Enterprises of all sizes need an integration strategy. This strategy allows the organization's disparate applications, both on-premise and in-the-cloud, to smoothly run their businesses. Today there are numerous choices available for an Enterprise Service Bus (ESB). I would put these offerings in one of four categories:
1. Licensed ESB
2. Integration Appliance
3. Open-Source ESB
4. Integration-as-a-Service (IaaS)
The established players are the Licensed ESBs from companies such as webMethods and Tibco (among others). Integration appliances such as those from Castiron have had success in recent years. The Open-Source movement has produced the Mule ESB. The new kid on the block is Integration-as-a-Service. Boomi is the IaaS vendor that has received the most press recently. I have blogged recently that IaaS is a technology whose time may finally have arrived, after numerous attempts at this in the past have failed.
Each of these integration strategies has its benefits and drawbacks. Licensed ESBs tend to require significant capital but are the most robust of the options and have the largest communities. An Integration Appliance, while somewhat less expensive than licensed ESBs, also are capital intensive. They also aren't as well established and thus have smaller communities. Open-source ESB (such as Mule) are becoming a better low-cost option as the communities around them have grown in recent years. As with all open-source software, the organization must have a significant depth of technology talent to ensure its success.
The new kid on the block is Integration-as-a-Service. As an integration strategy, IaaS has its appeal. This appeal stems from the benefits of any cloud-computing service: No servers/hardware, no data center, no system administrators, no software version upgrade cycles. These benefits are driving the adoption of cloud-computing across other segments and now those benefits can be realized with Integration as well.
The pricing model for IaaS is quite different from the other integration strategies. Customers usually pay by connection, the type of connection, and by transaction volume (including message size). This model isn't right for every organization. If most of your applications are on-premise (behind the firewall), IaaS may not be right for you. Single-points-of-failure when integrating with on-premise apps may also be a concern, although this will likely be addressed over time. But if the apps and services that your organization use are primarily "On The Cloud", (and more and more organizations are following this strategy) IaaS may be right for you.
