Link-Layer Types for PCAP-related Capture File Formats
draft-ietf-opsawg-pcaplinktype-16
| Document | Type | Active Internet-Draft (opsawg WG) | |
|---|---|---|---|
| Authors | Guy Harris , Michael Richardson | ||
| Last updated | 2026-01-13 (Latest revision 2025-12-04) | ||
| Replaces | draft-richardson-opsawg-pcaplinktype | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | Informational | ||
| Formats | |||
| Reviews | |||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | Submitted to IESG for Publication | |
| Associated WG milestone |
|
||
| Document shepherd | Joe Clarke | ||
| Shepherd write-up | Show Last changed 2025-04-25 | ||
| IESG | IESG state | IESG Evaluation::Revised I-D Needed | |
| Action Holders | |||
| Consensus boilerplate | Yes | ||
| Telechat date |
(None)
Has enough positions to pass. |
||
| Responsible AD | Mahesh Jethanandani | ||
| Send notices to | jclarke@cisco.com | ||
| IANA | IANA review state | Version Changed - Review Needed |
draft-ietf-opsawg-pcaplinktype-16
Network Working Group G. Harris, Ed.
Internet-Draft
Intended status: Informational M. Richardson
Expires: 7 June 2026 Sandelman
4 December 2025
Link-Layer Types for PCAP-related Capture File Formats
draft-ietf-opsawg-pcaplinktype-16
Abstract
This document describes a set of Packet CAPture (PCAP)-related
LinkType values and creates an IANA registry for those values. These
values are used by the PCAP and PCAP-Now-Generic specifications.
About This Document
This note is to be removed before publishing as an RFC.
Status information for this document may be found at
https://datatracker.ietf.org/doc/draft-ietf-opsawg-pcaplinktype/.
Discussion of this document takes place on the opsawg Working Group
mailing list (mailto:opsawg@ietf.org), which is archived at
https://mailarchive.ietf.org/arch/browse/opsawg/. Subscribe at
https://www.ietf.org/mailman/listinfo/opsawg/.
Source for this draft and an issue tracker can be found at
https://github.com/IETF-OPSAWG-WG/pcapng.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 7 June 2026.
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Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3
2.1. PCAP Registry . . . . . . . . . . . . . . . . . . . . . . 3
2.2. LinkType Registry . . . . . . . . . . . . . . . . . . . . 3
2.2.1. Initial Values . . . . . . . . . . . . . . . . . . . 4
2.2.2. Guidance for Designated Experts . . . . . . . . . . . 25
3. Security Considerations . . . . . . . . . . . . . . . . . . . 26
4. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 26
5. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 26
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
6.1. Normative References . . . . . . . . . . . . . . . . . . 26
6.2. Informative References . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 38
1. Introduction
In the late 1980s, Van Jacobson, Steve McCanne, and others at the
Network Research Group at Lawrence Berkeley National Laboratory
developed the tcpdump program to capture and dissect network traces.
The code to capture traffic, using low-level mechanisms in various
operating systems, and to read and write network traces to a file was
later put into a library named libpcap [LIBPCAP].
Other documents describe the original (legacy) file format used by
tcpdump (PCAP, [I-D.ietf-opsawg-pcap]), as well as a revised file
format [I-D.ietf-opsawg-pcapng], both of which are used by tcpdump
and Wireshark [Wireshark].
Within those file formats each packet that is captured is indicated
by a LinkType value. The LinkType value selects one of many hundred
formats for metadata and Layer 2 encapsulation of the packet.
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This document creates an IANA registry for LinkType values,
establishing the IANA Considerations by which other uses of the PCAP-
related formats may register new LinkType values.
2. IANA Considerations
2.1. PCAP Registry
IANA is requested to create a new registry group entitled "The PCAP
Registry".
2.2. LinkType Registry
IANA is also requested to create a registry entitled "PCAP-related
LinkType List" under The PCAP registry group (Section 2.1).
The registry has the following structure:
* LinkType Value: Indicates the 16-bit unsigned integer assigned for
this LinkType.
* LinkType Name: Indicates the symbolic name for this LinkType. The
name is prefixed with "LINKTYPE_" (i.e., LINKTYPE_something).
