My company are about to implement a new architecture in which we have proposed BizTalk (we are a Microsoft shop) as the Enterprise Service Bus (ESB) in a SOA (please don't quote Service Oriented Ambiguity) environment.
Our business is to take Orders through our new Order Capture GUI which must connect to our Customers Database, Product Catalogue, Ordering System and some other ancillary systems each of which will be exposed as WCF services, orders are then passed to our Order Management and other downstream systems for fulfilment and finally to our Billing system for invoicing. Currently each system has its own GUI and uses manual process to pass information between them, in an effort to automate and integrate the natural thought was to introduce an ESB to connect them.
Some of my rationale for an ESB is, the bus will worry about how to connect the systems (each system is agnostic and knows nothing of any other system) and how to format/translate the information. It is highly likely that in the future some of the existing systems will be swapped out for new systems or systems within our family of companies.
This seems to make sense to me but I am now being met with some resistance as to why introduce it when a Point-to-Point solution could suffice.
Unfortunately in the company history (prior to my appointment) an initial attempt to introduce BizTalk failed, but I am confident that it has a place and I can deliver it.
My question is perhaps not so much about BizTalk but whether an ESB is a good idea in my scenario described, when does it make sense to introduce an ESB?
Best Answer
Okay. ESB Guidance on Biztalk from the presrciptive architechture group - http://msdn.microsoft.com/en-us/library/cc487894.aspx
We use BizTalk where I work to do a lot of things. He have some simple point intgerations. We have some more complicated point integrations with hihgly customized adpaters and pipelines. We have divisional enterprise system integrations for customer master, product info and price and quote to order. These are all seperate BizTalk applications. Some quite small and some quite large. We mainly have used BizTalk to do point to point/many point slutions without using an ESB pattern. The implementation of an ESB implies a level of governance of the bus itself and the enterpise message standars that will be permitted on the bus. If you will be interfacing with a large number of systems with a large number of different formats - ESB makes a lot of sense. If the integrations you want to achieve are less ambitious, an ESB may be overkill. That being said, it's a clean and extensible architechture. You'll have to make the cost value decision.
BizTalk is also a complicated beast but with allof the moving parts comes a level of flexibility that is wonderful. But be prepared for a learning curve or some consultant costs.