Business Integration Services
Business Integration connects systems and applications to each other using mutually agreed-upon messages and routing schemes. Enterprise Messaging systems let programs communicate by exchanging messages, much as people communicate by exchanging email. Unlike email, enterprise messaging systems provide guaranteed delivery, speed, security, and freedom from spam. Until recently, there was no open standard for Enterprise Messaging systems, so programmers either wrote their own, or used expensive proprietary systems.
Now there is a standard. Catenary Software uses an Open Source protocol from Apache. AMQP Advanced Message Queuing Protocol is the first open standard for Enterprise Messaging. It is designed to support messaging for just about any distributed or business application.
Example 1: Address Change
Consider a corporation with four departments: Sales, Accounting, Manufacturing and Corporate. Each department already has its own suite of applications and databases. None of those systems were designed to talk to each other. Sales learns an important client is moving its headquarters to a different city and its warehouse to yet another city. How will the other departments know to update their own databases with the new bill-to and ship-to addresses?
If that address change could be published and all the other systems could subscribe to changes of that sort, each system can manage the address update on its own terms.
Example 2: Order Taking
Your customers order products through your website. Others use EDI to place orders. Your firm's sales staff uses an internal ordering system to book orders over the phone. How can your firm's internal order fulfillment software manage all three gateways, sending appropriate acknowledgements back through each pipeline?
If each gateway reads in the order and publishes a common message to a single queue, the ordering system would have a single point of entry. The order processing software consumes the order and publishes to a single outbound order response queue. Each gateway subscribes to the order response queue, consumes its responses and formats each response appropriately.
Example 3: Upgrades and Replacements
Your order processing software requires an upgrade. Using the previous example, how can your firm avoiding impacting other systems dependent upon it? The upgraded system can read from the same queue as the old system if you're using an Enterprise Messaging System.
Summary
Numerous other advantages arise from a properly architected Enterprise Messaging System. Like email, if a subscriber is offline, messages can stack up in persistent queues until the subscriber comes back to consume them. Enterprise Messaging Systems can be made fully redundant. The first two examples are trivial but the third is not. They illustrate the need for Business Integration in a world of square pegs and round holes, where systems must cope with the world where there's no push-back.