In this section of the course, we’re going
to explore how Google Compute Engine works with a focus on virtual networking. Many users start with Google Cloud by defining
their own virtual private cloud inside their first Google Cloud project or by starting
with the default virtual private cloud. So, what is a virtual private cloud? A virtual private cloud, or VPC, is a secure,
individual, private cloud-computing model hosted within a public cloud – like Google
Cloud! On a VPC, customers can run code, store data,
host websites, and do anything else they could do in an ordinary private cloud, but this
private cloud is hosted remotely by a public cloud provider. This means that VPCs combine the scalability
and convenience of public cloud computing with the data isolation of private cloud computing. VPC networks connect Google Cloud resources
to each other and to the internet. This includes segmenting networks, using firewall
rules to restrict access to instances, and creating static routes to forward traffic
to specific destinations. Here's something that tends to surprise a
lot of new Google Cloud users: Google VPC networks are global. They can also have subnets, which is a segmented
piece of the larger network, in any Google Cloud region worldwide. Subnets can span the zones that make up a
region. This architecture makes it easy to define
network layouts with global scope. Resources can even be in different zones on
the same subnet. The size of a subnet can be increased by expanding
the range of IP addresses allocated to it, and doing so won’t affect virtual machines
that are already configured. For example, let’s take a VPC network named
vpc1 that has two subnets defined in the asia-east1 and us-east1 regions. If the VPC has three Compute Engine VMs attached
to it, it means they’re neighbors on the same subnet even though they’re in different
zones. This capability can be used to build solutions
that are resilient to disruptions yet retain a simple network layout.