Stacey Higginbotham, a commentator for GigaOm, recently remarked that a recent HP tutorial on cloud computing was "depressingly similar to the idea of service oriented architecture," noting that "HP offered clouds as merely a means to deliver IT as a service inside the enterprise." (Thanks to Loraine Lawson for the pointer.)
Stacey's point is that cloud computing is more than just something that happens within the walls of the enterprise -- private clouds will certainly be but a small piece of cloud computing. And certainly, the scope of cloud computing extends beyond SOA -- storage provisioning, application rollouts, data management, etc.
SOA certainly has its issues -- and we discuss them here at this blogsite. But from this perspective, I would say that SOA efforts in recent years have laid the groundwork that make clouds work -- interoperability, reuse, and the idea that loosely coupled services and applications can operate independently of each other, within and across firewalls.
And I would argue that SOA is the private cloud, and the public cloud is one massive SOA. Pretty exciting stuff if you ask me.
Stacey also provides follow-up perspectives on HP's presentations here and here. Some interesting takeaways: "HP thinks IT will be delivered as a service by thousands of different providers, who in turn will be cobbled together to offer even more services" -- in essence, cobbled together by a single vendor. "Kind of like having a single chef make the world’s supply of macaroni and cheese," she observes. "The providers behind these monolithic clouds could scale while still making a profit and offer service guarantees because they would control the infrastructure. Others could build services on top of them, and data could then be shared across different applications." Not quite there yet, Stacey says -- let's hold that thought for now.
Plus, there are still reasons for enterprises to be nervous about cloud computing. There are issues with a lack of portability and vendor lock-in -- "yet another reason that enterprises may want to keep their data out of the clouds for a bit longer."