* Change Controller: who to accept changes from
* Description: Provides a very short description.
* Reference: Indicates an authoritative document reference for the
LinkType or a requester reference.
The policy allocation for the LinkType values is as follows:
* Values from 0 to 65000 are allocated following an Expert Review
policy (Section 4.5 of [RFC8126]). Values in the ranges 0-10,
50-51, and 98-301 are already assigned; values in the ranges 11-49
and 52-97 are reserved and must not be assigned.
* Values from 65001 to 65535 are reserved for Experimental Use
(Section 4.2 of [RFC8126]).
The initial version of the registry is provided in Section 2.2.1. In
each case here, the reference should be set to [TCPDUMP] and the RFC
number to be assigned to this document, which is not repeated each
time.
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The initial contents of the table are based upon the link-layer
header type list maintained by libpcap, and published on [TCPDUMP].
The change controller for all initial entries that have no other
reference is linktype@tcpdump.org.
LinkType values 147 to 162 named LINKTYPE_RESERVED_xx were originally
reserved for Experimental/Private Use, and that use continues to be
supported. However, new private use cases should use the values in
the 65001-65535 range.
In general, Experimental Use values should never leak out of the
entity that uses it. As the FCFS range is large and easily obtained,
official values are recommended.
There is often an associated Data Link Type (DLT) value which is
often identical in value, but not universally so. DLT values are
associated with specific operating systems, and the numerical
values for some of them are operating system specific, and are
thus not subject to standardization.
2.2.1. Initial Values
This is the initial table for the registry:
Name LINKTYPE_NULL
Number 0
Description BSD loopback encapsulation
Reference [LINKTYPE_NULL]
Name LINKTYPE_ETHERNET
Number 1
Description IEEE 802.3 Ethernet
Reference: [LINKTYPE_ETHERNET]
Name LINKTYPE_EXP_ETHERNET
Number 2
Description Xerox experimental 3Mb Ethernet
Reference [PracConsEthDesign]
Name LINKTYPE_AX25
Number 3
Description AX.25 layer 2 packets
Reference [LINKTYPE_AX25]
Name LINKTYPE_PRONET
Number 4
Description Proteon PRONet Token Ring
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Name LINKTYPE_CHAOS
Number 5
Description MIT Chaosnet
Reference [AIM-628]
Name LINKTYPE_IEEE802_5
Number 6
Description IEEE 802.5 Token Ring
Name LINKTYPE_ARCNET_BSD
Number 7
Description ARCNET Data Packets with BSD encapsulation
Name LINKTYPE_SLIP
Number 8
Description SLIP, with a direction header
Reference [LINKTYPE_SLIP]
Name LINKTYPE_PPP
Number 9
Description PPP
Reference [LINKTYPE_PPP]
Name LINKTYPE_FDDI
Number 10
Description FDDI: per ANSI INCITS 239-1994
Name Not available for assignment
Number 11-49
Description Do not use these values
Name LINKTYPE_PPP_HDLC
Number 50
Description PPP in HDLC-like framing
Reference [LINKTYPE_PPP_HDLC]
Name LINKTYPE_PPP_ETHER
Number 51
Description PPPoE session packets
Reference [LINKTYPE_PPP_ETHER]
Name Not available for assignment
Number 52-98
Description Used historically by NetBSD
Name LINKTYPE_SYMANTEC_FIREWALL
Number 99
Description Symantec Enterprise Firewall
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Name LINKTYPE_ATM_RFC1483
Number 100
