Subject: [clue] CLUE use cases comment

From: "Cole, Jim (HP Visual Collaboration R&D)" <[email-masked]>
Date: Fri, 4 Mar 2011 01:25:07 +0000

Hi,

Thinking about the current set of multistream use cases, it seems that we also want to cover situations in which a single endpoint is connected to infrastructure such as a conferencing bridge, with no other endpoints present.

For example, a multistream endpoint such as a three-screen telepresence room system may connect to a centralized multipoint conferencing system without any other participants being connected. In addition, the conferencing system may call an endpoint. Such situations may arise by deliberate intent of users initiating such a connection. They may also arise incidentally when, for example, the system dials multiple endpoints to start a scheduled conference, but only one answers. Typical considerations of telepresence experience are not in view, because there is no other physical location, but the multistream nature of the endpoint and infrastructure still need to be established, and capabilities of each determined.

Perhaps this is a special case of a multipoint meeting, but it may include other situations, as well. For example, if the far "site" is a recording subsystem. Would it make sense to cover this possibility?

Regards,
Jim Cole

---

From: "Espen Berger (espeberg)" <[email-masked]>
Date: Fri, 4 Mar 2011 09:50:15 +0100

I think it's natural to be aware of call handling use cases to verify
that our models are useful in multiple scenarios. 

I think it's useful to group information and features into three areas 

Multi stream and layouts
* How to send and receive multiple media streams 
* Spatial cameras and screens 
* Audio and video codec considerations 
* Media transport 

Call handling 
* How to enter a conference 
* Do ad-hoc invite of participant 
* ++

Conference control 
* Roster information (e.g. RFC4575) 
* Event notification 
* Commands, like mute or disconnects (XCON has a draft on commands)

As far as I understand CLUEs main focus is multi stream, cameras and
screen handling, but must also consider call handling and conference
control to make sure what we do is compatible with related standards. 

Integration with services like recording is important to understand to
make sure that we design a protocol that can be used by more services
than endpoints and conference servers. 

Cheers 

-Espen 

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of
Cole, Jim (HP Visual Collaboration R&D)
Sent: 4. mars 2011 02:25
To: [email-masked]
Subject: [clue] CLUE use cases comment

Hi,

Thinking about the current set of multistream use cases, it seems that
we also want to cover situations in which a single endpoint is connected
to infrastructure such as a conferencing bridge, with no other endpoints
present.

For example, a multistream endpoint such as a three-screen telepresence
room system may connect to a centralized multipoint conferencing system
without any other participants being connected. In addition, the
conferencing system may call an endpoint. Such situations may arise by
deliberate intent of users initiating such a connection. They may also
arise incidentally when, for example, the system dials multiple
endpoints to start a scheduled conference, but only one answers. Typical
considerations of telepresence experience are not in view, because there
is no other physical location, but the multistream nature of the
endpoint and infrastructure still need to be established, and
capabilities of each determined.

Perhaps this is a special case of a multipoint meeting, but it may
include other situations, as well. For example, if the far "site" is a
recording subsystem. Would it make sense to cover this possibility?

Regards,
Jim Cole
_______________________________________________
clue mailing list
[email-masked]
https://www.ietf.org/mailman/listinfo/clue

---

From: Peter Musgrave <[email-masked]>
Date: Fri, 4 Mar 2011 11:10:45 -0500

Hi Espen, 

I agree that the issues you are raising are important - but some of them are very specifically not in scope for CLUE. 

I think the multi-stream issues you raise are in scope. 

Issues of call handling, rosters, event notifications, floor control are all out of scope for CLUE we would look to other WGs if specific issues which require protocol work arise. 

Likewise for recording we would look to siprec. 

Regards,

Peter Musgrave

---

From: Peter Musgrave <[email-masked]>
Date: Fri, 4 Mar 2011 11:25:47 -0500

Hi Jim, 

Maybe there is a semantics issue here. I would regard a call with a user system connected to a conference mixer as a call between two endpoints. 

I see it as a two party call where each party uses CLUE-ish stuff to indicate multiple streams and capabilities and then decide on what should be send/rendered etc. 

There is an interesting issue about mixers. Do they describe the possible sources (all other cameras from all other participants) a user system could elect to receive or do they just signal that there will be e.g. 3 streams always from the same site etc. etc. At some point this gets dangerously close to floor control which CLUE is supposed to avoid. Do you think we need a use-case which highlights this issue?

