Benefits

Security

You can use the SNAT feature of NAT gateways to protect ECS instances. After you configure SNAT, ECS instances in the specified VPC can access external networks. Unsolicited connection requests from external networks are denied. SNAT shields the ports that the ECS instances use to communicate with the Internet. This protects the ECS instances from external attacks.

High performance

NAT gateways are distributed gateways that use the software-defined networking (SDN) technology. Each NAT gateway provides a throughput capacity of up to 100 Gbit/s, and can serve a large number of Internet applications.

Cost-effectiveness

You can resize a NAT gateway, and change the number and specification of elastic IP addresses (EIPs) that are associated with the NAT gateway. NAT gateways also support the pay-as-you-go billing method. Therefore, you can use NAT gateways to withstand traffic fluctuations.

Zone-based high availability

You can deploy a NAT gateway across zones to achieve high availability. When one zone is down, network traffic is distributed to another zone to prevent service interruptions.