Description LLC/SNAP-encapsulated ATM
Reference [LINKTYPE_ATM_RFC1483]
Name LINKTYPE_RAW
Number 101
Description IP without link-layer headers
Reference [LINKTYPE_RAW] [RFC791] [RFC8200]
Name LINKTYPE_SLIP_BSDOS
Number 102
Description BSD/OS SLIP BPF header
Name LINKTYPE_PPP_BSDOS
Number 103
Description BSD/OS PPP BPF header
Name LINKTYPE_C_HDLC
Number 104
Description Cisco PPP with HDLC framing
Reference [LINKTYPE_C_HDLC]
Name LINKTYPE_IEEE802_11
Number 105
Description IEEE 802.11 wireless LAN
Name LINKTYPE_ATM_CLIP
Number 106
Description ATM Classical IP, with no header preceding IP
Name LINKTYPE_FRELAY
Number 107
Description Frame Relay LAPF
Reference [LINKTYPE_FRELAY]
Name LINKTYPE_LOOP
Number 108
Description OpenBSD loopback encapsulation
Reference [LINKTYPE_LOOP]
Name LINKTYPE_ENC
Number 109
Description OpenBSD IPsec encapsulation
Name LINKTYPE_LANE8023
Number 110
Description ATM LANE + 802.3
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Name LINKTYPE_HIPPI
Number 111
Description NetBSD HIPPI
Name LINKTYPE_HDLC
Number 112
Description NetBSD HDLC framing
Name LINKTYPE_LINUX_SLL
Number 113
Description Linux "cooked" capture encapsulation
Reference [LINKTYPE_LINUX_SLL]
Name LINKTYPE_LTALK
Number 114
Description Apple LocalTalk
Reference [LINKTYPE_LTALK]
Name LINKTYPE_ECONET
Number 115
Description Acorn Econet
Name LINKTYPE_IPFILTER
Number 116
Description OpenBSD ipfilter
Name LINKTYPE_PFLOG
Number 117
Description PF packet filter logging
Name LINKTYPE_CISCO_IOS
Number 118
Description Cisco-internal use
Name LINKTYPE_IEEE802_11_PRISM
Number 119
Description IEEE 802.11 wireless LAN, preceded by a Prism monitor
mode header
Reference [LINKTYPE_IEEE802_11_PRISM]
Name LINKTYPE_IEEE802_11_AIRONET
Number 120
Description 802.11 + FreeBSD Aironet radio metadata
Name LINKTYPE_HHDLC
Number 121
Description Siemens HiPath HDLC
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Name LINKTYPE_IP_OVER_FC
Number 122
Description IP and ATM over Fibre Channel
Reference [LINKTYPE_IP_OVER_FC]
Name LINKTYPE_SUNATM
Number 123
Description ATM traffic captured from a SunATM device
Reference [LINKTYPE_SUNATM]
Name LINKTYPE_RIO
Number 124
Description RapidIO
Name LINKTYPE_PCI_EXP
Number 125
Description PCI Express
Name LINKTYPE_AURORA
Number 126
Description Xilinx Aurora link layer
Name LINKTYPE_IEEE802_11_RADIOTAP
Number 127
Description IEEE 802.11 wireless LAN, preceded by a Radiotap header
Reference [Radiotap]
Name LINKTYPE_TZSP
Number 128
Description Tazmen Sniffer Protocol
Name LINKTYPE_ARCNET_LINUX
Number 129
Description ARCNET Data Packets with Linux encapsulation
Name LINKTYPE_JUNIPER_MLPPP
Number 130
Description Juniper Networks
Name LINKTYPE_JUNIPER_MLFR
Number 131
Description Juniper Networks
Name LINKTYPE_JUNIPER_ES
Number 132
Description Juniper Networks
Name LINKTYPE_JUNIPER_GGSN
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Number 133
Description Juniper Networks
Name LINKTYPE_JUNIPER_MFR
Number 134
Description Juniper Networks
Name LINKTYPE_JUNIPER_ATM2
Number 135
Description Juniper Networks
Name LINKTYPE_JUNIPER_SERVICES
Number 136
Description Juniper Networks
Name LINKTYPE_JUNIPER_ATM1
Number 137
Description Juniper Networks
Name LINKTYPE_APPLE_IP_OVER_IEEE1394
Number 138
Description Apple IP-over-IEEE 1394 cooked header
Reference [LINKTYPE_APPLE_IP_OVER_IEEE1394]
Name LINKTYPE_MTP2_WITH_PHDR
Number 139
