GCP Networking

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Resource in GCP

Global 

• Can be accessed by any other resource, across regions and zones 

• Creating VPC is a global operation because a network is a global resource 

• Different from AWS and Azure because the VPC and routing is global, not within a region 

Regional 

• Can be accessed only by resources in the same region 

• Reserving an IP address is a regional operation 

Zonal  

• Can be accessed only by resources in the same zone 

• Disks can be attached to computers in the same zone   

GCP Projects

• Projects are the fundamental organizational structure 

• GCP resources must belong to a project 

• Made up of settings, permissions, and other metadata that describe applications 

• Contains the computing, storage, and networking resources 

• A project can’t access other projects resources unless you use 

  • Shared VPC 

  • VPC Network Peering 

Basic GCP Network Components  

• GCP Regions and Zones 

• VPC/Subnets 

• VPC Peering 

• Implicit Routing 

• VPN Gateway 

VPC Network 

• Global Routing: 

  • VPC is a global resource 

  • All the subnets irrespective of region are inherently routable within a VPC 

• Subnets/CIDR are a regional resource  

• Projects can contain multiple VPC networks 

Routes in GCP 

• Routes created by GCP for users are system generated routes 

  • Default route 

  • Subnet gateway 

• User Defined Route 

  • Static Routing 

  • Dynamic Routing 

Transit (Inter-VPC) Networking 

• Lacks native transit solution to interconnect VPC’s 

  • VPC peering preferred 

  • Preaching single VPC 

• VPC Peering 

  • Same qualities as other CSP’s 

  • All preprogrammed routes from the two VPC’s are announced to each other 

  • Used to connect multiple VPC’s  

  • Non-transitive 

Cloud Interconnect 

• Connect your On-Prem network to your VPC network through a private connection 

• Limitation: Not encrypted 

• Dedicated Interconnect 

  • Enables users to connect existing network to the VPC network through a highly available, low latency, enterprise grade connection