b)
- Cellular-PSTN Terminal to Fixed H.323 terminal (4a) and vice versa (4b)
For cases 1 and 2, mobility solutions can be provided using the H.323 mobility only (pl. see AT&T's and Nokia's contributions that deal in terms of H.323 only).
For scenarios 3 and 4, the question of interworking between H.323 (IP) and cellular-PSTN comes.
Because of H.323, we have certain constraints imposed by its architecture. For example, H.323 mobility solution may look as follows:
H.323 mobility is applicable for both wireless and wire-linemobility.
H.323 mobility is addressed in the application layer and can beimplemented to any packet-switched networks (e.g., IP, etc.).
H.323 mobility management is done using the RAS (extended toincorporate mobility) signaling scheme. RAS is usually used for the pre-call control signaling and, is completely separated from the call control (Q.931/932) signaling. However, in H.323, it is mandatory that RAS signal has to go through the gatekeeper (GK). RAS signaling can be used anytime independent of the call control scheme. In this respect, H.323 mobility can be managed anytime (before the call, during the call, and/or after the call) as it is necessary.
In H.323, Q.931/932 is used for the call control. H.245 is usedprimarily to control media (audio, video, and/or data) within a call.
The wireless or wire-line network layer (e.g., IP) can use anyscheme as appropriate for implementation of the application layer H.323 mobility.
(How will a complete end-to-end solution look like that satisfy scenarios 1, 2, 3, and 4? As an HYPOTHETICAL end-to-end solution, I would request combine the solution provided in AT&T's contribution [APC-1651] in H.323 domain and Motorola's contribution [APC-1646] in cellular/PSTN-H.323 excluding some redundant functions.
I guess that Motorola's solution does NOT address scenarios 1 and 2 adequately.
Once the RAS procedures are done, we know where to route the call using basic h.225 call control.
Motorola is not forcing any solution if one looks at the References section of APC-1646 you will see we try to us the best solutions, and sections 4.1 to 4.1.2 is based on AT&T's Document TD-9 August 2-6 1999 Berlin contribution. As the Editor of Annex-H and the lack of contributions at that time, the reference below was all I had to work with.
[1] ITU-T Recommendation H.245 (1998), Control protocol for multimedia communication. [2] ITU-T Recommendation H.323 (1999), Packet-Based Multimedia Communications Systems. [3] Internet Draft <draft-teoyli-mobileip-mvpn-02.txt> February 1999, Mobile IP extension for Private Internets Support (MPN), W. T. Teo National University of Singapore and Y. Li Nortel Networks, Inc. [4] W. Liao, Mobility Internet telephony: Mobile Extensions to H.323, INFOCOM99, New York, NY, USA, 2-6 August, 1999. [5] RECOMMENDATION ITU-R M.1073-1 DIGITAL CELLULAR LAND MOBILE TELECOMMUNICATION SYSTEMS (Question ITU-R 107/8) (1994-1997) [6] HANDOVER PROCEDURES ITU-T Recommendation Q.1005 (Extract from the Blue Book) © ITU 1988, 1993 [7] E. Martinez, Motorola, Annex H (User and Service Mobility in H.323) Proposed Architecture, APC-1560, ITU-T SG16 Q.11-15 Rapporteur Meeting, Berlin, Germany, 2-6 August, 1999. [8] H.323 Mobility Ad Hoc Group, "Terms of Reference for H.323 Mobility", Temporary Document No. 34 (Berlin) 5 August 1999
Best Regards,
Ed
The bottom line is that a solution will look like this: Add some new messages in H.323 and extend the existing H.323 messages. I guess that AT&T's APC-1651 can satisfy almost all requirements specified in Motorola's APC-1646. I hope that APC-1641 will also be able interwork with GSM/GPRS, ANSI-41, etc. The requirements for TIPHON matrix will also be satisfied. If needed, one can also use mobile IP or other schemes for implementation in the IP network layer. I am personally also interested about the location area concept as proposed by Nokia. Of course, I am waiting to see other contributions and on-going discussions.)
Hope this will clarify further.
Thanks, Radhika
-----Original Message----- From: Edgar Martinez [1] [SMTP:martinze@CIG.MOT.COM] Sent: Monday, November 01, 1999 3:14 PM To: ITU-SG16@MAILBAG.INTEL.COM Subject: Re: H323mobility:meeting
Hi Radhika,
The Annex-h document was push back to 2001.
The mobility H.323 additions is not allot of work. The mobility applications and concepts been around for long time.
I would hope the following to re-use 100% of the IP network already defined in Standards. And borrowing and applying mobile applications already defined to H.323 . Which can coexist with other mobile "SERVICES" from IETF, GSM/GPRS and even 3GPP. All on the same IP network using one access protocol preferably the H.323 access protocols. Once we have a solid IP network infrastructure which includes other "SERVICES" like: reliable IP transport, QoS, charging/billing, security, IN interworking and naming and address translations. Adding mobility and Interworking services to H.323 seems like a drop in the bucket. Now do we need to defined everything, I argue that only the parts needed to be address are common to all mobile systems.
