IPv6 Link-Local Addresses (fe80::/10) Explained
IPv6 interfaces automatically use link-local addressing for essential neighbor and router discovery. Seeing fe80:: does not mean IPv6 is broken or globally reachable.
Technical Articles
NAT Loopback (Hairpin NAT) Explained for Home Servers
Hairpin NAT lets a client inside your LAN reach an internally hosted service using the same public hostname or public IP that outside users use.
MTU and MSS Explained: Why Some Sites Work While Large Transfers Fail
Maximum Transmission Unit and TCP Maximum Segment Size affect packet sizing. Misconfiguration can create partial connectivity that looks like DNS, VPN, or firewall trouble.
ARP Explained: How IPv4 Devices Find the MAC Address Behind a Local IP
ARP maps an IPv4 address to a link-layer address on the local network. Understanding it explains duplicate-IP warnings, gateway reachability, and many “same subnet but cannot connect” problems.
CGNAT and 100.64.0.0/10 Explained: Why Port Forwarding May Stop at the ISP
Carrier-grade NAT lets providers share public IPv4 addresses across customers. It changes what “my router WAN IP” means and can block unsolicited inbound connections.
Why 169.254.x.x Appears: IPv4 Link-Local (APIPA) Explained
A 169.254 address is usually a fallback local address selected when normal IPv4 configuration is unavailable. It is a clue about DHCP—not an internet gateway.
Access Point Mode vs. Router Mode vs. Bridge Mode
Know which device should route, which should only provide Wi-Fi, and how to avoid duplicate DHCP/NAT when adding a second networking device.
2.4 GHz vs. 5 GHz vs. 6 GHz Wi-Fi: Range, Speed, Congestion, and Compatibility
Choose the right Wi-Fi band by understanding propagation, available channels, client support, and why a faster band is not always better at distance.
DNS Explained: Resolver, Authoritative Server, A/AAAA, CNAME, MX, and Cache
Follow a domain lookup from your device to a resolver and authoritative DNS, then understand the records and caching involved.
NAT and Double NAT Explained for Home Networks
Understand private-to-public address translation, why two routers can cause double NAT, and when bridge or access-point mode is the right fix.