I have a requirement to build one parent site and few child sites..using domain and sub-domain concept and want to have installations of joomla at parent and all sub-domains. But I want only my parent site to hold user data and Alpha user points data while my child sites would be hosting components and modules separately and use user data and Alpha user points data from parent site.

Could any one suggest me is it a good Architecture to go and is there any extension or component already available to achieve it. Example
below:

parent site movies.com Child sites braveheart.movies.com, troy.movies.com

I will have forums, blogs and other component installations at braveheart and troy sub-domains seperately while my Alpha user points and users db/tables would reside at movies.com(main domain).

It's like single-sign on or Centralised Alhpa user points, but free to install same component and modules at different sub-domains.

Highly appreciate any replies or solutions proposed

The concept of JMS is based on the sharing.
- Sharing of the same joomla application (php code)
- Sharing of the content of a limited number of extensions.
See the list of extension currently defined in the JMS tool and also the one
that can be shared depending on the Joomla version.
(Remark: The column Share 3.2 is also applicable for J3.3)
www.jms2win.com/en/list-of-extensions?vi...id=269&Itemid=53

Based on your description, I understand that you want to have a parent
website and several subdomains (child sites) that share the content of the
"Alpha User Point" extension.
This is possible to share the Alpha User Point.

In terms of architecture, if you follow our recommendation presented in
several Joomla day power point
ie.
www.jms2win.com/en/documentation/doc_det...-day-strasbourg-2012
we suggest to have:
- Master website that just contain the extension (no data) ie.
master.movies.com
- Portail or parent website (www.movies.com)
+ - Your child website under the parent (child.movies.com)


You can already do that with the JMS basic edition.
The Single Sign-In is theorically not required when using subdomain (except
if you have sohusin or special stuff to forbid apache to share the session
info).

You can only install in a slave site an extension that is already present in
the master.
Remember that you share the PHP code in the master.
The slave site USE the php code that is present in the master.
So you can NOT install something in a slave site that does not exists in the
master.