In TIPHON document 7001 we provide a matrix of existing mobile Services on networks. Which compares the mobility aspects for terminal, user and service mobility.
In the same token if one looks at H.323 interworking IN on IP, ISDN, ISUP and HTTP services, they're focus is on re-using common elements. And one access protocol H.323, why is mobility any different?
Ed
"Roy, Radhika R, ALARC" wrote:
Hi, Ed and All,
I fully agree with you that we need to address both together to have an end-to-end solution. In fact, this is also AT&T's goal because we want
to
provide services on end-to-end basis consisting both cellular-PSTN/ISDN
and
H.323 (IP).
In fact, you have covered some functions: "HomeZone ID, VisitedZone ID,
Home
Aera and Visited Area." That is, we are NOT considering any generalized solution that excludes the fundamental concept of "Zone" and "Domain" of H.323.
The point is that we can consider more functions as much as we want, but
we
still needs to work within the framework of H.323.
When I say that we need to provide solution in the context of H.323, I
mean
that we need to find solution in the framework of H.323 as much as we
can
(that might include all abstractions of cellular-PSTN network, if
possible,
in H.323 as well). It provides a systematic way to solve the problem step-by-step.
Once we complete this first step, we then apply this solution in the
conext
of cellular-PSN/ISDN-H.323 (IP). We will able to test and examine how
far we
have been able to satisfy the requirements in the first step. If we do
not
satisfy all requirements, then we need to extend the functionalities of
the
first step.
Let us examine the case of location area (LA). As I mentioned in my
earlier
email, LA can be considered in H.323 as a subset of zone without
relating to
the LA of the cellular-PSTN network. In this situation, LA defined is
H.323
may not be useful to provide interoperability between cellular-PSTN and H.323 (IP). Should we not abstract the LA in H.323 in such a way that
also
provides interoperability in the context of both cellular-PSTN and H.323 (IP)? Does not the two-step process provide better granularity to have
the
complete solution?
H.323 Annex H has two primary sections: H.323 Mobility and
Interoperability
(H.323-Cellular-PSTN).
When I say two-step process, I mean two-step working mode of Annex H. However, we will standardize the H.323 Annex H after completing both
H.323
Mobility and Interoperability (H.323-Cellular-PSTN).
Did we not agree that we may not be able to visualize all functions to
start
with and we may have to come back to add more functions as we go more
deep
into the solution? Kindly see AT&T contributions APC-1651/1652/164/1665
how
many MORE functions that we need to define even in H.323. Do I start
arguing
right now why you are not including all function right away?
I have not even written a contribution considering cellular-PSTN-H.323
(IP)
interworking yet.
Hope this will clarify further.
Best regards, Radhika
-----Original Message----- From: Edgar Martinez [1] [SMTP:martinze@CIG.MOT.COM] Sent: Monday, November 01, 1999 12:34 PM To: ITU-SG16@MAILBAG.INTEL.COM Subject: Re: H323mobility:meeting Importance: High
Dear Roy and Jaakko,
The information in Annex-H Draft all came from both TD16 and TD42b. The HomeZone ID and VisitedZone ID are new concepts used for H.323 mobility which is related to the functions we all agreed was needed to provide mobility for the application point of view. The new definition should not clash with the meaning of ZONE or Domain in H.323. In any event, we need to defined the properties of the HomeZone ID, VisitedZone ID, Home Aera and Visited Area. In the context of H.323 mobility and Interworking with PSTN.
New subject:
Our first goal is to define a mobility architecture in the context of
H.323.
Our second goal is to interworking between the packet-based H.323
mobility
architecture and circuit-switched based cellular-PSN/ISDN mobility architecture.
Motorola is looking at a full end-to-end fixed, wireless and mobile full IP solution. Which includes interworking as a major basic requirement.
We are not defining or designing a new IP system. Our job is simply to add to the existing IP infrastructure wireless
access
and the mobility applications. And support interworking with the
legacy
mobile systems. We and others are looking at providing the full
package.
If we do not address the full solution now, I feel we leave the door open for Hybrid systems, so-called network overlay or work arounds.
I will oppose that Annex-H is complete. If we do not address the interworking sections (as proposed in the TOR) within the same timeframe that we
are
defining
how to add the mobility functions to H.323.
Regards, Ed
"Roy, Radhika R, ALARC" wrote:
Hi, Ed, Jaakko, and All,
In H.323, zone and domain are well defined.
If we can solve mobility problems within the framework of H.323 as
far
as
practicable, we do not need to create new terminology in the context
of
H.323 for now. Contributions (APC-1651/1652) have also been
presented
also
how H.323 mobility problems can be solved with the context of zones
and
domains.
I understand that location area (LA) is also used in the cellular
wireless
network.
If the new terminologis like location area (LA) are created for
interworking
between cellular-PSTN and IP networking environments, we definitely
need
to
look into how "LA" is fitted in the context of zone or domain.
However,
zone
and domain are the fundamental concept of H.323 that always needs to
be
related.
Our first goal is to define a mobility architecture in the context
of
H.323.
Our second goal is to interworking between the packet-based H.323
mobility
architecture and circuit-switched based cellular-PSN/ISDN mobility architecture.
