Infrastructure pillar · Module 4 of 6

Networking basics

Networking can feel intimidating—there’s so much jargon. But at its core, it’s just about how computers talk to each other. Let’s demystify the basics.

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Controls stack visual kit

Reusable icons and a telemetry-to-audit diagram aligned to our fundamentals and operational guides.

Governance evidence

Use for control statements that cite ISO/IEC 42001 clause 6.3 change management, EU AI Act Articles 62–75, and SOC 2 trust service criteria.

Secure supply chain

Pair with SBOM, provenance, and intake guidance that references SPDX or CycloneDX formats, SLSA Level 3 attestations, and NIST SSDF tasks PS.3/PO.4.

Telemetry & evaluations

Highlight logging of prompts, responses, refusal rates, and safety filters alongside adversarial evaluation suites from NIST AI RMF playbooks or UK AISI guidance.

Assurance & resilience

Use for incident response and assurance artefacts that must meet OMB M-24-10 24-hour notifications, CIRCIA’s 72-hour clocks, and serious-incident duties under the EU AI Act.

Signals Controls Evidence Audit
  • Signals: prompt traces, supplier advisories, and safety filter activations streamed into monitoring.
  • Controls: guardrails, change review, SBOM validation, and access enforcement tied to AI lifecycle gates.
  • Evidence: runbooks that capture artefacts for ISO/IEC 42001 management reviews and SOC 2 narratives.
  • Audit: regulator-facing packets that satisfy EU AI Act post-market monitoring, OMB M-24-10, and CIRCIA timelines.

The concepts that actually matter

  • IP addresses. Every device on a network needs an address, just like houses need street addresses. IPv4 addresses look like 192.168.1.1. We’re running out of these, so IPv6 exists (longer, looks like 2001:0db8:85a3::8a2e), but IPv4 is still what you’ll encounter most.
  • DNS (Domain Name System). The internet’s phone book. You type google.com, DNS looks up the IP address so your computer knows where to go. When DNS breaks, the internet “goes down” even though everything’s actually fine.
  • Ports. If an IP address is a building’s street address, ports are apartment numbers. Web servers use port 80 (HTTP) and 443 (HTTPS). SSH uses 22. There are 65,535 possible ports.
  • Subnets. Dividing a network into smaller chunks. Like how a city has neighbourhoods. Devices in the same subnet can talk directly; crossing subnets requires a router.
  • DHCP. The thing that automatically gives your laptop an IP address when you connect to WiFi. Without it, you’d have to manually configure every device. (In the old days, we did. It was painful.)

The physical pieces

Inside your network

  • Switches: Connect devices in the same network. Like a smart power strip for network cables.
  • Routers: Connect different networks together. Every packet crossing the internet goes through many routers.
  • Access points: Provide WiFi. Just switches/routers with radios.

Protecting your network

  • Firewalls: Bouncers for network traffic. They decide what gets in and out based on rules you set.
  • VPNs: Encrypted tunnels through the internet. Use them to securely connect to your office network from home.
  • Load balancers: Spread traffic across multiple servers so no single one gets overwhelmed.

Common problems you’ll encounter

  • “Can’t connect to the internet.” First check: do you have an IP address? (ipconfig on Windows, ifconfig or ip addr on Mac/Linux). No IP often means DHCP isn’t working or you’re not really connected.
  • “Website won’t load.” Can you ping it? (ping google.com). If ping works but browser doesn’t, it’s probably DNS or a firewall issue.
  • “Everything is slow.” Network saturation (too much traffic), bad cables, or WiFi interference. Start by checking if wired connections have the same problem.

💡 The key insight

You don’t need to understand every protocol to be effective. Focus on the fundamentals—IP addressing, DNS, and basic troubleshooting. When you encounter something new, you’ll have the foundation to understand it.

Free resources to learn more

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