Wed, May 27, 2009 — CIO — Cloud infrastructures are a highly efficient evolution of server virtualization and the scale-out deployment model—but companies should note this evolutionary path isn't a fit for all applications. That being said, cloud computing platforms are more than just shared, multi-tenant infrastructures on the public Internet. Three infrastructure-as-a-service cloud deployment options are available to enterprises today, each with unique characteristics and economics that can help optimize application and service deployment objectives:

1. Public clouds. These deliver the best economies of scale, but their shared infrastructure model can limit configuration, security, and SLA specificity, making them a less-than-ideal fit for services using sensitive data that is subject to compliancy or safe harbor regulations.

2. Internal clouds. These sit within your data center and behind company-built protections, but they typically have modest economies of scale due to funding limitations and tend to be less automated.

3. Hosted clouds. Hosted clouds run at a service provider on resources that are walled off with enterprise-class protections but managed as a pool. These fall between the first two options, providing more custom protections like an internal cloud but with the greater economies of scale of being a service from a cloud provider.

Enterprises should build a strategy that leverages all three options via virtual private cloud technologies, which will result in a hybrid cloud strategy that optimizes business service deployment efficiencies.

Virtual private cloud is a technique for extending your organizational trust boundaries over a series of resources regardless of their deployment. It builds off the basic concept of a virtual private network (VPN), but is a more robust networking concept that lets you define and control addressing, topology, protocols, and encrypted communications for instances deployed to cloud computing platforms.

Virtual private cloud technology defines the network security boundaries for the business service and the locations (types of deployments) where elements of these services can be placed or moved. These solutions can be enabled by two types of offerings: 1) those that focus on the network security layer; and 2) those that abstract the application tier across cloud deployment boundaries.

The evolution of cloud computing and virtual private cloud technologies add to the ever widening portfolio of infrastructure deployment options that help enterprises match the infrastructure to the needs of the application more efficiently and cost effectively than has been possible before. Here are a few tips to ensure the integration between these deployment infrastructures deliver the greatest value:

1. View cloud platforms as a portfolio of deployment options.

Look at creating a portfolio of cloud resources, composed of public, internal, and hosted cloud deployments linked together with traditional deployments via virtual private cloud. Look for ways to optimize—and automate—the deployment and management of your business services where most appropriate based on the application requirements and business/IT policies. You definitely want to learn to walk in cloud environments before going hog wild and spreading services across lots of cloud deployments but, as you gain experience, begin to craft a strategy that streamlines deployment expenses in much the same way that you optimize your Web site deployment. The ultimate goal is to speed IT service delivery while reducing costs.

2. Partner with enterprise architects to get the deployment model right.

Your Web infrastructure likely spans your data center, a content delivery network, and a hosting provider—each chosen for what they do best and connected to deliver optimum performance and customer experience. Approach cloud computing in the same way. Work with your enterprise architects to determine what types and portions of applications and what data sets are the best fit with the specific cloud deployment options discussed here and create joint policies to guide appropriate use as new applications are built or readied for the cloud.

3. Build a security model and policy with your CISO.

Work with your security and risk management professionals to understand what protections must be taken for what types of data so you can determine where applications can safely be deployed. Create and publish this as a policy for all application development professionals to help guide their use of cloud resources. Also, use this guide to set the SLAs for your private cloud, whether internal or hosted.

4. Ask your hosting providers about their cloud plans.

You likely have relationships with one or more hosting providers today. Get an understanding of what cloud services they provide or plan to provide to you in the future. Determine if a hosted cloud is a possibility from these vendors, what degree of configurability is available, and if they can provide virtual private cloud services between your data center and their cloud offerings.

James Staten is a Principal Analyst at Forrester Research, advising IT Infrastructure & Operations professionals on the transformation of the server and data center into more efficient, business-focused ecosystems. He is an expert on cloud computing. To obtain free, related research from Forrester (registration required), please visit: www.forrester.com/ciodatacenter.

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