Subnetwork
A subnetwork is a logical subdivision of an IP network with its own address range, routing scope, and network configuration.
Google Anthos in Action
An IP subnet is a contiguous range of IP addresses defined by a network prefix for assigning and routing network addresses.
- How it is used
- Allocates address capacity for nodes, Pods, and Services when planning Anthos GKE clusters.
- How deep it goes
- Works through address pools, per-node Pod subdivision, and sizing inputs rather than IP subnet theory.
- Examples
- Uses a 10.0.0.0/16 Pod CIDR divided into successive /24 node ranges and tables for node, Pod, and Service capacity.
- What you can do after
- Operate/configure it by sizing cluster address pools and checking whether planned VPC-native allocations overlap.
Acing the CCNA Exam: Volume 1 Fundamentals and Protocols
A subnet is a logical subdivision of an IPv4 network address space with its own network address and prefix length.
- How it is used
- Uses IPv4 address blocks to create appropriately sized networks, configure interfaces, solve CCNA subnetting problems, and segment LANs.
- How deep it goes
- Explains CIDR, borrowed bits, subnet attributes, capacity formulas, FLSM, VLSM, and Cisco IOS configuration, while deferring traffic filtering to access control lists.
- Examples
- Demonstrates /24, /16, /8, /23, and /24 VLSM scenarios through address calculations, diagrams, tables, and Cisco IOS interface commands.
- What you can do after
- Apply it via Cisco IOS by calculating subnet ranges, selecting prefix lengths, assigning interface addresses, and verifying host capacity.
Read how Acing the CCNA Exam: Volume 1 Fundamentals and Protocols explains subnetwork →
Amazon Web Services in Action, Third Edition: An in-depth guide to AWS
A subnet is a logical subdivision of an IP network with its own address range and routing boundary.
- How it is used
- Separates internet-facing components from backends within a VPC to control exposure.
- How deep it goes
- Works through IPv4 address ranges, routing roles, and EC2 placement, while deferring IPv6 configuration.
- Examples
- Uses a three-subnet VPC with a public proxy, private backend, and public subnet reserved for a NAT gateway.
- What you can do after
- Build it from scratch with CloudFormation by assigning address ranges and placing EC2 instances in public or private subnets.
Terraform in Depth: Infrastructure as Code with Terraform and OpenTofu
A subnet is a logically segmented portion of an IP network with its own address range.
- How it is used
- Uses subnet IDs to place instances in existing networks and CIDR blocks to create segmented VPC networks.
- How deep it goes
- Works through subnet input validation and a two-segment Terraform module, including address division and connectivity dependencies.
- Examples
- Shows an instance configured with `var.subnet_id` and modules that divide address space into public, private, and isolated subnets.
- What you can do after
- Build it from scratch: configure a subnet-selectable instance module or create segmented AWS subnets with Terraform.
Microsoft Azure in Action
A subnet is a subdivision of a virtual network with its own address range and network configuration.
- How it is used
- Separates Azure resources inside a VNet for organization, service delegation, and subnet-specific security rules.
- How deep it goes
- Defines nonoverlapping address ranges, explains sizing trade-offs, and demonstrates PowerShell creation and delegation without detailing security-rule configuration.
- Examples
- Uses a city-and-suburb analogy, a 10.0.1.0/24 address prefix, and PowerShell commands delegating a subnet to Azure SQL.
- What you can do after
- Operate/configure it with Az PowerShell by adding a subnet, saving its VNet, and optionally delegating it to Azure SQL.
Related concepts
- subnettingproduced by · Subnetting is the division of an IP address space into smaller logical networks by extending the network prefix.
- VPCpart of · A virtual private cloud is a logically isolated virtual network provisioned within a cloud provider's shared infrastructure.
- routing tableconfigured by · A routing table is a data structure containing rules that map destinations, conditions, or peers to paths, next hops, services, or other forwarding targets.
- private subnetincludes · A private subnet is a subnet whose resources lack direct connectivity or reachability to the public internet.
- network security groupconfigured by · A network security group is an Azure access-control resource that filters inbound and outbound network traffic using prioritized security rules.
These guides are generated from the text of Manning books by Manning's knowledge graph and link to the sections they draw on. The full books are available on liveBook and at manning.com.