A virtual private cloud (VPC) is a logically isolated and secure private cloud that's hosted within a public cloud environment. Despite not being physically separated from other public-cloud tenants, a VPC is segmented. It uses dedicated computing resources and prevents sensitive data from being shared thanks to network-based isolation.
VPCs primarily run on public-cloud infrastructure. VPC users gain all the benefits of public clouds — namely scalability, advanced security, high availability, and centralized management — while working like a private instance. Teams can still run their applications, code, websites, and data workflows within this environment as they normally would elsewhere. Organizations have "ownership" over their own portion of the cloud without breaking the bank.
AWS is credited with creating the first publicly available VPC in the late 2000s. Beforehand, VPCs comparable to today's didn't exist. Companies such as Microsoft, Cisco, and others offered VPN tunneling to loosely mimic this functionality, but none offered true isolation hosted directly on cloud infrastructure.
How does a virtual private cloud (VPC) work?
VPC users still have to reserve capacity from their chosen cloud vendor, such as AWS, much like they would for the public cloud. This includes computing resources and block storage — which divides customer data (files, database entries, etc.) into equally-sized chunks and places them into a physical storage location. This is optimized for reliable, low-latency access at any time.
Additionally, setting up a VPC may require organizations to purchase and implement the following:
NAT or transit gateways – Allows private cloud instances and their services to connect to outside services over the internet, while guarding against unwanted, incoming connections
IP address management (IPAM) – Allows team to track and manage IP addresses across all connected network devices in the TCP/IP stack
Traffic management and mirroring – Allows the system to capture, copy, and compile real network traffic remotely for real-time monitoring, while boosting security
IPv4 and IPv6 addresses – Allows teams to assign public IP addresses to network devices, letting them connect to the internet. You can also reserve sequential IP address blocks to simplify networking and allowlisting for ACL use. Subnets can help with this while preventing other devices from claiming your preferred IPs.
VPC route server – Routes traffic to safe and healthy instances while providing automatic failover
VPC peering – Allows the VPC to handle traffic and data routing between combinations of local and global availability zones
VPC encryption – Keeps stored and traveling data safe from attackers
Load balancers – Enables teams to intelligent route application traffic between servers and maximize resource efficiency
While some of these components are configured by the customer, the vendor assumes the bulk of the responsibility for infrastructure maintenance and security. This is a major selling point for VPCs. By using an infrastructure as a service (IaaS) vendor such as AWS, teams can offload a large chunk of tasks that might accompany a private cloud or hybrid-cloud deployment.
Each cloud provider offers a different pricing model for VPCs and related services. Some charge by the hour, per GB of data processed over a defined time period, or for chunks of guaranteed capacity. This last option lets teams pay reactively as they go, but can make rapid auto-scaling a little harder.
Otherwise, virtual private clouds rely on a combination of subnets, VLANs for locally linking computing devices, private endpoints for connectivity, BGP routing tables, and VPNs to tunnel remote traffic safely.
Virtual private cloud (VPC) use cases
Because of their cost-effectiveness and flexibility, VPCs can support a number of computing goals. Organizations can use VPCs for the following use cases:
Hosting applications and other services
Migrating or deploying applications across multi-cloud environments
Support high-performance computing (HPC) workloads through rapid resource allocation
Meet or exceed government regulatory compliance standards
Disaster recovery and failover planning
DevSecOps automation and software development lifecycle (SLDC) optimization
IoT connectivity and secure edge computing
What are the benefits of virtual private clouds (VPCs)?
VPCs offer plenty of advantages to organizations that rely on them:
They're logically secure and compliant, since sensitive data is shielded from other tenants and external environments. You can also enforce granular access rules via security groups.
They're compatible with on-premises deployments, letting teams set up hybrid-cloud environments more effectively via VPN.
They're generally less costly than private clouds, as you're still performing workloads atop public cloud infrastructure (which is partly subsidized by other customers).
They're highly available and highly performant versus alternative options.
They're highly scalable since customers can request additional computing resources anytime.
They're flexible and enable easier modernization, as VPCs can be implemented dynamically in response to use case needs and runtime conditions.
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Does HAProxy support virtual private clouds (VPCs)?
Yes! HAProxy One — the world's fastest application delivery and security platform — enables teams to manage, secure, and observe all your application traffic in any environment. HAProxy One connects services distributed across cloud platforms and networks seamlessly via our universal mesh solution. Plus, you can even implement load balancing and security features within your AWS VPC.
To learn more about VPC support in HAProxy, check out our Rate limiting based on AWS VPC ID blog post.