Of course you can build it from scratch or by combining best-of-breed components, but that will not be the most cost effective approach for enterprises that need flexible and productive (from the perspective of the developer) integration tools.
The better options are:
1. Buy packaged integration software like an ESB or a comprehensive integration suite (CIS). This option offers a faster ROI than the build approach and doesn't require deep technical support to use effectively. The downside is you have a capital expense for the software.
2. You can "rent" integration software from hosted providers. This provides the fastest implementation as hardware and software are already installed and there is not capital expense involved. The downside is that larger firms may end up paying higher subscription fees over time than they would pay in software licenses.
3. Depending on your organization's strategy, open source ESB's may be an option. Again, there is no capital expense, but you will need deeper technical skills to work effectively in the open source world. These technical resources may not be available in all areas
For a deeper look into this subject, look at my recent report entitled "Should You Build, Buy, Rent or Download Your Integration Capability?" Also, send me your thoughts on this subject to [email protected]. Thanks!