Google Cloud VPC: Your Private Network in the Cloud

Google Cloud Platform’s Virtual Private Cloud (VPC) lets you create a globally scalable, private network within the Google Cloud infrastructure. It’s the foundation for your GCP resources, providing isolation, security, and control.

Key GCP VPC Components:

Projects:

• In GCP, projects are the top-level organizational unit. Your VPC networks reside within a specific project. This enables resource management, billing, and access control.

VPC Networks:

• A GCP VPC network is a global resource, meaning it spans all regions. It defines the overall IP address space for your virtual network.
• You can create multiple VPC networks within a project, allowing for further isolation and segmentation.
• GCP offers both auto mode and custom mode VPC networks. Auto mode automatically creates subnets in each region, while custom mode gives you full control over subnet creation.

Subnetworks (Subnets):

• Subnets are regional resources, meaning they exist within a specific region. They are subdivisions of your VPC network.
• Each subnet has a defined IP address range.
• GCP subnets can be either:
  - External (Public) Subnets: Resources in these subnets can communicate with the internet, typically through an Internet gateway.
  - Internal (Private) Subnets: Resources in these subnets do not have direct internet access, enhancing security. They can access the internet using Cloud NAT.

Routes:

• GCP uses routes to determine how network traffic is directed within your VPC network.
• Routes define the destination for traffic and the next hop for that traffic.
• You can create custom static routes or rely on automatically generated routes.

Firewall Rules:

• GCP Firewall Rules control network traffic in and out of your VPC network.
• They are applied at the network level and allow or deny traffic based on IP addresses, ports, and protocols.
• They are stateful, meaning that return traffic for allowed outbound traffic is automatically allowed.

Cloud Router:

• Cloud Router enables you to dynamically exchange routes between your VPC network and your on-premises network using Border Gateway Protocol (BGP).

Cloud NAT:

• Cloud NAT (Network Address Translation) allows resources in private subnets to access the internet without having public IP addresses.

VPC Network Peering:

• This feature allows you to connect two VPC networks in the same or different projects, enabling resources in those networks to communicate with each other.

Shared VPC:

• Shared VPC allows you to share a VPC network from a host project with service projects, enabling centralized network management.

By leveraging these GCP VPC components, you can build a secure, scalable, and highly customizable network environment for your cloud applications.