Application Scenarios

VPC allows you to provision logically isolated virtual private networks for cloud resources, such as cloud servers, containers, and databases. Additionally, you can use VPC and other networking services to set up networks to meet different requirements.

Building a Highly Secure Cloud Network

You can deploy applications on instances in a VPC and configure security groups and network ACLs to protect these instances.

A security group protects the instances in it.
A network ACL protects the entire subnet. After a subnet is associated with a network ACL, all instances in the subnet are protected by the network ACL.

In the figure below, your application is deployed on the ECSs in a subnet (Subnet-A01), and the database servers are deployed in another subnet (Subnet-A02) that is isolated from the Internet. To protect these servers, you can configure security groups and network ACLs to control inbound and outbound traffic.

Figure 1 Building a secure and private cloud network

For more information, see Access Control Overview.

Building a Cloud Network for Isolating Services

If you want to isolate services, you can deploy them in different VPCs, as resources in separated VPCs cannot directly communicate with each other.

Figure 2 Building a cloud network for isolating services

If two VPCs need to communicate with each other, you can use a VPC peering connection or enterprise router to connect the two VPCs. For details, see Connecting VPCs.

Building a High-Availability Load Balancing Network

To handle a large number of concurrent requests from the Internet, you can deploy multiple ECSs in a VPC and use ELB to distribute requests across these servers to improve service stability and availability.

Figure 3 Building a high-availability load balancing network

For more information, see Using ELB to Distributing Traffic over the Internet.

Building a Hybrid Cloud Network

If your cloud and on-premises services want to communicate with each other, you can use VPN or Direct Connect to build a hybrid cloud network.

Hybrid cloud networking using VPN and VPC
In Figure 4, some workloads have been migrated to a VPC (VPC-A), and some workloads are still running on on-premises servers. With a VPN connection, on-premises servers can quickly access the cloud resources in the VPC. Compared with Direct Connect, VPN is easier to configure and cost-effective.
Figure 4 Connecting a VPC to an on-premises data center using VPN
Hybrid cloud networking using Direct Connect and VPC
In Figure 5, some workloads are running in a VPC (VPC-A) on the cloud, and some are running in the on-premises data center. A Direct Connect connection connects the on-premises data center to the cloud. Direct Connect connections are faster and more stable than VPN connections.
Figure 5 Connecting a VPC to an on-premises data center using Direct Connect