RE: Moving forward with VCAT/LCAS...

["Stephen Shew" <sdshew@nortel.com>]

Alex, I assume that the "one step" case below is simply an optimization
of the "loose coupling + policy" approach.  That is, the policy is to
teardown the server when the client no longer needs it.  I think it
would be a mistake to define this behaviour in a protocol without the
ability to control whether the server layer is torn down when its
association with the client layer is removed.

Stephen

-----Original Message-----
From: owner-ccamp@ops.ietf.org [mailto:owner-ccamp@ops.ietf.org] On
Behalf Of Alex Conta
Sent: January 14, 2008 14:47
To: ccamp@ops.ietf.org
Subject: RE: Moving forward with VCAT/LCAS...

Greg,
 
From the perspective of the "users" of a VCG - applications or clients
of the VCG  which are the layers above the VCG (above both VCG client
and server). -  the awareness, the information about the VCG members,
and furthermore, their presence before, or after VCG creation or tear
down, does not really seem relevant, or directly useful. 
 
From a "management/provisioning" perspective, setting up the components,
independently from the client layer - as a first setup step - and then
converting/transforming these elements into VCG members, once a VCG
group (and client) has been set up - as a second setup step - and then
at tear down, after VCGs tear down, keeping the server elements around,
seem to be reducing the number of subsequent setup operations, if those
elements can be and are reused with subsequent newly created VCGs.
 
It can be argued though, that in a case - a VCG application - in which
existing server elements CANNOT  be reused, a one step creation or
tearing down of VCGs - in which client and server elements are
created/setup, or torn down together, instead of a two step, and keeping
server layer elements around - is more appropriate. 
 
So the preferred "default" behavior may depend on the type of VCG
applications, and could be best left as a choice for the system
developer to make. 
 
Regards,
Alex Conta
 

-----Original Message-----
From: Greg Bernstein [mailto:gregb@grotto-networking.com]
Sent: Friday, January 11, 2008 11:03 AM
To: Alex Conta
Subject: Re: Moving forward with VCAT/LCAS...


Nice analysis/summary Alex.  I like the "looser coupling" + policy
(default behavior) approach that you put forward.
Let me know if you've got solution preferences (on or off the list).

Regards

Greg B.
<snip>