An architecture for remote processing
Transcript An architecture for remote processing
Remote Visualisation System
By: Anil Chandra
Obtain image data residing on different machines at
Visualise the images – whole images or subsets of larger
Ability to interact with (analyse) visual data
Allow overlaying of catalogue information
Provide services at a satisfactory speed
Current Model 1
1. User requests an image/data from a particular service.
2. User receives a rendered raster image (e.g. gif) or
3. User visualises downloaded image on local computer.
Current Models (cont)
The current model is an example of client side
- All processing is done on the client (user’s
What is RVS?
A distributed software system that allows scientists to
view and analyse astronomical data that are stored in
A server-side visualisation system
Image + metadata
Raw image data
Client User Interface
Web browser or standalone application
Most processing occurs on the RVS server, not on
the client computer.
Obtains and stores images from
Processes images based on user commands
Uses AIPS++ Display Library (but not restricted to)
Provides its service via SOAP
RVS Server Design
Distributed architecture (via CORBA)
Data Centre Manager
Client – Server Communication
SOAP Interface to clients
Standard and popular protocol for web services
Allows custom clients
Based on XML, so it’s programming language and platform
Why Server-Side Visualisation?
More processing power on servers than on the average
Servers can hold larger images than the average PC due
to more memory and storage space
Servers can receive larger images faster via higher
bandwidth connections to data centres
Any time, any where access
Server-Side Visualisation (cont)
Software maintenance/upgrades transparent to users
Only the server needs to be upgraded, not all the clients.
Existing tools such as AIPS++ can be utilised (no need to
install on clients)
Supports concurrent users access to same session
Disadvantages of Server-Side
Difficult to design/implement
Poorer performance with smaller size data that require
High reliance on server availability/integrity.
The VO Context
RVS is a visualisation tool amongst the many tools in the VO.
RVS may be used:
By end users to view and analyse images
In conjunction with other services (such as data mining)
By data centres to provide a visualisation interface to their data
It’s based on a more generic framework that may be used bring
other services, besides visualisation, online.
High Level Design complete
A simple prototype (proof of concept) is in progress.
To be completed by 28 Nov 03
Project completion date: 25 May 04
A complete RVS Server
A demonstration client