Description SS7 MTP2 frames, with a pseudo-header
Reference [LINKTYPE_MTP2_WITH_PHDR]
Name LINKTYPE_MTP2
Number 140
Description SS7 MTP2 packets
Reference [LINKTYPE_MTP2]
Name LINKTYPE_MTP3
Number 141
Description SS7 MTP3 packets
Reference [LINKTYPE_MTP3]
Name LINKTYPE_SCCP
Number 142
Description SS7 SCCP packets
Reference [LINKTYPE_SCCP]
Name LINKTYPE_DOCSIS
Number 143
Description DOCSIS MAC frames
Reference [DOCSIS-4.0-MULP]
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Name LINKTYPE_LINUX_IRDA
Number 144
Description Linux-IrDA packets
Reference [LINKTYPE_LINUX_IRDA]
Name LINKTYPE_IBM_SP
Number 145
Description IBM SP switch
Name LINKTYPE_IBM_SN
Number 146
Description IBM Next Federation switch
Name LINKTYPE_RESERVED_01
Number 147
Description For private use (deprecated)
Name LINKTYPE_RESERVED_02
Number 148
Description For private use (deprecated)
Name LINKTYPE_RESERVED_03
Number 149
Description For private use (deprecated)
Name LINKTYPE_RESERVED_04
Number 150
Description For private use (deprecated)
Name LINKTYPE_RESERVED_05
Number 151
Description For private use (deprecated)
Name LINKTYPE_RESERVED_06
Number 152
Description For private use (deprecated)
Name LINKTYPE_RESERVED_07
Number 153
Description For private use (deprecated)
Name LINKTYPE_RESERVED_08
Number 154
Description For private use (deprecated)
Name LINKTYPE_RESERVED_09
Number 155
Description For private use (deprecated)
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Name LINKTYPE_RESERVED_10
Number 156
Description For private use (deprecated)
Name LINKTYPE_RESERVED_11
Number 157
Description For private use (deprecated)
Name LINKTYPE_RESERVED_12
Number 158
Description For private use (deprecated)
Name LINKTYPE_RESERVED_13
Number 159
Description For private use (deprecated)
Name LINKTYPE_RESERVED_14
Number 160
Description For private use (deprecated)
Name LINKTYPE_RESERVED_15
Number 161
Description For private use (deprecated)
Name LINKTYPE_RESERVED_16
Number 162
Description For private use (deprecated)
Name LINKTYPE_IEEE802_11_AVS
Number 163
Description IEEE 802.11 wireless LAN, preceded by an AVS header
Reference [AVS]
Name LINKTYPE_JUNIPER_MONITOR
Number 164
Description Juniper Networks
Name LINKTYPE_BACNET_MS_TP
Number 165
Description BACnet MS/TP frames
Reference [LINKTYPE_BACNET_MS_TP]
Name LINKTYPE_PPP_PPPD
Number 166
Description PPP preceded by a direction octet and an HDLC-like
control field
Reference [LINKTYPE_PPP_PPPD]
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Name LINKTYPE_JUNIPER_PPPOE
Number 167
Description Juniper Networks
Name LINKTYPE_JUNIPER_PPPOE_ATM
Number 168
Description Juniper Networks
Name LINKTYPE_GPRS_LLC
Number 169
Description General Packet Radio Service Logical Link Control, as
per 3GPP TS 04.64
Reference [_3GPP-TS-04.64]
Name LINKTYPE_GPF_T
Number 170
Description Transparent-mapped generic framing procedure
Reference [G.7041]
Name LINKTYPE_GPF_F
Number 171
Description Frame-mapped generic framing procedure
Reference [G.7041]
Name LINKTYPE_GCOM_T1E1
Number 172
Description Gcom T1/E1 line monitoring equipment
Name LINKTYPE_GCOM_SERIAL
Number 173
Description Gcom T1/E1 line monitoring equipment
Name LINKTYPE_JUNIPER_PIC_PEER
Number 174
Description Juniper Networks
Name LINKTYPE_ERF_ETH
Number 175
Description Endace TYPE_ETH ERF records
Reference [LINKTYPE_ERF]
Name LINKTYPE_ERF_POS
Number 176
