The Amazon Web Services (AWS) announcement of the Virtual Private Cloud (VPC) offering has just made Cloud Computing more attractive to the enterprise. Most companies I talk with are interested in the "Cloud", but beyond a few SaaS apps and perhaps some dev/test they are not ready for any big change to their corporate IT infrastructure. On the other hand many of those same companies are currently or projected to be capacity limited in their own data center based on space or power limitations.
Many companies will opt to move or expand into a Co-lo (Co-location) facility which provides dedicated space, power and bandwidth. This solves the space and power problem but most of the same costs of computing are just moved to a remote facility. The expensive data center facility cost is shared among other companies but the Server, Storage and Networking are all dedicated. The promise of the Cloud and particularly IaaS (Infrastructure as a Service) like Amazon EC2 is sharing computing and facility costs, having capacity available on demand, and only paying for what is used.

The obstacles to IaaS offerings that I hear most often include security concerns and the desire keep the corporate data and or legacy infrastructure in place. Making a massive move from premise to Cloud is not desired or warranted.  On the other hand enabling a Premise Plus Cloud solution in a secure fashion and using it only for expansion or overflow capacity could be appealing for many companies. Essentially this is what Amazon is offering with VPC, a dedicated secure network extending from a company data center into the Amazon Cloud with isolated VM's available on demand.  
For Citrix Customers this could be particularly attractive for expanding XenApp farms or centralizing new applications on XenApp without the prerequisite facility and capital costs. Customers can bring their own XenApp licensees to VPC or point back to existing license server on premise. We have been collaborating with Amazon AWS to build and test XenApp servers in VPC to validate and number of scenarios and use cases. In addition we have made dedicated Amazon Machine Image ( AMI ) templates available with XenApp 5 preinstalled and ready to launch.  Citrix C3 Blueprints are also now available to assist companies that want to start to evaluate the new offering. ( Note: the service is currently in Beta )

For Citrix this announcement represents another progressive move as a leader and enabler of Cloud Computing. Amazon EC2 based on the Xen Hypervisor has already made EC2 ubiquitous with start-ups and the undisputed leader in Public Clouds, VPC with XenApp now represents a significant opportunity for Enterprise IT. The Citrix Cloud Center ( C3 ) portfolio will continue to enable IT and Cloud providers to exploit the promise of the Cloud, stay tuned..

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