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The virtual data center and a ladder to the cloud

December 31, 2009 - 3 Comments

Data centers have received a steady stream of technological updates in recent years, leading to faster, cheaper, and more automated operations.  I think of these changes like a ladder, from the conventional data center of five or ten years ago, up to cloud computing today.

Ladder from virtual data center to cloud

From the bottom rung of the ladder up, there have been advantages for data centers taking each step:

  • A consolidated data center uses storage area networks and basic hypervisors to cut the number of disk systems and physical servers needed to support applications.  Simple consolidation yields large savings in capital expenses, speeds up provisioning of servers as virtual machines, and makes server disks easier to snapshot and recover if anything goes wrong.
  • A virtual data center relies on advanced hypervisor features to make operations more flexible and dynamic.  Hot migration of virtual machines eliminates most scheduled downtime, automates resource management, and enables self-service lab management and staging that accelerates application development and deployment.  Most data centers today are or are becoming virtual data centers.
  • A private cloud takes automation much further, providing complete self-service for application deployment and scaling.  Cloud technology uses software to do many of the routine jobs of today’s system administrators, making IT far more agile in response to business needs.  Clouds also offer fine-grained accounting of resource use, permitting precise chargeback of costs within the organization.
  • A public cloud has all the facilities of the private cloud, plus the sharing of resources among many customers.  This requires large pools of servers and storage, and provides each customer the experience of limitless scalability on-demand and without prior planning.  Public clouds also charge for use in small increments, so that an organization can replace its fixed capital costs with smoothly varying operating costs.  Without a public cloud, capital equipment costs are normally set to accommodate the maximum level of use, so public clouds are often much less expensive.

A company facing this technology ladder does not have to take each step; it can jump more than one step at a time.  A conventional data center that starts making changes today is likely to jump straight to the virtual data center or beyond; a number of new companies have built their IT directly in the public cloud.  

Many enterprise customers today are working in the virtual data center model.  For them, the coming year will be about expanding and getting the maximum value out of their virtual data center.  They will concentrate on simplifying their operations and increasing the level of automation.  And they will have their eyes on cloud technology, wanting to ensure that they can take the next step when the time comes.

Cisco designs equipment to work at each step along the ladder.  The network is a platform that should  support each data center model with minimum disruption as enterprises change.   In the coming year, you can expect to see new equipment that supports the flexibility, simplification, and automation demands of today’s virtual and cloud data centers.

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  1. Thanks for the comments. Zen, I think some companies are moving directly from conventional to public clouds -- but it's a lot more work than moving just one step at a time!D C Canada, I agree that geography can be very important. The jurisdiction of a data center's location affects privacy, data retention rules, and more. In fact, this is a big reason why organizations are interested in private clouds -- to get the flexibility and efficiency of IaaS cloud computing, while keeping the equipment and data in their own buildings.

  2. Very good illustration - but the Cloud is not for everyone. One thing people need to understand is privacy related issues in particular due to Bush's Patriot Act. The Cloud isn't limited by geography which opens up a big can of worms related to data privacy.

  3. This is a great classification because there is a definite gap between a conventional data center and a cloud. You cannot jump from an existing data center to a cloud in one leap. I have two comments on this. The first is that it is sometimes hard to distinguish one from the other, especially at the boundary. The second is that private and public clouds are developed for different reasons, and I am not sure whether the public cloud is an evolution of the private cloud. Nevertheless, it is good to have a classification like this.However, it is not important to define exactly where you stand but to take appropriate action to plan the jump to the next stage of cloudization.A complete comment is in