Description Endace TYPE_POS_HDLC ERF records
Reference [LINKTYPE_ERF]
Name LINKTYPE_LINUX_LAPD
Number 177
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Description Linux vISDN LAPD frames
Reference [LINKTYPE_LINUX_LAPD]
Name LINKTYPE_JUNIPER_ETHER
Number 178
Description Juniper Networks
Name LINKTYPE_JUNIPER_PPP
Number 179
Description Juniper Networks
Name LINKTYPE_JUNIPER_FRELAY
Number 180
Description Juniper Networks
Name LINKTYPE_JUNIPER_CHDLC
Number 181
Description Juniper Networks
Name LINKTYPE_MFR
Number 182
Description FRF.16.1 Multi-Link Frame Relay frames
Reference [LINKTYPE_MFR]
Name LINKTYPE_JUNIPER_VP
Number 183
Description Juniper Networks
Name LINKTYPE_A429
Number 184
Description ARINC 429 frames
Name LINKTYPE_A653_ICM
Number 185
Description Arinc 653 Interpartition Communication messages
Name LINKTYPE_USB_FREEBSD
Number 186
Description USB traffic captured on FreeBSD
Name LINKTYPE_BLUETOOTH_HCI_H4
Number 187
Description Bluetooth HCI UART Transport Layer packets
Reference [LINKTYPE_BLUETOOTH_HCI_H4]
Name LINKTYPE_IEEE802_16_MAC_CPS
Number 188
Description IEEE 802.16 MAC Common Part Sublayer
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Name LINKTYPE_USB_LINUX
Number 189
Description USB packets, beginning with a Linux USB header
Reference [LINKTYPE_USB_LINUX]
Name LINKTYPE_CAN20B
Number 190
Description Controller Area Network (CAN) v. 2.0B packets
Name LINKTYPE_IEEE802_15_4_LINUX
Number 191
Description IEEE 802.15.4 with address fields padded by Linux
Name LINKTYPE_PPI
Number 192
Description Per-Packet Information header preceding packet data
Reference [LINKTYPE_PPI]
Name LINKTYPE_IEEE802_16_MAC_CPS_RADIO
Number 193
Description 802.16 MAC Common Part Sublayer plus radio header
Name LINKTYPE_JUNIPER_ISM
Number 194
Description Juniper Networks
Name LINKTYPE_IEEE802_15_4_WITHFCS
Number 195
Description IEEE 802.15.4 with FCS
Reference [LINKTYPE_IEEE802_15_4_WITHFCS]
Name LINKTYPE_SITA
Number 196
Description Various link-layer types, with a pseudo-header
Reference [LINKTYPE_SITA]
Name LINKTYPE_ERF
Number 197
Description Endace ERF records
Reference [LINKTYPE_ERF]
Name LINKTYPE_RAIF1
Number 198
Description Ethernet packets captured from a u10 Networks board
Name LINKTYPE_IPMB_KONTRON
Number 199
Description IPMB packet for IPMI, with a 2-octet header
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Name LINKTYPE_JUNIPER_ST
Number 200
Description Juniper Networks
Name LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR
Number 201
Description Bluetooth HCI UART Transport Layer packets with a
direction pseudo-header
Reference [LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR]
Name LINKTYPE_AX25_KISS
Number 202
Description KISS frames between a host and an AX.25 TNC
Reference [LINKTYPE_AX25_KISS]
Name LINKTYPE_LAPD
Number 203
Description Q.921 LAPD frames
Reference [LINKTYPE_LAPD]
Name LINKTYPE_PPP_WITH_DIR
Number 204
Description PPP, with a direction header
Reference [LINKTYPE_PPP_WITH_DIR]
Name LINKTYPE_C_HDLC_WITH_DIR
Number 205
Description Cisco PPP with HDLC framing, with a direction header
Reference [LINKTYPE_C_HDLC_WITH_DIR]
Name LINKTYPE_FRELAY_WITH_DIR
Number 206
Description Frame Relay LAPF, with a direction header
Reference [LINKTYPE_FRELAY_WITH_DIR]
Name LINKTYPE_LAPB_WITH_DIR
Number 207
Description X.25 LAPB, with a direction header
Reference [LINKTYPE_LAPB_WITH_DIR]
