OpenLink
Software's Multi-Tier ODBC Driver Architecture
Open Database Connectivity Without
Compromise !
Various OpenLink Database Agents
OpenLink ODBC (MT) Drivers are based on a concept of in-process Objects (a concept employed by emerging Objects Technologies, such as OLE 2.0, DSOM etc..). OpenLink ODBC (MT) Drivers are made up of four key component Objects ;-
- Generic ODBC Driver
- OpenLink Request Agent
- OpenLink Request Broker
- OpenLink Database Agents
OpenLink Component Objects are abstractions of all the key technologies that make up the Client-Server, Distributed Processing, and Co-operative Processing, Computing models.
All of the Objects that make up an OpenLink ODBC (MT) Driver, adhere to established, recognized standards or De facto standards.
The Generic ODBC Driver
This is the upper most abstraction layer within the OpenLink Multi-Tier architecture, it is a database independent implementation of the Microsoft ODBC 3.x specification, conforming to the following levels within the specification: Core, Level 1, Level 2, and Extensions.
ODBC compliant applications establish session with our Generic ODBC Driver via the ODBC Driver Manager.
The OpenLink Request Agent
The next layer within our OpenLink Multi Tier Driver's Architectures, is an in-process Object called the "OpenLink Request Agent". The Request Agent's main responsibilities, are to provide the following services to the Generic OpenLink ODBC Driver ;-
- Database Session Establishment - via the OpenLink Request Broker.
- Message Relaying - between the Generic OpenLink ODBC (MT) Driver and one or more OpenLink Database Agents.
This in process object is responsible for spawning or replicating one or more OpenLink Database Agents, and then associating these Database Agents with the OpenLink Request Agent.
The OpenLink Request Broker applies a "Rule Book" approach to the process of spawning, replicating, and associating Database Agents with the OpenLink Request Agent. This unique feature enables centralized, flexible and Multi dimensional management, of your OpenLink ODBC based Client-Server infrastructure.
OpenLink Database Agents
These in-process objects are the only components within the OpenLink ODBC Multi Tier Architecture that are database specific. The architecture of all OpenLink Database Agents are exactly the same, it is only the methods that make up standard OpenLink Database Operations that is database specific.
The Database Agents act as data access servers for the OpenLink Request Agent on one hand, while on the other hand they act as Clients to the database server processes, of the relevant databases that they support.
The OpenLink Database Agents Architecture is high level abstractions of the SQL Access Call Level Interfaces (CLI) Spec. Thus, OpenLink Database Agents are built using the relevant Database Engines Call Level Interface. OpenLink Database Agents are available for the following databases engines : Oracle 6 & 7, Informix, Progress, Sybase, Ingres, Unify 2000, MS SQL Server, and SQLBase.
Table Of Contents | Next | Previous
