Virtual private cloud
A Virtual Private Cloud (VPC) is an on demand configurable pool of shared computing resources allocated within a public cloud environment, providing certain level of isolation between the different organizations (denoted as users hereafter) using the resources. The isolation between one VPC user and all other users of the same cloud (other VPC users as well as other public cloud users) is achieved normally through allocation of a Private IP Subnet and a virtual communication construct (such as a VLAN or a set of encrypted communication channels) per user. In a VPC solution, the previously described mechanism, providing isolation within the cloud, is accompanied with a VPN function (again, allocated per VPC user) that secures, by means of authentication and encryption, the remote access of the organization to its VPC cloud resources. With the introduction of the described isolation levels, an organization using this service is in effect working on a 'virtually private' cloud (i.e. as if the cloud infrastructure is not shared with other organizations), and hence the name VPC.
VPC is most commonly used in the context of cloud infrastructure services (IaaS). In this context, the infrastructure provider, providing the underlining public cloud infrastructure, and the provider realizing the VPC service over this infrastructure, may be different vendors.
Amazon Web Services launched Amazon Virtual Private Cloud on 26 August 2009, which allows the Amazon Elastic Compute Cloud service to be connected to legacy infrastructure over an IPsec virtual private network connection.
In AWS, VPC is free to use, however users will be charged for any Virtual Private Networks (VPN) they use. EC2 and RDS instances running in a VPC can also be purchased using Reserved Instances, however will have a limitation on resources being guaranteed.
Google App Engine supported similar functionality via their Secure Data Connector product which was launched on 7 April 2009. Google deprecated this service on 14 March 2013 and no longer accepts new signups. The service is expected to continue running for existing users until (at least) 20 April 2015.
FortyCloud is an example for a VPC solution that can be provided over 3rd parties' public cloud infrastructures, such as AWS EC2.
HP offers a Enterprise Cloud Services-Virtual Private Cloud. offering as part of their Converged Cloud Solutions Platform that integrates Private Cloud, Managed Cloud, and Public Cloud Services based on OpenStack.
Regional virtual private clouds also exist, such as cloud.ca, a canadian virtual private cloud platform. 
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- Amazon launches Virtual Private Cloud service
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- Cloud computing : Amazon lance une offre de nuage privé
- Secure Data Connector (Deprecated)
- Amazon Virtual Private Cloud - a commercial virtual private cloud offering by Amazon Web Services
- French Virtual Private Cloud - a commercial virtual private cloud offering by CloudSystem
- Google Secure Data Connector - virtual private cloud functionality for Google App Engine
- VMware vCloud Virtual Private Cloud OnDemand - on-demand virtual private cloud offering by VMware vCloud