Benefits of a 3-tier Architecture
The eSCL system is based on the Application
Layer of a 3-tier architecture.
This has several advantages:
-
Clear separation of user interface
control and data presentation from application logic
-
Centralized data storage, easy to manage
-
Scalable, load balancing
-
Change management: simpler and faster
to exchange a component on the server side
The eSCL Package
The eSCL package is composed of several
components which are used to develop business rules as well as the frameworks
for execution of business rules.
-
a business rules development environment
- this is used to develop portable business rules using our HyperScripting
language. Rules developed for one platform will run on another (NT
vs. Solaris or Linux). The development environment allows a user
to add, delete, or modify logic to evolve features of a system easily in
a straightforward manner. This tool is used offline, to prepare business
rules for real-time execution.
-
a rule execution engine - this is the
real-time execution component of the eSCL system. Business Rules
are triggered based on event and are executed in real-time by this engine.
This component can be fielded on servers as well as client side applications.
The rule execution engine has a minimal memory footprint and is designed
for efficiency in real-time environments.
-
Message Broker
- an Interprocess Communication (IPC) Software Bus. This SOAP-like
product passes XML messages between applications. Its strengths are
in its simplicity and ease of use. The Message Broker is an excellent
tool to allow eSCL to integrate legacy applications or add gateways and
custom applications under control of the eSCL expert system.
-
Event Queues
- an asynchronous queuing mechanism used to send events to the Expert System.
The Event Queues are used to forward events onto the eSCL system(s).
The Event Queues are built on a robust, scalable technology which supports
load balancing (multiple CPUs running eSCL), message persistence and replication.
-
Messaging Bridge
- an application can notify users of events or pertinent data using devices
services by an e-mail technology. Pagers, cell phones, PDAs, and
standard desktop e-mail clients can be notified from the eSCL system.
-
Schema Examples - to get started with
eSCL, the user will need to implement a minimal schema to define events
and user profile information. These samples will provide a quick
start for a new project.
-
Extended Stored Procedure and Trigger Samples
- these samples will also aid a developer to set up triggering mechanisms
to notify the eSCL expert System and give an example of the message formatting
and how to call the Event Queue with the event record.
-
.DLL and eSCL API - .DLLs or Libraries will be
provided with all bridge code between the Database tools and eSCL. All
APIs for the eSCL system are documented and included as part of the Source
Alliance
system.
Additionally, eSCL developers may wish to
use additional development tools we offer.
-
Visual Scripting
- a drag-and-drop GUI used to graphically define logic for Business Rules.
This is a plug-in for Visio which allows a user to perform "flow chart
programming" and have eSCL scripts and rules generated automatically.
-
Web GUI Builder
- for developers of wireless applications, presenting the same information
to a PDA, Cell Phone and a standard monitor can be a sizable task.
This tool allows the deployment of the same look and feel across platforms.
