MIDAS Architecture

MIDAS
 


The MIDAS middleware components facilitate profile encoding, manage user contexts, identify proper discovery scopes, and provide personalized service views depending on user context.
The MIDAS layered architecture is here depicted.

 
Architecture
 

MIDAS Lower Level Facilities

 

The lower layer provides core facilities for service naming and registration.

In particular, in MIDAS:

  • services are identified with Uniform Resource Identifiers
  • services can follow both announcement-based and pull-based approaches to advertise their availability
  • services can advertise their profiles either to a distributed directory or directly to interested parties in response to client requests.


 

MIDAS Upper Level Facilities

 

The MIDAS upper layer includes the specific facilities for context-aware semantic discovery.

In particular:

  • The Metadata Manager provides graphic tools for the specification, modification, checking for correctness, parsing, and installation of user/device/service profiles.

  • The Context Manager is responsible for creating user contexts when MIDAS users initiate their discovery sessions, for monitoring changes in both created user contexts and in relevant external environment conditions, for notifying changes to interested entities, and for updating user contexts accordingly.

  • The Discovery Manager is the key facility in charge of context-aware semantic service retrieval. DM is composed of several sub-components, each one supporting a specific discovery task:

    • Semantic Matching Engine - supports semantic matchmaking.

    • Discovery Scope Manager - determines an initial discovery scope when a user starts her discovery session.

    • Service View Manager - creates service views at the beginning of discovery sessions and updates them automatically when relevant user context changes occur.

    • Query Processor Manager - processes explicit user queries.



Last updated 01-02-2006