In H.323, a zone may consist of many networks (e.g., many IP
subnetworks).
Do we need to create LAs within a zone? Will the LA be a good fit
with
that
of cellular network for interworking at this point of time because
we
have
not yet solved the basic problem in the context of H.323?
I had some initial discussion with Jaako in the last Red Bank
meeting,
but
we could not complete our discussion. My personal view has been that
we
may
need something like LA to further optimize the mobility problem
within a
zone. For example, paging may be one of the reasons. However, I have realized that this LA concept may be more important in the context
of
H.323
(IP) and cellular-PSTN interworking. So, my feeling has been that we
may
need more functions similar to LA when interworking is concerned
(Motorola's
contribution APC1646 is an example). The idea has been that we
should
consider all those extensions in H.323 mobility architecture when we
deal
with interworking (second phase).
Definitely, LA concept has some merits and we need to discuss it.
Best regards, Radhika R. Roy AT&T
- 1 732 420 1580
rrroy@att.com
-----Original Message----- From: jaakko.sundquist@NOKIA.COM [SMTP:jaakko.sundquist@NOKIA.COM] Sent: Monday, November 01, 1999 7:23 AM To: ITU-SG16@MAILBAG.INTEL.COM Subject: Re: H323mobility:meeting
Hi Ed,
I haven't read your draft yet, but I just want to make a short
comment
on
the definitions that you proposed. You mention the concepts of HomeZone ID and VisitedZone ID. This
implies
already to a certain architecture, namely one where the "home
area"
and
"visited area" of a User are defined to be identified with the
accuracy of
one zone. In my contribution to the Red Bank meeting (APC 1659) I
proposed
similar "home area" and "visited area" concepts based on
Administrative
Domains, which in my mind makes more sense as the Domains have so
far
in
H.323 been the entities that are responsible for maintaining any information of their users. So I propose that we think about the architecture first before
defining
these terms.
- Jaakko Sundquist
In a hole in the ground there lived a hobbit.Not a nasty, dirty, wet hole, filled with the ends of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing in it to sit down on or to eat: it was a hobbit-hole, and that means comfort.
-----Original Message----- From: EXT Edgar Martinez [1][mailto:martinze@cig.mot.com] Sent: Monday, November 01, 1999 3:33 AM To: ITU-SG16@mailbag.cps.intel.com Subject: H323mobility:meeting
Dear All, I have put together the first proposed draft andoutline
for H.323 Annex-H. You can pick-up a copy in: http://people.itu.int/~emartine/temp/
Editor's Special Note: The interworking referredin
this
annex is the interwork of legacy systems to H.323 systems.
Not
to
be confused with interworking H.323 systems to circuit
switched
hybrid
systems or circuit switched adjuncts. The work proposed
therewith,
does not impact the legacy systems or impose new requirements to
the
Legacy systems to support H.323 terminals or H.323 systems.
Need to add more sections to the Annex-H tocomply
with
TOR e.g., Interworking:
Network interworking connections between H.323 systems and mobilenetworks
(e.g., GSM, ANSI 41, ...) connections between mobile H.323 systems and PSTN
or
other
networks.
Terminal interworking Use of non-H.323 mobile terminals (e.g., GSMhandset,
H.324 terminal, H.320 terminal, etc.) to communicate with H.323
systems.
Tandeming minimisation Non-transcoding of media streams Also, it would be nice if we can add to the the defiention section: Home Location Funtion (HFL) Vistor Location Funtion (VFL) Authentication user Funtion (AuF) HomeZone ID (HZid) VisitedZone ID (VZid) -- Edgar Martinez - Principal Staff Engineer Email mailto:martinze@cig.mot.com FAX 1-847-632-3145 - - Voice 1-847-632-5278 1501 West Shure Drive, Arlington Hgts. IL 60004 Public: TIPHON & Other Stds -http://people.itu.int/~emartine/ Private:TIPHON & Other Stds - http://www.cig.mot.com/~martinze/
-- Edgar Martinez - Principal Staff Engineer Email mailto:martinze@cig.mot.com FAX 1-847-632-3145 - - Voice 1-847-632-5278 1501 West Shure Drive, Arlington Hgts. IL 60004 Public: TIPHON & Other Stds - http://people.itu.int/~emartine/ Private:TIPHON & Other Stds - http://www.cig.mot.com/~martinze/
-- Edgar Martinez - Principal Staff Engineer Email mailto:martinze@cig.mot.com FAX 1-847-632-3145 - - Voice 1-847-632-5278 1501 West Shure Drive, Arlington Hgts. IL 60004 Public: TIPHON & Other Stds - http://people.itu.int/~emartine/ Private:TIPHON & Other Stds - http://www.cig.mot.com/~martinze/
-- Edgar Martinez - Principal Staff Engineer Email mailto:martinze@cig.mot.com FAX 1-847-632-3145 - - Voice 1-847-632-5278 1501 West Shure Drive, Arlington Hgts. IL 60004 Public: TIPHON & Other Stds - http://people.itu.int/~emartine/ Private:TIPHON & Other Stds - http://www.cig.mot.com/~martinze/