[Sigia-l] Notes: Multi-agent system configuration(policy issuing)

[Yilin Qiu]

Dear Information architects,

I'm working on an online community info system 
and the following is from my architecting notes:

The dynamic nature of information system requires 
the system behaviors be altered by a network of
participants (users or other systems), in various
aspects, scopes and levels. Among all the runtime
inputs, those affect the system's behavior at
rule/logic level constitute the dynamic part of 
system configuration.

Aspects of Multi-Agent System Configuration

(1) DataType  An OOP type is a result of the
classification of objects in a system by behavior 
and data structure. In general OOP, the static
correspondence between type and Class implementation
will become optional: types need to be modified at
runtime. This is achieved by dynamic typing at
object model level (DTM): where a type is an object 
of a special class which holds the runtime manageable
data that regulate the objects of the type. DTM
makes Type Data Management the most important part 
of Configuration

(2) Privileger  Some privileged objects (type, owner
etc) may have various levels of configuration controls
over an object. Such controls form a directional
graph.

(3) Instance configuration  An object might have its
own additional behavior settings beside those from 
its type.

(4) Meta Configuration  Both type and instance 
configuration need to follow some rules which conform
system's ultimate purpose. Such rules plus a set of
fixed logics form the Meta configuration.

(5) System Configuration    There are no needs to 
discuss system configuration separately if system
itself is typed.

(6) The Configuration Issuers  The capability of
providing the right tools and right scope of data
access per system access is called the service
localization with respect to participation (SLP). 
SLP is itself the result of configuration. Handling
multiple configuration (possibly concurrent)updates
from agents (issuers) is interesting and challenging;
more importantly, it's demanded by every real
operational situation.

(7) The Runtime Configuration This is the runtime
merging result of (possibly partial) configurations 
by various issuers.

(8) The Transition of Configuration  
Similar to the real operational world, certain 
configuration transition policies are needed
and should be part of Meta configuration.

Multi-Agent System Configuration architecture

 (1) Configuration Data Structure    
Property list is proposed to be the data structure of
configuration. Its formal recursion capability is used
to present the hierarchical nature of configuration
data.

  (2)The Uniqueness of Configuration KeyPath.   
Meta configuration shall determine the keyPath of a
set of configuration data per theme. Any objects
hold configuration data of a theme shall find the 
data by the keyPath uniquely determined by theme and
reference data type. Any configuration is a data
subtree of the configuration tree defined in the Meta
configuration tree structure wise; and the merging
logic is readily found in the Meta configuration by
the uniqueness of the keyPath.

  (3)The Merging Algorithm   
There is a default merging order which can be
overridden by Mata configuration and the real merge
procedure is recursive until the leaf merge (data 
item merge).

  (4)The Transition of Configuration  
Some study results of dynamic configuration
performance and the possibility of configuration
caching were obtained: dynamic configuration adds
very little performance overhead and architecture
is generic enough for information systems of various
kinds. 

comments and questions are very welcome.
Thanks.



		
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