Tata Communications plans to use  Cloud.com‘s CloudStack — an open source platform — as the foundation for Tata’s InstaCompute public cloud offering. This isn’t a small deal: India-based Tata Communications generates US$2.39 billion in annual revenues. And now Tata is partnering with Cloud.com to bring SaaS to small and midsize business customers.

Tata’s solution strives to deliver secure, elastic compute and storage as a service to enterprises that might not have the IT resources on their own. In the same press release, Tata praises the reliability, scalability and flexibility of Cloud.com’s IaaS platform.

Cloud.com describes InstaCompute as one of the biggest cloud rollouts on the planet. If true, it could an intriguing momentum-booster for a company that’s come out swinging in 2011.

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