Re: [Vrs-development] Jump-start / status check

[Chris Smith]

On Sunday 06 October 2002 08:40, Eric Altendorf wrote:

> OK, here's my initial try.  In one sentence, "the services manager is
> the module that coordinates the reception of service requests and
> their actual fulfillment by the web services (aka EDO's)."
>
> In short, at a very high/abstract level, I see the SM doing the
> following:
>
> * listening for EDO service requests
> * checking to see if the requested service is "enabled"
>   (allowed to be run) on that node

Yep.  Mostly they will.

> * If it's enabled, the EDO for that service is loaded
>   from the RM (if it's not already loaded), and then executed,
>   the results being returned to the client

Whether the 'cache' layer is a property of the RM or a property of the SM is 
still under discussion.  There are pros and cons for each.  
Add that discussion topic to your SM list!

> * If it's not enabled, the SM checks with the cluster manager
>   to locate another node which supports the required service,
>   and forwards the request to that node.

This is an interesting problem.  Idealy you want to re-direct the requestor 
to the node that can satisfy the request - however, the VRS will support 
multiple protocols (XML, Jabber etc) so this can only be done if it is 
supported by the protocol.  Thus we may want to support two mechanisms - one 
where the client is redirected (far more efficient) and one where we route 
the request internally (more network hops).


Chris
-- 
Chris Smith
  Technical Architect - netFluid Technology Ltd.
  "Internet Technologies, Distributed Systems and Tuxedo Consultancy"
  E: address@hidden  W: http://www.nfluid.co.uk