RFC References for Network Engineers

Essential networking RFCs every infrastructure engineer should know.

Request for Comments (RFC) documents define the protocols the internet runs on. This table collects the ones infrastructure engineers reference most: private and special-use addressing (RFC 1918, 6598, 5737), subnetting (RFC 4632), DNS (RFC 1035), DHCP (RFC 2131), NTP (RFC 5905), BGP (RFC 4271), syslog (RFC 5424), and the IPv6 addressing suite.

RFCTitleTopic
RFC 1918Address Allocation for Private InternetsPrivate IP ranges (10/8, 172.16/12, 192.168/16)
RFC 5737IPv4 Address Blocks Reserved for DocumentationDocumentation IPs (192.0.2/24, 198.51.100/24, 203.0.113/24)
RFC 6598IANA-Reserved IPv4 Prefix for Shared Address SpaceCGNAT range (100.64.0.0/10)
RFC 3927Dynamic Configuration of IPv4 Link-Local AddressesAPIPA / link-local (169.254.0.0/16)
RFC 4632Classless Inter-domain Routing (CIDR)CIDR notation and subnetting
RFC 952DoD Internet Host Table SpecificationOriginal hostname rules; updated by RFC 1123
RFC 1123Requirements for Internet HostsHost naming rules (alphanumeric + hyphen)
RFC 4291IPv6 Addressing ArchitectureIPv6 address formats, scopes, and special addresses
RFC 4193Unique Local IPv6 Unicast AddressesIPv6 ULA (fd00::/8)
RFC 4862IPv6 Stateless Address AutoconfigurationSLAAC
RFC 5424The Syslog ProtocolSyslog standard
RFC 1035Domain Names – Implementation and SpecificationDNS protocol
RFC 2131Dynamic Host Configuration ProtocolDHCP
RFC 5905Network Time Protocol Version 4NTPv4
RFC 4271A Border Gateway Protocol 4 (BGP-4)BGP standard

More Reference

Explore the other reference in the toolkit.

RFC 1918 Private IP Ranges
RFC 1918 defines the private IPv4 ranges 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16. See each range, host count, and common use.
Common TCP & UDP Ports
Reference list of common TCP and UDP ports: SSH, DNS, HTTP, HTTPS, SMTP, NTP, DHCP, SNMP, RDP, and more, with protocols and descriptions.
Fiber Connector Types
Reference guide to fiber optic connector types: LC, SC, ST, FC, MPO/MTP, and E2000 with polish, return loss, and typical use.
Ethernet Standards (IEEE 802.3)
Reference table of IEEE 802.3 Ethernet standards: 1000BASE-T, 10GBASE-T, 10GBASE-SR/LR, 25G, 40G, 100G, and 400G with media and distances.
Reserved & Special-Use IP Addresses
Reference table of special-use IPv4 ranges: loopback, link-local (APIPA), CGNAT, TEST-NET documentation ranges, multicast, and broadcast.
Cable Color Codes (TIA-606)
TIA-606 cable color codes for structured cabling: blue for horizontal cabling, orange for demarcation, purple for common equipment, and more.
Transceiver Form Factors
Reference table of optical transceiver form factors: SFP, SFP+, SFP28, QSFP+, QSFP28, QSFP-DD, CFP2, XFP, and CXP with speeds and distances.
WiFi Standards (IEEE 802.11)
Reference table of WiFi standards: 802.11b through 802.11be (Wi-Fi 1 to Wi-Fi 7) with maximum speeds, frequencies, and release years.
Power Connectors & Receptacles
Reference table of data center power connectors: NEMA 5-15P, L6-30P, IEC C13/C14, C19/C20, IEC 60309, Schuko, and BS 1363 with amp and voltage ratings.
Device Naming Conventions
Standard network device naming convention: use a <site>-<role>-<number> pattern. See examples for switches, firewalls, servers, and stack members.
Interface & Port Naming
How to standardize network interface names across vendors: Cisco IOS, Juniper Junos, and NX-OS/AOS-CX conventions with examples.
VLAN & Subnet Naming
Best practices for VLAN naming: descriptive names like SRV-PROD and GUEST-WIFI paired with documented VLAN IDs and subnets.