This is my first contribution to the Lotus Notes and Domino Blogging Community Show’n Tell Thursday series. I will give a high-level introduction to architectural patterns using Patterns for e-business as the specific example of architectural patterns and introduce how Patterns for e-business can be used for Lotus Domino applications.

What are Patterns for e-business?: Patterns for e-business are specific architectural patterns and not design patterns (that can be transformed directly into code such as fundamental, creational, structural, behavioral, and concurrency patterns). From the Patterns for e-business site: “Patterns for e-business are a group of reusable assets that can help speed the process of developing Web-based applications” and “customer requirements are quickly translated through the different levels of Patterns assets to identify a final solution design and product mapping appropriate for the application being developed.”

The Patterns for e-business site also describes the process to follow to arrive at a specific architectural pattern for a specific business problem: “For simpler implementations, the Patterns Web site is designed to navigate you through a logical, step by step process to arrive at a previously tested solution design appropriate for use in your e-business application deployment. The steps involved in this process are as follows:

1. Select a Business pattern to meet the needs of the application you’re developing.
2. Select an Application pattern that can implement the application’s specific functionality.
3. Review Runtime patterns and select a pattern that satisfies the system requirements of the solution.
4. Review Product mappings to determine which products have been successfully used for the Runtime pattern selected in step 3.
5. Review Guidelines and related links for the Application pattern and product mapping you selected in steps 2 and 4.“

Patterns for e-business are generic architectural patterns for e-business implementations and can be used with any type of application servers and middleware – not just IBM products. As it is stated: “Note also that, where IBM products are listed as part of pattern implementations, IBM products are not the only solution option.”

The pattern implementations include Self-Service and Collaboration patterns implementations using Domino and Websphere which makes this interesting for Domino developers, architects and administrators. The specific Domino and Websphere product mappings shows how to implement the different patterns such as putting a load balancer and a caching proxy (reverse proxy) in front of several back end Domino servers but also how to combine Lotus Domino with Websphere, Sametime, external directory servers and relational database servers.

Several redbooks and other resources exist on the subject of Patterns for e-business.