IANA Internet Standards¶

The Internet Assigned Numbers Authority (IANA) maintains the registries and protocol parameters that define the operational standards of the internet. This page documents the key standards at every layer of the network stack, from physical addressing to application protocols.

Overview¶

Standards Organizations¶

flowchart TD
    subgraph "Application"
        A1["HTTP/HTTPS<br/>Port 80/443"]
        A2["DNS<br/>Port 53"]
        A3["SMTP<br/>Port 25/587"]
    end
    subgraph "Transport"
        T1["TCP<br/>RFC 793"]
        T2["UDP<br/>RFC 768"]
    end
    subgraph "Network"
        N1["IPv4<br/>RFC 791"]
        N2["IPv6<br/>RFC 8200"]
        N3["ICMP<br/>RFC 792"]
    end
    subgraph "Data Link"
        D1["Ethernet<br/>802.3"]
        D2["Wi-Fi<br/>802.11"]
        D3["VLAN<br/>802.1Q"]
    end
    subgraph "Physical"
        P1["Cat 6a UTP"]
        P2["Fiber<br/>Single/Multi-mode"]
        P3["Radio<br/>2.4/5/6 GHz"]
    end

    A1 --> T1
    A2 --> T2
    T1 --> N1
    T2 --> N1
    N1 --> D1
    D1 --> P1
    D2 --> P3

    style A1 fill:#4a7c59,color:#fff
    style N1 fill:#2d5a3a,color:#fff
    style P1 fill:#5a3a2d,color:#fff

Layer 1 — Physical¶

Ethernet (IEEE 802.3)¶

Wi-Fi (IEEE 802.11)¶

Layer 2 — Data Link¶

MAC Address Format¶

48-bit MAC address: XX-XX-XX-XX-XX-XX
  |-- OUI --| |-- NIC --|

OUI (Organizationally Unique Identifier): 24 bits, assigned by IEEE
NIC (Network Interface Controller): 24 bits, assigned by manufacturer

Example: 00-50-56-C0-00-08
  00-50-56 = VMware, Inc.
  C0-00-08 = Specific virtual NIC

Ethernet Frame Structure¶

Preamble (7 bytes) + SFD (1 byte) + Destination MAC (6) + Source MAC (6) + 802.1Q Tag (4, optional) + EtherType (2) + Payload (46-1500) + FCS (4)

EtherType values (IANA assigned):
  0x0800 = IPv4
  0x0806 = ARP
  0x86DD = IPv6
  0x8100 = 802.1Q VLAN
  0x8847 = MPLS
  0x8863/0x8864 = PPPoE
  0x888E = 802.1X EAPOL
  0x88CC = LLDP

VLAN (IEEE 802.1Q)¶

Reserved VLAN IDs: 0 (null), 1 (default), 4095 (reserved)

Layer 3 — Network¶

IPv4 Address Classes (Historical)¶

RFC 1918 Private Address Space¶

IPv6 Address Types¶

Type	Prefix	Example
Global Unicast	2000::/3	2001:db8::1
Unique Local	fc00::/7	fd00:1
Link-Local	fe80::/10	fe80::1%eth0
Multicast	ff00::/8	ff02::1
Loopback	::1/128	::1
Unspecified	::/128	::
IPv4-mapped	::ffff:0:0/96	::ffff:192.0.2.1

IP Protocol Numbers¶

Layer 4 — Transport¶

IANA Port Number Ranges¶

Well-Known Port Assignments¶

TCP Header Flags¶

Layer 5-7 — Session, Presentation, Application¶

HTTP Status Codes (IANA Registered)¶

MIME Types (IANA Media Types)¶

DNS Resource Record Types¶

Related Deep Hole¶

• IANA Protocol Registries — Master registry index
• IANA Service Name and Port Number Registry — Port assignments
• IANA MIME Media Types — Media type registry
• IANA DNS Parameters — DNS record types
• IANA IPv6 Special-Purpose Address Registry — IPv6 special addresses
• IEEE 802 Standards — LAN/MAN standards
• IETF RFC Index — Complete RFC listing