# Presentation: 354154

## A Service OrientedLive Access Server

- Roland Schweitzer
- Steve Hankin
- Kevin O’Brien

- Jonathan Callahan
- Ansley Manke
- Steve Du
- Jing Li

## Highlights

- Introduction to LAS
- Partnerships
- Goals for redesign
- Introduction to new LAS
- Product Server
- Backend Services
- User Interface
- Summary

## The Live Access Server (LAS)

- A highly configurable Web server designed to provide flexible access to geo-referenced scientific data

## Information hierarchy:NVODS LASorganized by institution...

- Information hierarchy:NVODS LASorganized by institution...
- NVODS is also organized by scientific discipline, data source, time resolution, and data set name.

**Notes:**
Showing snapshots of the NVODS LAS interface by way of illustration ...
Bi-directional integration – other datasets into OSMC, OSMC into NVODS ...

## Applications of LAS – Office of Climate Observations Observing System Monitoring Center

## Applications of LAS - NOAA’s Office of Climate Observations Adopt-a-Drifter

## Earth Systems Grid

- 9 partners including LLNL and NCAR.
- 5-year proposal
- Redesigned architecture to be discussed today will be the starting point for the integration of LAS into ESG.

## Current LAS

- Mouse Clicks
- Typing

- Product Server

- User Interface Server

- HTML Page:
-    Data selection
-    Region selection
-    Data constraints

- HTML Page:
-    Product Output

- Database Access

- Legacy Application

- Configuration Information:
-    Data Sets
-       Variables
-    Operations
-       Options
-    Services
-    Properties
-       Data Set
-       Variable
-        Operation
-        Arbitrary User Defined

## Goal

- Separate the generation of output products from the core software to make it easier to create new products
- Better performance
- Keep more information in memory
- Make it easier to specify behavior of components with name/value properties
- Easier to integrate with standards, existing software tools (e.g. UniData netCDF Java code)
- Easier to install

## Redesigned Product Server

- Product Server

- XML Product Request via HTTP GET

- Backend Service 1

- Backend Service 2

- Backend Service 3

- Backend Service 4

- Byte Stream

- Data Access URL

- HTML Page:
-    Product Output
-    Progress
-    Error
-    Cancel

- Configuration Information:
-    Data Sets
-       Variables
-    Operations
-       Options
-    Services
-    Properties
-       Data Set
-       Variable
-        Operation
-        Arbitrary User Defined

- HTTP Request/Response

- SOAP over HTTP

- Unspecified

- New protocols (SOAP, etc...)

## Product Server

- Brokers requests between requesting client and services need to fulfill the request
- Products delivered to user in multiple forms
- HMTL page
- XML document
- Raw bytes of images and text
- Chained operations using one or more services
- Generalized method to communicate properties to backend service

## New Backend Service

- Backend Service

- Backend Response XML

- Backend Request XML

- Database Access

- SOAP over HTTP

- Unspecified

- netCDF File

## Backend Services

- Create products on behalf of the product server
- Backend services are formal Web-services
- Multiple backend services for one LAS request
- Services implement only one method that takes in a backend request XML string and responds with a backend response XML string.

## New Backend Service

- Backend Service

- Backend Response XML

- Backend Request XML

- Run Ferret

- SOAP over HTTP

- Unspecified

- GIF plot file

## New Backend Service

- Backend Service

- Backend Response XML

- Backend Request XML

- Unknown Activity

- SOAP over HTTP

- Unspecified

- Unknown Result

- (OGC, WMS, WCS, etc.)

## User Interface Server

- Interacts with configuration information to guide user in selection data sets, variables geographic regions, time intervals and products

## User Interface Server

- HTML Page:
-    Data selection
-    Region selection
-    Data constraints

- Mouse Clicks
- Typing

- Product Server

- HTTP Request/Response

- HTML Page:
-    Product Output
-    Progress
-    Error
-    Cancel

- Configuration Information:
-    Data Sets
-       Variables
-    Operations
-       Options
-    Services
-    Properties
-       Data Set
-       Variable
-        Operation
-        Arbitrary User Defined

## Redesigned User Interface

- Lots of changes “under the hood”
- All configuration information kept as singleton objects in memory shared by all sessions
- More transformations of configuration information to interface widgets done “on-the-fly” for flexibility
- Many (all) products can be “interactive”
- On-the-fly addition of constraint widgets based on data from the product server

## Redesigned User Interface

- Interlocking menus control slice through the data, which in turn controls the operations.

- Widgets control slice through the data, which in turn controls the operations.

## The Live Access Server (LAS)

- A highly configurable Web server designed to provide flexible access to geo-referenced scientific data...
- ... which is being redesigned and improved with a phased release of new features
- Old user interface with new product server and backend services this summer
- New user interface with new product server and backend services some time later.