Virtual Private Cloud (VPC) allows you to create a custom private virtual network on Alibaba Cloud. VPCs are logically isolated from each other. You can create and manage your VPCs. For example, you can configure CIDR blocks, subnets, route tables and network policies of your network architecture to ensure the security of your data and applications. You can scale the resources in your VPCs based on your business workloads to support the business continuity, changes and growths. Such resources include Elastic Compute Service (ECS) instances, Server Load Balancer (SLB) instances, and ApsaraDB RDS instances. VPC allows you to better control your resources access and improve data security and flexibility.
Components
Each VPC consists of at least one vRouter, one private CIDR block, and one vSwitch.
Private CIDR blocks
When you create a VPC and a vSwitch, you must specify a private IP address range for the VPC in CIDR notation. You can specify one of the standard private CIDR blocks that are listed in the following table as the private CIDR block of a VPC, or use a custom CIDR block. For more information, see Plan networks.
CIDR block
Description
192.168.0.0/16
Number of available private IP addresses (excluding IP addresses reserved by the system): 65,532
172.16.0.0/12
Number of available private IP addresses (excluding IP addresses reserved by the system): 1,048,572
10.0.0.0/8
Number of available private IP addresses (excluding IP addresses reserved by the system): 16,777,212
Custom CIDR block
You can use a custom CIDR block, except 100.64.0.0/10, 224.0.0.0/4, 127.0.0.0/8, 169.254.0.0/16, and their subsets.
vRouters
A vRouter is a virtual router that connects all vSwitches in a VPC. A vRouter serves as a gateway between a VPC and other networks. After you create a VPC, a vRouter is automatically created for the VPC. A vRouter is associated with at least one route table. For more information about route tables, see Route table overview.
vSwitches
A vSwitch is a basic network device of VPC. You can use a vSwitch to connect different cloud resources. After you create a VPC, you can create vSwitches to divide the VPC into one or more subnets. vSwitches that are in the same VPC can communicate with each other. To improve service availability, you can deploy your applications in vSwitches that belong to different zones. For more information about vSwitches, see Create and manage a vSwitch.
VPC planning
Before you use a VPC, you must plan your VPC based on your business requirements. For more information, see Plan networks.
VPC connections
Instances that reside in VPCs can connect to the Internet, other VPCs, and local data centers. Alibaba Cloud provides various solutions to meet the requirements of the connections. For more information, see Manage VPC connections.
Operations required for VPCs
To use cloud resources in VPCs, you must create a VPC and a vSwitch.
For more information about VPCs, see What is a VPC?