Name WillBarker-Proprietary
Number 208
Description Proprietary Link-Layer type
Name LINKTYPE_I2C_LINUX
Number 209
Description Linux I2C packets
Reference [LINKTYPE_I2C_LINUX]
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Name LINKTYPE_FLEXRAY
Number 210
Description FlexRay frames or symbols, with a pseudo-header
Reference [LINKTYPE_FLEXRAY]
Name LINKTYPE_MOST
Number 211
Description Media Oriented Systems Transport (MOST) bus
Name LINKTYPE_LIN
Number 212
Description Local Interconnect Network (LIN) automotive bus, with a
metadata header
Reference [LINKTYPE_LIN]
Name LINKTYPE_X2E_SERIAL
Number 213
Description X2E serial line captures
Name LINKTYPE_X2E_XORAYA
Number 214
Description X2E Xoraya data loggers
Name LINKTYPE_IEEE802_15_4_NONASK_PHY
Number 215
Description IEEE 802.15.4 with PHY header
Reference [LINKTYPE_IEEE802_15_4_NONASK_PHY]
Name LINKTYPE_LINUX_EVDEV
Number 216
Description Linux evdev messages
Name LINKTYPE_GSMTAP_UM
Number 217
Description GSM Um interface, with gsmtap header
Name LINKTYPE_GSMTAP_ABIS
Number 218
Description GSM Abis interface, with gsmtap header
Name LINKTYPE_MPLS
Number 219
Description MPLS packets with MPLS label as the header
Name LINKTYPE_USB_LINUX_MMAPPED
Number 220
Description USB packets, beginning with an extended Linux USB header
Reference [LINKTYPE_USB_LINUX_MMAPPED]
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Name LINKTYPE_DECT
Number 221
Description DECT packets, with a pseudo-header
Name LINKTYPE_AOS
Number 222
Description OS Space Data Link Protocol
Name LINKTYPE_WIHART
Number 223
Description Wireless HART (Highway Addressable Remote Transducer)
Name LINKTYPE_FC_2
Number 224
Description Fibre Channel FC-2 frames
Reference [LINKTYPE_FC_2]
Name LINKTYPE_FC_2_WITH_FRAME_DELIMS
Number 225
Description Fibre Channel FC-2 frames with SOF and EOF
Reference [LINKTYPE_FC_2_WITH_FRAME_DELIMS]
Name LINKTYPE_IPNET
Number 226
Description Solaris ipnet
Reference [LINKTYPE_IPNET]
Name LINKTYPE_CAN_SOCKETCAN
Number 227
Description Controller Area Network (CAN) frames, with a metadata
header
Reference [LINKTYPE_CAN_SOCKETCAN]
Name LINKTYPE_IPV4
Number 228
Description IPv4 without link-layer headers
Reference [LINKTYPE_IPV4] [RFC791]
Name LINKTYPE_IPV6
Number 229
Description IPv6 without link-layer headers
Reference [LINKTYPE_IPV6] [RFC8200]
Name LINKTYPE_IEEE802_15_4_NOFCS
Number 230
Description IEEE 802.15.4 without FCS
Reference [LINKTYPE_IEEE802_15_4_NOFCS]
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Name LINKTYPE_DBUS
Number 231
Description D-Bus messages
Reference [LINKTYPE_DBUS]
Name LINKTYPE_JUNIPER_VS
Number 232
Description Juniper Networks
Name LINKTYPE_JUNIPER_SRX_E2E
Number 233
Description Juniper Networks
Name LINKTYPE_JUNIPER_FIBRECHANNEL
Number 234
Description Juniper Networks
Name LINKTYPE_DVB_CI
Number 235
Description DVB-CI messages, with a pseudo-header
Reference [DVB-CI-PCAP]
Name LINKTYPE_MUX27010
Number 236
Description Variant of 3GPP TS 27.010 multiplexing protocol
Reference [LINKTYPE_MUX27010]
Name LINKTYPE_STANAG_5066_D_PDU
Number 237
Description STANAG 5066 D_PDUs
Reference [LINKTYPE_STANAG_5066_D_PDU]
Name LINKTYPE_JUNIPER_ATM_CEMIC
Number 238
Description Juniper Networks
Name LINKTYPE_NFLOG
Number 239
Description Linux netlink NETLINK NFLOG socket log messages
Reference [LINKTYPE_NFLOG]
Name LINKTYPE_NETANALYZER
Number 240
