| Protocol Number | Common Name | Protocol - Long Name | References |
| 0 | HOPOPT | IPv6 Hop-by-Hop Option | [RFC1883] |
| 1 | ICMP | Internet Control Message | [RFC792] |
| 2 | IGMP | Internet Group Management | [RFC1112] |
| 3 | GGP | Gateway-to-Gateway | [RFC823] |
| 4 | IP | IP in IP (encapsulation) | [RFC2003] |
| 5 | ST | Stream | [RFC1190][RFC1819] |
| 6 | TCP | Transmission Control | [RFC793] |
| 7 | CBT | CBT | [Ballardie] |
| 8 | EGP | Exterior Gateway Protocol | [RFC888][DLM1] |
| 9 | IGP | any private interior gateway | [IANA] |
| (used by Cisco for their IGRP) | |||
| 10 | BBN-RCC-MON | BBN RCC Monitoring | [SGC] |
| 11 | NVP-II | Network Voice Protocol | [RFC741,SC3] |
| 12 | PUP | PUP | [PUP,XEROX] |
| 13 | ARGUS | ARGUS | [RWS4] |
| 14 | EMCON | EMCON | [BN7] |
| 15 | XNET | Cross Net Debugger | [IEN158,JFH2] |
| 16 | CHAOS | Chaos | [NC3] |
| 17 | UDP | User Datagram | [RFC768,JBP] |
| 18 | MUX | Multiplexing | [IEN90,JBP] |
| 19 | DCN-MEAS | DCN Measurement Subsystems | [DLM1] |
| 20 | HMP | Host Monitoring | [RFC869,RH6] |
| 21 | PRM | Packet Radio Measurement | [ZSU] |
| 22 | XNS-IDP | XEROX NS IDP | [ETHERNET,XEROX] |
| 23 | TRUNK-1 | Trunk-1 | [BWB6] |
| 24 | TRUNK-2 | Trunk-2 | [BWB6] |
| 25 | LEAF-1 | Leaf-1 | [BWB6] |
| 26 | LEAF-2 | Leaf-2 | [BWB6] |
| 27 | RDP | Reliable Data Protocol | [RFC908,RH6] |
| 28 | IRTP | Internet Reliable Transaction | [RFC938,TXM] |
| 29 | ISO-TP4 | ISO Transport Protocol Class 4 | [RFC905,RC77] |
| 30 | NETBLT | Bulk Data Transfer Protocol | [RFC969,DDC1] |
| 31 | MFE-NSP | MFE Network Services Protocol | [MFENET,BCH2] |
| 32 | MERIT-INP | MERIT Internodal Protocol | [HWB] |
| 33 | DCCP | Datagram Congestion Control Protocol | [RFC4340] |
| 34 | 3PC | Third Party Connect Protocol | [SAF3] |
| 35 | IDPR | Inter-Domain Policy Routing Protocol | [MXS1] |
| 36 | XTP | XTP | [GXC] |
| 37 | DDP | Datagram Delivery Protocol | [WXC] |
| 38 | IDPR-CMTP | IDPR Control Message Transport Proto | [MXS1] |
| 39 | TP++ | TP++ Transport Protocol | [DXF] |
| 40 | IL | IL Transport Protocol | [Presotto] |
| 41 | IPv6 | Ipv6 | [Deering] |
| 42 | SDRP | Source Demand Routing Protocol | [DXE1] |
| 43 | IPv6-Route | Routing Header for IPv6 | [Deering] |
| 44 | IPv6-Frag | Fragment Header for IPv6 | [Deering] |
| 45 | IDRP | Inter-Domain Routing Protocol | [Sue Hares] |
| 46 | RSVP | Reservation Protocol | [Bob Braden] |
| 47 | GRE | General Routing Encapsulation | [Tony Li] |
| 48 | DSR | Dynamic Source Routing Protocol | [RFC4728] |
| 49 | BNA | BNA | [Gary Salamon] |
| 50 | ESP | Encap Security Payload | [RFC2406] |
| 51 | AH | Authentication Header | [RFC2402] |
| 52 | I-NLSP | Integrated Net Layer Security TUBA | [GLENN] |
| 53 | SWIPE | IP with Encryption | [JI6] |
| 54 | NARP | NBMA Address Resolution Protocol | [RFC1735] |
| 55 | MOBILE | IP Mobility | [Perkins] |
| 56 | TLSP | Transport Layer Security Protocol | [Oberg] |
| using Kryptonet key management | |||
| 57 | SKIP | SKIP | [Markson] |
| 58 | IPv6-ICMP | ICMP for IPv6 | [RFC1883] |
| 59 | IPv6-NoNxt | No Next Header for IPv6 | [RFC1883] |
| 60 | IPv6-Opts | Destination Options for IPv6 | [RFC1883] |
| 61 | any host internal protocol | [IANA] | |
| 62 | CFTP | CFTP | [CFTP,HCF2] |
| 63 | any local network | [IANA] | |
| 64 | SAT-EXPAK | SATNET and Backroom EXPAK | [SHB] |
| 65 | KRYPTOLAN | Kryptolan | [PXL1] |
| 66 | RVD | MIT Remote Virtual Disk Protocol | [MBG] |
| 67 | IPPC | Internet Pluribus Packet Core | [SHB] |
| 68 | any distributed file system | [IANA] | |
| 69 | SAT-MON | SATNET Monitoring | [SHB] |
