There's an important discussion under way among cloud computing's inner circle on the subject of interoperability. Service providers and implementers recognize that adoption will be hampered if they don't come up with a good way of integrating data and applications across clouds.It's a new debate on a familiar problem, that of cross-platform interoperability when multiple vendors are racing into a new market. The recently formed Cloud Computing Interoperability Forum (CCIF) has become the nexus for much of the discussion. You can find a mission statement, discussion threads, and contact information for the group's members here. Cisco, IBM, and Sun are among the early participants.

Cloud players, including some of those involved with the CCIF, met yesterday at TechWeb's Cloud Connect event in Mountain View, Calif. There's a Twitter thread (#cloudinterop) on what transpired at the get-together. It's clear that the industry is still brainstorming over possible approaches.

Reuven Cohen, CEO of cloud vendor Enomaly and an active member of the CCIF, has ruminated on the topic in several blog posts. "When thinking about what cloud interoperability truly means, for me it's all about the API," Cohen wrote yesterday. "What seems to have happened over the last year is what I call cloud API propagation. Every new cloud service provider put their own spin on how a user or cloud application interacts with 'their cloud.'"

There are a number of ways to deal with the proliferation of cloud APIs. Cohen proposes a "unified cloud interface," or cloud broker, that implements industry standard definitions. Dave Powers, an IT pro with Eli Lilly, talks of a third-party "orchestration layer" as a way of managing multiple cloud services. See my post "Eli Lilly On What's Next In Cloud Computing."

It's too early to know how all this will play out, but IT folks should be paying attention and, if cloud computing is part of your company's strategic direction, looking to get involved. The CCIF meets again in New York in March.

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