Learning path · Foundational
Networking Fundamentals
Work up from frames and addresses to routing, segmentation and enterprise edge services.
What you will be able to do
- Subnet confidently and design address space that summarises cleanly
- Explain DNS and DHCP behaviour well enough to diagnose failures
- Describe where VLANs, firewalls and load balancers each apply policy
The path
Work through these in order.
- 01OSI Model
The vocabulary for isolating faults by layer.
A seven layer conceptual model that separates network communication into distinct, independently replaceable functions.
- 02TCP/IP
How delivery, ports and reliability actually work.
The protocol suite that actually runs the internet and virtually every enterprise network, organised into link, internet, transport and application layers.
- 03Subnetting & CIDR
Prefix design as an architecture decision.
Dividing IP address space into right sized networks using prefix length notation, so that routing, segmentation and growth all remain manageable.
- 04DNS
Resolution, records and the most common failure modes.
The Domain Name System is the distributed, hierarchical directory that resolves names to addresses and service records for nearly every other service.
- 05DHCP
Lease behaviour, relays and rogue server risk.
Dynamic Host Configuration Protocol automatically issues IP addresses and network configuration to clients as they join a network.
- 06Switching & VLANs
Segmentation and its limits as a security control.
Virtual LANs partition one physical switched infrastructure into multiple isolated layer 2 broadcast domains.
- 07Routing
Path selection, convergence and asymmetry.
Forwarding packets between networks by selecting the best available path from a route table.
- 08Firewalls
Zones, policy order and stateful inspection.
Policy enforcement points that permit or deny traffic between network zones based on connection state, identity and application context.
- 09Protocol & Port Reference
Consolidate with the searchable protocol reference.