| 70 | VISA | VISA Protocol | [GXT1] |
| 71 | IPCV | Internet Packet Core Utility | [SHB] |
| 72 | CPNX | Computer Protocol Network Executive | [DXM2] |
| 73 | CPHB | Computer Protocol Heart Beat | [DXM2] |
| 74 | WSN | Wang Span Network | [VXD] |
| 75 | PVP | Packet Video Protocol | [SC3] |
| 76 | BR-SAT-MON | Backroom SATNET Monitoring | [SHB] |
| 77 | SUN-ND | SUN ND PROTOCOL-Temporary | [WM3] |
| 78 | WB-MON | WIDEBAND Monitoring | [SHB] |
| 79 | WB-EXPAK | WIDEBAND EXPAK | [SHB] |
| 80 | ISO-IP | ISO Internet Protocol | [MTR] |
| 81 | VMTP | VMTP | [DRC3] |
| 82 | SECURE-VMTP | SECURE-VMTP | [DRC3] |
| 83 | VINES | VINES | [BXH] |
| 84 | TTP | TTP | [JXS] |
| 85 | NSFNET-IGP | NSFNET-IGP | [HWB] |
| 86 | DGP | Dissimilar Gateway Protocol | [DGP,ML109] |
| 87 | TCF | TCF | [GAL5] |
| 88 | EIGRP | EIGRP | [CISCO,GXS] |
| 89 | OSPFIGP | OSPFIGP | [RFC1583,JTM4] |
| 90 | Sprite-RPC | Sprite RPC Protocol | [SPRITE,BXW] |
| 91 | LARP | Locus Address Resolution Protocol | [BXH] |
| 92 | MTP | Multicast Transport Protocol | [SXA] |
| 93 | AX.25 | AX.25 Frames | [BK29] |
| 94 | IPIP | IP-within-IP Encapsulation Protocol | [JI6] |
| 95 | MICP | Mobile Internetworking Control Pro. | [JI6] |
| 96 | SCC-SP | Semaphore Communications Sec. Pro. | [HXH] |
| 97 | ETHERIP | Ethernet-within-IP Encapsulation | [RFC3378] |
| 98 | ENCAP | Encapsulation Header | [RFC1241,RXB3] |
| 99 | any private encryption scheme | [IANA] | |
| 100 | GMTP | GMTP | [RXB5] |
| 101 | IFMP | Ipsilon Flow Management Protocol | [Hinden] |
| 102 | PNNI | PNNI over IP | [Callon] |
| 103 | PIM | Protocol Independent Multicast | [Farinacci] |
| 104 | ARIS | ARIS | [Feldman] |
| 105 | SCPS | SCPS | [Durst] |
| 106 | QNX | QNX | [Hunter] |
| 107 | A/N | Active Networks | [Braden] |
| 108 | IPComp | IP Payload Compression Protocol | [RFC2393] |
| 109 | SNP | Sitara Networks Protocol | [Sridhar] |
| 110 | Compaq-Peer | Compaq Peer Protocol | [Volpe] |
| 111 | IPX-in-IP | IPX in IP | [Lee] |
| 112 | VRRP | Virtual Router Redundancy Protocol | [RFC3768] |
| 113 | PGM | PGM Reliable Transport Protocol | [Speakman] |
| 114 | any 0-hop protocol | [IANA] | |
| 115 | L2TP | Layer Two Tunneling Protocol | [Aboba] |
| 116 | DDX | D-II Data Exchange (DDX) | [Worley] |
| 117 | IATP | Interactive Agent Transfer Protocol | [Murphy] |
| 118 | STP | Schedule Transfer Protocol | [JMP] |
| 119 | SRP | SpectraLink Radio Protocol | [Hamilton] |
| 120 | UTI | UTI | [Lothberg] |
| 121 | SMP | Simple Message Protocol | [Ekblad] |
| 122 | SM | SM | [Crowcroft] |
| 123 | PTP | Performance Transparency Protocol | [Welzl] |
| 124 | ISIS over IP | v4 | [Przygienda] |
| 125 | FIRE | [Partridge] | |
| 126 | CRTP | Combat Radio Transport Protocol | [Sautter] |
| 127 | CRUDP | Combat Radio User Datagram | [Sautter] |
| 128 | SSCOPMCE | [Waber] | |
| 129 | IPLT | [Hollbach] | |
| 130 | SPS | Secure Packet Shield | [McIntosh] |
| 131 | PIPE | Private IP Encapsulation within IP | [Petri] |
| 132 | SCTP | Stream Control Transmission Protocol | [Stewart] |
| 133 | FC | Fibre Channel | [Rajagopal] |
| 134 | RSVP-E2E-IGN | ORE | [RFC3175] |
| 135 | Mobility Hea | der | [RFC3775] |
| 136 | UDPLite | [RFC3828] | |
| 137 | MPLS-in-IP | [RFC4023] | |
| 138 | manet | MANET Protocols | [RFC-ietf-manet-iana-07.txt] |
| 139 | HIP | Host Identity Protocol | [RFC-ietf-hip-base-10.txt] |
| 140-252 | Unassigned | [IANA] | |
| 253 | Use for expe | rimentation and testing | [RFC3692] |
| 254 | Use for expe | rimentation and testing | [RFC3692] |
| 255 | Reserved | [IANA] |