Network Reference
Quick-reference pages for the things you Google constantly. Bookmark them once and stop searching.
Private IP Ranges
RFC 1918, RFC 6598 (CGNAT), loopback, link-local, multicast — every reserved IPv4 block in one table.
Open →Default Router IP Addresses
Common default gateway IPs and login credentials by router brand.
Open →Common Network Ports
TCP and UDP port assignments for the protocols you actually encounter.
Open →DNS Record Types
A, AAAA, MX, TXT, CNAME, NS, SOA, SRV, CAA — what each one does.
Open →HTTP Status Codes
Every HTTP response code explained: 1xx through 5xx. When each is used, common causes.
Open →IPv6 Address Types
Loopback, link-local, ULA, multicast scopes, global unicast — the IPv6 address taxonomy.
Open →TLS Cipher Suites
Which ciphers are secure, which are deprecated, and what each component (kex, auth, sym, hash) means.
Open →SMTP Response Codes
250, 421, 550 and the rest — what your mail server's reply codes actually mean.
Open →Subnet Mask Table
Complete /0 through /32 lookup table: CIDR ↔ decimal mask ↔ host count ↔ wildcard.
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