Articles

HAProxy Basics: TCP and HTTP Modes and High Availability

Learn HAProxy essentials: TCP vs HTTP modes, config tips, health checks, and high availability patterns for resilient services.

Happy Eyeballs: Dual-Stack Connection Preference Explained

See how Happy Eyeballs picks IPv6 or IPv4 to speed dual-stack connections, what timers matter, and how to tune behavior.

Guest Wi-Fi vs Main Network: Isolation, VLANs, and Captive Portals

Set up safe guest Wi-Fi with isolation, VLANs, and captive portals. Learn best practices to protect your devices and bandwidth.

Flush DNS Cache on Windows, macOS, Linux, and Mobile

Clear DNS cache on Windows, macOS, Linux, iOS, and Android with exact commands and steps, plus when flushing actually helps.

EIGRP Explained: Features, Metrics, and When It Still Fits

Review EIGRP features and metrics, design tips, and when this protocol still fits compared to OSPF or BGP in modern networks.

EDNS Client Subnet: Geo-DNS, CDNs, and Privacy Trade-Offs

Understand EDNS Client Subnet, how CDNs use it for geo-routing, and the privacy trade-offs with ways to limit or disable exposure.

Dynamic DNS (DDNS): Keep a Stable Hostname at Home or Work

Keep a stable hostname for changing home or office IPs with DDNS. See providers, setup steps, and secure ways to expose services.

Dual-Stack vs IPv6-Only: Migration Paths and Trade-Offs

Compare dual-stack and IPv6-only designs, migration steps, costs, and trade-offs so you can plan a smooth, future-proof rollout.

Double NAT Problems: How to Detect and Fix Them Quickly

Detect double NAT fast and fix it with bridge mode, a DMZ, or proper routing so games, VPNs, and smart devices work reliably.

DoH vs DoT vs DNSSEC: Privacy and DNS Security Explained

Compare DoH, DoT, and DNSSEC for privacy and integrity. Understand what each solves, what it doesn’t, and when to combine them.

DNSSEC Basics: Signing Zones, DS Records, and Validation

Learn DNSSEC fundamentals: signing zones, DS chains, and validation. See benefits, risks, and how to deploy without breaking lookups.

DNS Records Explained: A, AAAA, CNAME, MX, TXT, NS, and SRV

A clear guide to A, AAAA, CNAME, MX, TXT, NS, and SRV records—what each does, common pitfalls, and examples you can copy and adapt.

DNS Propagation: How Long It Takes and How to Speed It Up

Find out how long DNS changes take worldwide, what factors affect it, and safe ways to speed it up and verify with reliable tools.

DNS over TLS: Setup Guides for Routers, Servers, and Clients

Set up DNS over TLS on routers, servers, and clients with step-by-step guides, test commands, and tips to avoid leaks and breakage.

DNS over HTTPS: How It Works and Where to Enable It Safely

Learn how DoH works, pros and cons, and where to enable it safely on browsers, routers, and devices without breaking parental controls.

DNS Caching: How It Speeds Browsing and When It Breaks Down

Understand how DNS caching speeds up browsing, what TTLs do, and how to fix stale records, cache poisoning, and hard-to-diagnose slowdowns.

DNS Amplification Attacks: What They Are and How to Stop Them

See how DNS amplification floods victims, why open resolvers matter, and the concrete steps to block, rate limit, and trace abuse.

DDoS Protection Basics: Rate Limits, ACLs, and Scrubbing

Learn core DDoS defenses: rate limits, ACLs, scrubbing centers, and upstream help—plus quick checks to spot attacks and keep sites online.

Common TCP and UDP Ports: Reference, Risks, and Use Cases

Browse a handy list of common TCP and UDP ports with meanings, defaults, risks, and security tips to harden services and close dangerous exposures.

CNAME vs A Records: Aliases, Canonical Names, and Pitfalls

Get clear on CNAME and A records, how aliases work, when to avoid CNAME at the apex, and common pitfalls that break resolution.

Cloudflare Spectrum, Argo, and WAF: What They Do for You

Explore Cloudflare Spectrum, Argo, and WAF in plain terms—what each service does, when to use it, and how they improve security and performance.

Check DNS Propagation Using Reliable, Free Online Tools

Quickly check global DNS propagation with trustworthy, free tools. See which records updated, spot caching issues, and know when it’s safe to switch.

CGNAT Explained: Why You Cannot Port Forward with Your ISP

Understand why CGNAT breaks inbound connections and port forwarding, what options you have, and when asking your ISP for a public IP makes sense.

Certificate Pinning: Benefits, Risks, and Best Practices

Learn what certificate pinning is, when it helps, when it hurts, and how to deploy safer alternatives without bricking your app.

CDN vs Reverse Proxy vs Load Balancer: What to Use When

Know when to use a CDN, a reverse proxy, or a load balancer. Compare use cases, benefits, limits, and common deployment patterns.

Carrier Routing Basics: Peering, Transit, and Public IXPs

Learn how networks connect: the difference between peering, transit, and public IXPs, who uses them, and how routes and costs are shaped.

