Definition: Isolated virtual network within AWS that provides full control over network configuration, subnets, and cloud resource security.
— Source: NERVICO, Product Development Consultancy
What is Amazon VPC
Amazon Virtual Private Cloud (VPC) is the AWS networking service that allows creating a logically isolated virtual network within the Amazon cloud. Within a VPC, teams have full control over network configuration: IP address ranges, subnets, route tables, and network gateways. AWS resources such as EC2 instances, RDS databases, and ECS containers are deployed within a VPC, providing network isolation and granular control over who can access which resources.
How It Works
A VPC is defined with a CIDR block that establishes the available IP address range. Within the VPC, public subnets (accessible from the internet through an Internet Gateway) and private subnets (without direct internet access) are created. Security groups act as instance-level firewalls, controlling inbound and outbound traffic by port and protocol. Network ACLs provide an additional layer of control at the subnet level. To connect a VPC with corporate networks, VPN connections or AWS Direct Connect are used. VPC Peering enables direct communication between VPCs without traversing the internet.
Why It Matters
Network security is a fundamental requirement for any production application. VPC ensures that critical resources like databases and application servers are not directly exposed to the internet. For companies with regulatory or compliance requirements, VPC provides the network isolation needed to meet standards such as SOC 2, HIPAA, or GDPR. Without VPC, implementing secure multi-tier architectures in the cloud would not be possible.
Practical Example
A healthcare company deploys its application in a VPC with three subnet tiers. The public tier contains only the load balancer that receives internet traffic. The application tier in private subnets hosts application servers that only accept traffic from the load balancer. The data tier in isolated subnets contains the RDS database that only accepts connections from the application tier. This design ensures that the database with patient data is never directly accessible from the internet.