Subject: RE: [XCON] DP4.2: Defining new templates

From: "Mary Barnes" <[email-masked]>
Date: Fri, 27 Jan 2006 12:18:29 -0600

In re-reviewing this thread (to which no one has responded thus far on
the list), I think Brian is arguing for simplicity - i.e., do we really
need this flexibility in dynamic controls?.   

My personal viewpoint, is that given where we are in trying to complete
this work, that simplicity would be a good objective, unless someone has
a compelling reason why that's not at all acceptable.  Initially, I was
considering it advantageous for the framework to be extremely flexible,
but it seems that allowing too much flexibility is leading to confusion
over the basic functionality provided by the framework.  

So, I'm proposing to modify the proposed change below and include the
following text at the end of the last paragraph in section 5.2:

"The addition of new elements or the modification of the controls within
an element of an
existing template requires the definition of a new template."

Note, that the last paragraph of section 5.2 discusses the concept of an
abstract user interface definition and I think that's still okay:
"  A conference template can also include an abstract user interface
   definition in terms of sliders, radio boxes, etc. for simplifying
   user interaction with a specific non-trivial feature. "

If folks don't agree, please respond and propose alternative text.

Thanks,
Mary

-----Original Message-----
From: Brian Rosen [mailto:[email-masked]] 
Sent: Wednesday, December 28, 2005 9:30 AM
To: Barnes, Mary [RICH2:B601:EXCH]; [email-masked]
Subject: RE: [XCON] DP4.2: Defining new templates

So, I'm not sure I like this.

Generally, I like some flexibility, so, generally, I hate saying "you
can't".

OTOH, we are talking about something that is primarily a user interface,
about which I have a reasonable amount of experience.  From that
experience,
I can say that a well designed client would NOT APPRECIATE hearing from
a
server that this particular server happens to have added a few dozen
minor
controls, and would the client please dynamically render them in
addition to
those carefully designed by a quality user interface designer to meet a
specification.

It is NOT a matter of saying, "well no one forces you to use those
controls".  As we all know, the likelihood is that, actually, it won't
really work, in the sense that the user won't have a good experience, if
the
controls aren't rendered.

If you want a good user experience, you don't have variations from
server to
server for a well designed client; they all work the same.  For that
reason,
I think we are best to NOT have this flexibility.

I've gone along with people who want to retain the ability for a client
to
connect to a server, discover that a conference uses a template it
doesn't
understand, and attempts to render a user interface for it.  I think
users
will not like the result, but, hey, there might be a genius out there
who
can make it work.  It doesn't stop a well designed client who implements
the
template from doing its work well.  Allowing a server to dynamically add
controls would.

Brian

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of
Mary
Barnes
Sent: Friday, December 23, 2005 7:12 PM
To: [email-masked]
Subject: [XCON] DP4.2: Defining new templates

One of the points we discussed was:
DP4.2 Whether clients can dynamically use new templates or whether new
templates require new SW in clients?

The current wording in the framework supports the former proposal, 
specifically, section 7.3 currently states:
"A client may need to query any templates in
the blueprints that it doesn't understand and then make a decision on
compatibility."

Part of the confusion here (at least for me) is over what is meant by
"new".  There seemed to be unanimous agreement that a client can query a
template that it doesn't currently have or has not previously used.
That isn't the same thing as saying that templates can be dynamically
created by a conferencing system. Per the framework, all the templates
used by a conferencing system must be documented and registered.  So,
the discussion ended up being more around what could be changed within a
template without requiring SW changes.  After discussion, the group of
authors seemed to agree that while modifications in the form of new
controls added to elements of a template could be done without the need
to register anything or define a new template, but adding new elements
does require appropriate documentation and registration (i.e. a client
can't be expected to understand new elements). 

To clarify this, we could reasonably add something like the following
the 2nd paragraph in section 5.2, which introduces the template concept:

"It should be possible to modify the controls within an element of an
existing template, without defining a new template.  The client can than
attempt to render the modified element to make use of the potential new
functionality.  However, adding new elements does require defining an
entirely new template as discussed in the previous paragraph."

Mary

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