Regards,

Peter Musgrave

---

From: "Charles Eckel (eckelcu)" <[email-masked]>
Date: Fri, 4 Mar 2011 09:29:52 -0800

I think there is not a need to model this separately. I regular endpoint
may do the same thing. For example, perhaps I initially make an audio
only call. Later I choose to enable my video capabilities. Then at some
point I add presentation. Of course I could have offered all of these
capabilities from the start, but that should not be mandatory.

Cheers,
Charles

> From: [email-masked] [mailto:[email-masked]] On Behalf
Of Peter Musgrave
> Sent: Friday, March 04, 2011 8:26 AM
> To: Cole, Jim (HP Visual Collaboration R&D)
> Cc: [email-masked]
> Subject: Re: [clue] CLUE use cases comment
> 
> Hi Jim,
> 
> Maybe there is a semantics issue here. I would regard a call with a
user system connected to a
> conference mixer as a call between two endpoints.
> 
> I see it as a two party call where each party uses CLUE-ish stuff to
indicate multiple streams and
> capabilities and then decide on what should be send/rendered etc.
> 
> There is an interesting issue about mixers. Do they describe the
possible sources (all other cameras
> from all other participants) a user system could elect to receive or
do they just signal that there
> will be e.g. 3 streams always from the same site etc. etc. At some
point this gets dangerously close
> to floor control which CLUE is supposed to avoid. Do you think we need
a use-case which highlights
> this issue?
> > Thinking about the current set of multistream use cases, it seems
that we also want to cover
> situations in which a single endpoint is connected to infrastructure
such as a conferencing bridge,
> with no other endpoints present.
> >
> > For example, a multistream endpoint such as a three-screen
telepresence room system may connect to a
> centralized multipoint conferencing system without any other
participants being connected. In
> addition, the conferencing system may call an endpoint. Such
situations may arise by deliberate intent
> of users initiating such a connection. They may also arise
incidentally when, for example, the system
> dials multiple endpoints to start a scheduled conference, but only one
answers. Typical considerations
> of telepresence experience are not in view, because there is no other
physical location, but the
> multistream nature of the endpoint and infrastructure still need to be
established, and capabilities
> of each determined.
include other situations, as
> well. For example, if the far "site" is a recording subsystem. Would
it make sense to cover this
> possibility?

---

From: "Charles Eckel (eckelcu)" <[email-masked]>
Date: Fri, 4 Mar 2011 09:30:01 -0800

+1

Of Peter Musgrave
> Sent: Friday, March 04, 2011 8:11 AM
> To: Espen Berger (espeberg)
> Cc: [email-masked]
> I agree that the issues you are raising are important - but some of
them are very specifically not in
> scope for CLUE.
> Issues of call handling, rosters, event notifications, floor control
are all out of scope for CLUE we
> would look to other WGs if specific issues which require protocol work
arise.
> > From: [email-masked] [mailto:[email-masked]] On Behalf
Of
> > Thinking about the current set of multistream use cases, it seems
that
> > For example, a multistream endpoint such as a three-screen
telepresence

---

From: "Cole, Jim (HP Visual Collaboration R&D)" <[email-masked]>
Date: Fri, 4 Mar 2011 18:35:27 +0000

If I understand correctly, the question of what capabilities are presented is different than the question of mandating a mixer's use of the available capabilities. I don't think we need a specific use case for the latter, and tend to agree that doing so may push the limits of CLUE's work.

On the other hand, we do need to consider the kinds of dynamic behavior that can occur as endpoints offer new capabilities, rich endpoints come and go, etc. So the point of the additional use case would be simply to make sure we cover a (perhaps degenerate) case of multistream endpoints in which only one is a physical site. 

I agree that a user connected to a conference mixer is a call between two endpoints. But isn't that true of any multipoint call? So we want to make sure to cover enough cases so that the CLUE stuff is complete.

Jim

-----Original Message-----
From: Charles Eckel (eckelcu) [mailto:[email-masked]] 
Sent: Friday, March 04, 2011 9:30 AM
To: Peter Musgrave; Cole, Jim (HP Visual Collaboration R&D)
Cc: [email-masked]
Subject: RE: [clue] CLUE use cases comment

I think there is not a need to model this separately. I regular endpoint may do the same thing. For example, perhaps I initially make an audio only call. Later I choose to enable my video capabilities. Then at some point I add presentation. Of course I could have offered all of these capabilities from the start, but that should not be mandatory.

Cheers,
Charles

Of Peter Musgrave