Frank Kenney from Gartner coined the term "Multi-Domain Registry/Repository", or MDRR, in a tweet recently.

What is an MDRR and why is it important? To understand, think of a registry/repository traditionally seen as part of a SOA architecture. It is supposed to include addresses of the services available in the SOA, plus metadata about the services, such as their policies.

Now think about how organizations are starting to rely on Cloud-based services, such as Amazon S3 (storage) and Force.com (sales force automation). These services are not on-premises SOA service, so they are not in the SOA registry/repository. But the organization relies on these services! This means that the registry/repository does not contain a full compliment of the services which are used by an organization.

But wait, you may say, a SOA registry/repository is intended to manage and control services, and you can't control services provided by Amazon or Force.com because they are simply not under your control. This is true, but the goal is not to control the services. The goal is to monitor the performance, availability, and compliance of these external services. Virtual Services are the key to this. Rather than managing the third-party services, you are managing virtual interfaces to those services. The virtual service is provided by a Cloud Gateway which acts as a broker to the services.

These virtual services are included in a Multi-Domain Registry/Repository alongside internal on-premises services (that's why it's "multi-domain"). From an organization's standpoint, all of the services they depend on are in one place. That's valuable.

Governance services, such as services to scrub data of private information, provided by the Cloud Gateway, are also housed in the MDRR. These governance services are another example of on-premises services. This means that a full compliment of services are present. They are shown in the diagram below:


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Look for the MDRR meme to grow in the months ahead....

And I can't resist the cheesy Hart-to-Hart reference:

On-premises services and virtual services When they met, it was MDRR

Read the original blog entry...