VPC Networking and Security Groups

A Virtual Private Cloud (VPC) is a logically isolated network on Alibaba Cloud where you deploy your cloud resources. Understanding VPC networking is essential for building secure, well-architected applications.

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What is a VPC?

A VPC is your own private network within Alibaba Cloud. It provides:

• Isolation — your resources are logically separated from other tenants
• Control — you define the IP address range, subnets, route tables, and gateways
• Security — use security groups and network ACLs to control traffic

Every VPC is region-specific — it exists within a single Alibaba Cloud region.

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VPC Components

CIDR Block

When creating a VPC, you define a CIDR block (the IP address range):

CIDR Block	Usable IPs	Common Use
10.0.0.0/8	~16 million	Large environments
172.16.0.0/12	~1 million	Medium environments
192.168.0.0/16	~65,000	Small environments

vSwitches (Subnets)

A vSwitch is a subnet within a VPC. Each vSwitch: