What is a peering connection in Google Cloud?

A peering connection in Google Cloud refers to a way of enabling private communication between two Virtual Private Cloud (VPC) networks. This connection allows resources in one VPC network to communicate with resources in another VPC network as if they were part of the same network, all while maintaining the security and isolation inherent to each VPC. The traffic between the peered VPCs is private and does not leave the Google Cloud network infrastructure, thus enhancing security and performance.

This private communication is advantageous for a variety of scenarios, such as sharing services across different departments or projects within an organization, or enabling collaboration between different applications hosted in separate VPCs without exposing this communication to the public internet.

The other choices represent concepts that do not specifically define peering connections in the context of Google Cloud. A connection to external providers is linked to services outside Google Cloud rather than internal VPC communication. Segmenting subnets pertains to organizing IP address ranges within a single VPC rather than connecting separate VPCs. A protocol for data encryption refers to security practices that protect data but does not address the specific nature of how VPCs interconnect.