Captive Portals: Guest Access, Walled Gardens, and Privacy

Understand how captive portals work, the pros and cons for guest access, what a walled garden allows, and how to protect users’ privacy.

CAA Records: Restrict Certificate Authorities for Your Domain

Find out what CAA records do, why they protect you from rogue certificates, and how to publish and test them without breaking existing issuance.

Bypass CGNAT Safely: IPv6, VPN Port Forwarding, and Tunnels

Stuck behind CGNAT? Learn safe ways around it using IPv6, VPN port forwarding, relays, and tunnels—plus the tradeoffs and risks to watch for.

Bufferbloat Explained: Fix Lag and Spikes on Home Networks

Understand bufferbloat, why your pings spike, and how to fix it with QoS, smart queue management, and better gear for smoother gaming and calls.

Botnets and Mirai: How IoT Devices Get Hijacked and Secured

See how botnets like Mirai recruit insecure IoT devices, what attacks they launch, and the practical steps you can take to harden and secure yours.

Block an IP Address on Your Router or Firewall: Step-by-Step

Follow this clear, step-by-step guide to block an IP on your router or firewall, with examples, safety tips, and ways to avoid locking out legitimate traffic.

BIND vs PowerDNS vs Knot DNS: Which Authoritative Server to Choose

Compare BIND, PowerDNS, and Knot DNS on speed, features, and operations. See real-world pros and cons to choose the right authoritative server for your needs.

BGP Route Leaks and Hijacks: What They Are and How to Monitor

Learn how BGP route leaks and hijacks happen, what they break, and how to detect them with RPKI and route monitors before customers feel the impact.

BGP Peering Setup: eBGP vs iBGP, Route Maps, and Filters

Step-by-step BGP peering guide. Differences between eBGP and iBGP, next-hop handling, route maps, prefix-lists, max-prefix, and filtering for stable networks.

BGP Fundamentals: AS Paths, Communities, MED, Local-Pref

Master BGP basics: sessions, route selection, AS-PATHs, communities, MED, LOCAL_PREF, and common policies. Includes labs, diagrams, and safe change practices.

ARP Spoofing and MITM: Detection, Prevention, and Response

How ARP spoofing works, signs to watch for, and tools to detect it. Practical defenses with static entries, DHCP snooping, DAI, VLAN design, and rapid response.

ARP Explained: Address Resolution Protocol for Beginners

Learn how ARP maps IPs to MACs, why caches matter, gratuitous ARP, and common issues like stale entries, duplicate IPs, and proxy ARP in simple, clear terms.

Anycast vs Unicast Routing: Performance and Resilience

Contrast Anycast and Unicast delivery. Compare latency, failover, cost, operational risks, so you can pick the right approach for web, DNS, and CDN workloads.

Anycast DNS: Setup Concepts, Benefits, and Common Gotchas

Plan and deploy Anycast DNS. Cover prefix design, health checks, routing policies, DDoS benefits, pitfalls like route flaps, uneven load, and path asymmetry.

ALPN Explained: HTTP/2, HTTP/3, and Protocol Negotiation

See how ALPN picks HTTP/2 or HTTP/3 over TLS. Learn client and server behaviors, cipher needs, and debugging steps for mismatches, fallbacks, and performance.

AAAA Records: When to Use IPv6 DNS and Troubleshooting Tips

What AAAA records are, when to publish IPv6 alongside A, and how to test, validate, and debug dual-stack DNS issues like Happy Eyeballs and misrouted prefixes.

802.1X for Wired and Wi-Fi: EAP Methods and Deployment Tips

Understand 802.1X for LAN and WLAN. Explore EAP methods, certificate setup, onboarding, and rollout tips to secure access without hurting productivity.

2.4 GHz vs 5 GHz vs 6 GHz Wi-Fi: Range, Speed, and Devices

Compare 2.4, 5, and 6 GHz Wi-Fi bands by range, speed, congestion, and device support. Learn when to choose each band for homes, offices, and mesh networks.

Find Your Router’s IP Address on Any Device in Minutes

Quick ways to find your router’s IP on Windows, macOS, Linux, iOS, and Android, plus what to do if the default gateway looks wrong.

Firewall Basics: Stateful vs Stateless and Next-Gen Firewalls

Get the essentials of stateful vs stateless filtering and next-gen firewalls, with examples that clarify rules, policies, and logging.

Firewall NAT Rules: SNAT vs DNAT with Real Examples

Understand SNAT vs DNAT with real examples, diagrams, and gotchas so services are reachable without breaking return traffic.

Fix “DNS Server Isn’t Responding” and Other DNS Errors Fast

Fix the “DNS server isn’t responding” error fast with step-by-step checks for resolvers, caches, firewalls, and ISP issues.

Fix IP Address Conflicts on Your Home or Office Network

Resolve IP conflicts quickly with DHCP hygiene, static mappings, and troubleshooting tips for Windows, macOS, and network gear.

IP Addresses: Why They Exist, How They Work, and What Comes After IPv4

Clear guide to IP addresses: what they do, IPv4 vs. IPv6, NAT, privacy basics, geolocation limits, and quick steps to check and troubleshoot your network.