This is a list of the IP protocol numbers found in the field Protocol of the IPv4 header and the Next Header field of the IPv6 header. It is an identifier for the encapsulated protocol and determines the layout of the data that immediately follows the header. Both fields are eight bits wide. Protocol numbers are maintained and published by the Internet Assigned Numbers Authority (IANA).[1]

Hex Protocol Number Keyword Protocol References/RFC

0x00 0 HOPOPT IPv6 Hop-by-Hop Option RFC 8200

0x01 1 ICMP Internet Control Message Protocol RFC 792

0x02 2 IGMP Internet Group Management Protocol RFC 1112

0x03 3 GGP Gateway-to-Gateway Protocol RFC 823

0x04 4 IP-in-IP IP in IP (encapsulation) RFC 2003

0x05 5 ST Internet Stream Protocol RFC 1190, RFC 1819

0x06 6 TCP Transmission Control Protocol RFC 793

0x07 7 CBT Core-based trees RFC 2189

0x08 8 EGP Exterior Gateway Protocol RFC 888

0x09 9 IGP Interior Gateway Protocol (any private interior gateway, for example Cisco's IGRP)

0x0A 10 BBN-RCC-MON BBN RCC Monitoring

0x0B 11 NVP-II Network Voice Protocol RFC 741

0x0C 12 PUP Xerox PUP

0x0D 13 ARGUS ARGUS

0x0E 14 EMCON EMCON

0x0F 15 XNET Cross Net Debugger IEN 158[2]

0x10 16 CHAOS Chaos

0x11 17 UDP User Datagram Protocol RFC 768

0x12 18 MUX Multiplexing IEN 90[3]

0x13 19 DCN-MEAS DCN Measurement Subsystems

0x14 20 HMP Host Monitoring Protocol RFC 869

0x15 21 PRM Packet Radio Measurement

0x16 22 XNS-IDP XEROX NS IDP

0x17 23 TRUNK-1 Trunk-1

0x18 24 TRUNK-2 Trunk-2

0x19 25 LEAF-1 Leaf-1

0x1A 26 LEAF-2 Leaf-2

0x1B 27 RDP Reliable Data Protocol RFC 908

0x1C 28 IRTP Internet Reliable Transaction Protocol RFC 938

0x1D 29 ISO-TP4 ISO Transport Protocol Class 4 RFC 905

0x1E 30 NETBLT Bulk Data Transfer Protocol RFC 998

0x1F 31 MFE-NSP MFE Network Services Protocol

0x20 32 MERIT-INP MERIT Internodal Protocol

0x21 33 DCCP Datagram Congestion Control Protocol RFC 4340

0x22 34 3PC Third Party Connect Protocol

0x23 35 IDPR Inter-Domain Policy Routing Protocol RFC 1479

0x24 36 XTP Xpress Transport Protocol

0x25 37 DDP Datagram Delivery Protocol

0x26 38 IDPR-CMTP IDPR Control Message Transport Protocol

0x27 39 TP++ TP++ Transport Protocol

0x28 40 IL IL Transport Protocol

0x29 41 IPv6 IPv6 Encapsulation (6to4 and 6in4) RFC 2473

0x2A 42 SDRP Source Demand Routing Protocol RFC 1940

0x2B 43 IPv6-Route Routing Header for IPv6 RFC 8200

0x2C 44 IPv6-Frag Fragment Header for IPv6 RFC 8200

0x2D 45 IDRP Inter-Domain Routing Protocol

0x2E 46 RSVP Resource Reservation Protocol RFC 2205

0x2F 47 GRE Generic Routing Encapsulation RFC 2784, RFC 2890

0x30 48 DSR Dynamic Source Routing Protocol RFC 4728

0x31 49 BNA Burroughs Network Architecture

0x32 50 ESP Encapsulating Security Payload RFC 4303

0x33 51 AH Authentication Header RFC 4302

0x34 52 I-NLSP Integrated Net Layer Security Protocol TUBA

0x35 53 SwIPe SwIPe RFC 5237

0x36 54 NARP NBMA Address Resolution Protocol RFC 1735

0x37 55 MOBILE IP Mobility (Min Encap) RFC 2004

0x38 56 TLSP Transport Layer Security Protocol (using Kryptonet key management)

