[Pipet Users] Update

[Nicolas Chauvat]

> The main task of the BL is communications between instances of Piper.
> Emerging tasks are resource management and security.
> 
> Some issues that come to mind atm are:
> 1. Resource localisation (a central registration server that keeps
> track of Piper instances)
> 2. Offered data streaming (push)
> 3. Requested data streaming (pull)
> 
> Other stuff we'll need, and that's outside the scope of kqml, are
> 4. Node relocation (numero uno pain in the butt)
> 5. Authentication (probably Akenti, but maybe Sesame)
> 6. Resouce management (like ram, HD space, ea)

Ok, let me rephrase that: You want the BL to manage both the process
distribution aspects and the node coordination aspects.

* 1, 2 and 3 are directory services (who does what and where)
* 4 and 5 belongs to the node coordination topic
* I'm still not clear what 6 is.

Two more question:
* are you sure you want 4 and how good do you want it?
* are you sure you want to use a centralized approach for 1?

The main comment I have is that this looks like we need to do some reading
and look at distributed architectures, for the above subjects have been
worked on already. I can't suggest a solution as I don't know what kind of
information the directory srevices would have to publish and query, nor
what 4 and 6 precisely are.

> Ic. This is bad indead. darn.. really bad. Maybe that's why all the
> code I could find was made 5-6 years ago.

Depending on what you actually need, you may get away with something like
RPC-over-something-else. Ever thought of SOAP maybe? Narval is using the
python implementation by pythonware.com. Slow, but standard.

-- 
Nicolas Chauvat

http://www.logilab.com - "Mais où est donc Ornicar ?" - LOGILAB, Paris (France)