AWS Lambda is also inherently fault-tolerant. A function can be configured to run inside one of your own VPCs or an AWS-managed VPC. If you choose to run in your own VPC, you can also choose which subnets a function can be executed in. If you have selected subnets across multiple availability zones (AZs), then the Lambda service will pick which subnet to execute the function in.

The Lambda service attaches an elastic network interface to the function during the initialization process before the code executes, and the function receives a private IP address. It's important to note though that a Lambda function can never be assigned a public IP address, so you can't make any inbound connections, nor can you make a function listen in on a port.