0x39 57 SKIP Simple Key-Management for Internet Protocol RFC 2356

0x3A 58 IPv6-ICMP ICMP for IPv6 RFC 4443, RFC 4884

0x3B 59 IPv6-NoNxt No Next Header for IPv6 RFC 8200

0x3C 60 IPv6-Opts Destination Options for IPv6 RFC 8200

0x3D 61 Any host internal protocol

0x3E 62 CFTP CFTP

0x3F 63 Any local network

0x40 64 SAT-EXPAK SATNET and Backroom EXPAK

0x41 65 KRYPTOLAN Kryptolan

0x42 66 RVD MIT Remote Virtual Disk Protocol

0x43 67 IPPC Internet Pluribus Packet Core

0x44 68 Any distributed file system

0x45 69 SAT-MON SATNET Monitoring

0x46 70 VISA VISA Protocol

0x47 71 IPCU Internet Packet Core Utility

0x48 72 CPNX Computer Protocol Network Executive

0x49 73 CPHB Computer Protocol Heart Beat

0x4A 74 WSN Wang Span Network

0x4B 75 PVP Packet Video Protocol

0x4C 76 BR-SAT-MON Backroom SATNET Monitoring

0x4D 77 SUN-ND SUN ND PROTOCOL-Temporary

0x4E 78 WB-MON WIDEBAND Monitoring

0x4F 79 WB-EXPAK WIDEBAND EXPAK

0x50 80 ISO-IP International Organization for Standardization Internet Protocol

0x51 81 VMTP Versatile Message Transaction Protocol RFC 1045

0x52 82 SECURE-VMTP Secure Versatile Message Transaction Protocol RFC 1045

0x53 83 VINES VINES

0x54 84 TTP TTP

0x54 84 IPTM Internet Protocol Traffic Manager

0x55 85 NSFNET-IGP NSFNET-IGP

0x56 86 DGP Dissimilar Gateway Protocol

0x57 87 TCF TCF

0x58 88 EIGRP EIGRP Informational RFC 7868

0x59 89 OSPF Open Shortest Path First RFC 2328

0x5A 90 Sprite-RPC Sprite RPC Protocol

0x5B 91 LARP Locus Address Resolution Protocol

0x5C 92 MTP Multicast Transport Protocol

0x5D 93 AX.25 AX.25

0x5E 94 OS KA9Q NOS compatible IP over IP tunneling

0x5F 95 MICP Mobile Internetworking Control Protocol

0x60 96 SCC-SP Semaphore Communications Sec. Pro

0x61 97 ETHERIP Ethernet-within-IP Encapsulation RFC 3378

0x62 98 ENCAP Encapsulation Header RFC 1241

0x63 99 Any private encryption scheme

0x64 100 GMTP GMTP

0x65 101 IFMP Ipsilon Flow Management Protocol

0x66 102 PNNI PNNI over IP

0x67 103 PIM Protocol Independent Multicast

0x68 104 ARIS IBM's ARIS (Aggregate Route IP Switching) Protocol

0x69 105 SCPS SCPS (Space Communications Protocol Standards) SCPS-TP[4]

0x6A 106 QNX QNX

0x6B 107 A/N Active Networks

0x6C 108 IPComp IP Payload Compression Protocol RFC 3173

0x6D 109 SNP Sitara Networks Protocol

0x6E 110 Compaq-Peer Compaq Peer Protocol

0x6F 111 IPX-in-IP IPX in IP

0x70 112 VRRP Virtual Router Redundancy Protocol, Common Address Redundancy Protocol (not IANA assigned) RFC 5798

0x71 113 PGM PGM Reliable Transport Protocol RFC 3208

0x72 114 Any 0-hop protocol

0x73 115 L2TP Layer Two Tunneling Protocol Version 3 RFC 3931

0x74 116 DDX D-II Data Exchange (DDX)

0x75 117 IATP Interactive Agent Transfer Protocol

0x76 118 STP Schedule Transfer Protocol

0x77 119 SRP SpectraLink Radio Protocol

0x78 120 UTI Universal Transport Interface Protocol

0x79 121 SMP Simple Message Protocol

0x7A 122 SM Simple Multicast Protocol draft-perlman-simple-multicast-03

0x7B 123 PTP Performance Transparency Protocol

0x7C 124 IS-IS over IPv4 Intermediate System to Intermediate System (IS-IS) Protocol over IPv4 RFC 1142 and RFC 1195

0x7D 125 FIRE Flexible Intra-AS Routing Environment

0x7E 126 CRTP Combat Radio Transport Protocol

0x7F 127 CRUDP Combat Radio User Datagram

0x80 128 SSCOPMCE Service-Specific Connection-Oriented Protocol in a Multilink and Connectionless Environment ITU-T Q.2111 (1999)

0x81 129 IPLT

0x82 130 SPS Secure Packet Shield

0x83 131 PIPE Private IP Encapsulation within IP Expired I-D draft-petri-mobileip-pipe-00.txt

0x84 132 SCTP Stream Control Transmission Protocol RFC 4960

0x85 133 FC Fibre Channel

0x86 134 RSVP-E2E-IGNORE Reservation Protocol (RSVP) End-to-End Ignore RFC 3175

0x87 135 Mobility Header Mobility Extension Header for IPv6 RFC 6275

0x88 136 UDPLite Lightweight User Datagram Protocol RFC 3828

0x89 137 MPLS-in-IP Multiprotocol Label Switching Encapsulated in IP RFC 4023, RFC 5332

0x8A 138 manet MANET Protocols RFC 5498

0x8B 139 HIP Host Identity Protocol RFC 5201

0x8C 140 Shim6 Site Multihoming by IPv6 Intermediation RFC 5533

0x8D 141 WESP Wrapped Encapsulating Security Payload RFC 5840

0x8E 142 ROHC Robust Header Compression RFC 5856

0x8F 143 Ethernet Segment Routing over IPv6 RFC 8986

0x90 144 AGGFRAG AGGFRAG Encapsulation Payload for ESP RFC 9347

0x91 145 NSH Network Service Header draft-ietf-spring-nsh-sr

0x92-0xFC 146-252 Unassigned

0xFD-0xFE 253-254 Use for experimentation and testing RFC 3692

0xFF 255 Reserved