Cloud is the true implementation of Service Orientation. There may be some resistance and reluctance in adopting SOA in the traditional environments. But on the Cloud, there is no choice. The only way one can exploit the benefits of the Cloud is by implementing autonomous and independent components that are loosely coupled through asynchronous messaging. Applications architected based on these principles will deliver the best return on the Cloud investments. Amazon has been advocating this heavily by encouraging developers and architects to consume Simple Queue Service (SQS), Simple Notification Service (SNS), Elastic Load Balancer (ELB) and other related services. Building on the same theme, AWS now offers a robust orchestration engine on the Cloud called Simple Workflow Service (SWF) that will make it easy and affordable to build SOA based solutions. The key benefit of SWF is the integration of On-premise assets with the Cloud services. Without compromising on the security and compliance, enterprises can build complex workflows that span both on-premise line of business applications and the contemporary Cloud applications.
The classic scenario of an eCommerce platform that has a storefront on the web but the inventory, warehouse management, shipping and CRM integrated with an on-premise ERP is a great candidate for SWF. When a customer completes the check out, a workflow gets kicked off which will validate the order, processes the payment, checks inventory, notifies the warehouse staff and finally schedules the shipping. This entire process has multiple actors running on the public domain, behind the firewall of the enterprise and a 3rd party service in the form of logistics/shipping. Achieving this today is very complex, expensive and involves customization of complex software like Microsoft BizTalk Server or IBM WebSphere. With SWF, enterprises can now subscribe to orchestration as a service on a pay-as-you-go model and reduce the cost and complexity.
As @Krish from CloudAve.com pointed out in his article, AWS is quietly investing in the key areas that will position them as the next gen PaaS provider. At the first look at SWF, I realized that it is complete in its form and ready for the real world deployments. It is very hard for the traditional PaaS players to match AWS on this front. The only competitor that I personally think that has the potential to match is Microsoft. Microsoft has at least 3 offerings in this space – 1) BizTalk Server, 2) Workflow Foundation and, 3) Azure Service Composition. @maryjofoley raised doubts on the roadmap of BizTalk in July 2011 and nothing much has changed since then. Azure Service Composition was discussed heavily at PDC 10 but it has made no progress. There is no clear direction on using Workflow Foundation on Azure for the .NET developers. So, integration strategy on Cloud from Microsoft is confusing with no specific guidance.
Integration as a Service is the next killer offering on the Cloud and it is clear that Amazon has got it right!
- Janakiram MSV, Chief Editor, CloudStory.in