if the location of a stored object has changed, the system needs to be smart enough to go looking for it elsewhere, rather than choking or giving up.
To enable loose coupling, finally, cloud storage systems need to utilize minimal “shared knowledge,” meaning information about where data objects are stored. If that information is replicated across dozens of systems, it means each copy has to be updated every time an object’s location changes, which slows everything down.
Feinberg says designing Atmos was largely a matter of coming up with new ways to store and manage metadata—that is, data about data—as well as ways to let users set policies for how different types of data should be stored. A company might set up a business rule, for example, forcing confidential data to be stored within a company’s internal cloud, while non-confidential data could be shared across public clouds.
While it’s got decades of experience in storage arrays, EMC’s expertise is mainly in tightly coupled systems built for speed rather than resilience. So it didn’t have the parts for Atmos just sitting around, Feinberg says. “Much to Joe Tucci’s chagrin, we had to build it from scratch,” he says. (Tucci is EMC’s chairman, president, and CEO.)
But now that it’s built, companies that buy it won’t have to say “no” so often to employees who have ideas for new Web-based products or services, says Feinberg. “The cloud is creating this dilemma,” he says. “Companies have rogue developers who can’t get access to their own centralized infrastructure, or who feel like they don’t need it and just take out their credit card and have a successful deployment on X, Y, or Z public cloud. In certain cases that might make sense, but in other cases it might put their IP at risk, or create a governance risk. Our story is to enable IT organizations to say yes, by allowing them to buy a product that has the same capabilities that they’d have over the Internet.”
For customers who still need to run tightly coupled enterprise applications internally, but simply want to do it more efficiently in cloud-like environments, EMC has a separate but related solution: the so-called Virtual Computing Environment (VCE) Coalition, under which EMC, its virtualization subsidiary VMware, and networking giant Cisco are working together to