Description Ethernet frames with netANALYZER pseudo-header
Reference [LINKTYPE_NETANALYZER]
Name LINKTYPE_NETANALYZER_TRANSPARENT
Number 241
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Description Ethernet frames with netANALYZER pseudo-header,
preamble, and SFD
Reference [LINKTYPE_NETANALYZER_TRANSPARENT]
Name LINKTYPE_IPOIB
Number 242
Description IP-over-InfiniBand
Reference [LINKTYPE_IPOIB]
Name LINKTYPE_MPEG_2_TS
Number 243
Description MPEG-2 Transport Stream transport packets
Reference [LINKTYPE_MPEG_2_TS]
Name LINKTYPE_NG40
Number 244
Description Frames from ng4T GmbH's ng40 protocol tester
Reference [LINKTYPE_NG40]
Name LINKTYPE_NFC_LLCP
Number 245
Description NFC Logical Link Control Protocol frames, with a pseudo-
header
Reference [LINKTYPE_NFC_LLCP]
Name LINKTYPE_PFSYNC
Number 246
Description pfsync output
Name LINKTYPE_INFINIBAND
Number 247
Description InfiniBand data packets
Reference [LINKTYPE_INFINIBAND]
Name LINKTYPE_SCTP
Number 248
Description SCTP packets, with no lower-level protocols such as IPv4
or IPv6
Reference [RFC9260]
Name LINKTYPE_USBPCAP
Number 249
Description USB packets, beginning with a USBPcap header
Reference [USBPcap]
Name LINKTYPE_RTAC_SERIAL
Number 250
Description Serial-line packet from the Schweitzer Engineering
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Laboratories RTAC product
Reference [LINKTYPE_RTAC_SERIAL]
Name LINKTYPE_BLUETOOTH_LE_LL
Number 251
Description Bluetooth Low Energy link-layer packets
Reference [LINKTYPE_BLUETOOTH_LE_LL]
Name LINKTYPE_WIRESHARK_UPPER_PDU
Number 252
Description Wireshark
Name LINKTYPE_NETLINK
Number 253
Description Linux Netlink capture encapsulation
Reference [LINKTYPE_NETLINK]
Name LINKTYPE_BLUETOOTH_LINUX_MONITOR
Number 254
Description Bluetooth Linux Monitor
Reference [LINKTYPE_BLUETOOTH_LINUX_MONITOR]
Name LINKTYPE_BLUETOOTH_BREDR_BB
Number 255
Description Bluetooth Basic Rate and Enhanced Data Rate baseband
packets
Reference [LINKTYPE_BLUETOOTH_BREDR_BB]
Name LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR
Number 256
Description Bluetooth Low Energy link-layer packets
Reference [LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR]
Name LINKTYPE_PROFIBUS_DL
Number 257
Description PROFIBUS data link layer packets
Reference [LINKTYPE_PROFIBUS_DL]
Name LINKTYPE_PKTAP
Number 258
Description Apple PKTAP capture encapsulation
Reference [LINKTYPE_PKTAP]
Name LINKTYPE_EPON
Number 259
Description Ethernet-over-passive-optical-network packets, including
preamble octets
Reference [LINKTYPE_EPON]
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Name LINKTYPE_IPMI_HPM_2
Number 260
Description IPMI HPM.2 trace packets
Reference [LINKTYPE_IPMI_HPM_2]
Name LINKTYPE_ZWAVE_R1_R2
Number 261
Description Z-Wave RF profile R1 and R2 packets
Reference [LINKTYPE_ZWAVE_R1_R2]
Name LINKTYPE_ZWAVE_R3
Number 262
Description Z-Wave RF profile R3 packets
Reference [LINKTYPE_ZWAVE_R3]
Name LINKTYPE_WATTSTOPPER_DLM
Number 263
Description WattStopper Digital Lighting Management (DLM) and
Legrand Nitoo Open protocol packets
Reference [LINKTYPE_WATTSTOPPER_DLM]
Name LINKTYPE_ISO_14443
Number 264
Description ISO 14443 contactless smartcard messages
Reference [ISO-14443-PCAP]
Name LINKTYPE_RDS
Number 265
Description IEC 62106 Radio data system (RDS) groups
Reference [LINKTYPE_RDS]
Name LINKTYPE_USB_DARWIN
Number 266
Description USB packets captured on a Darwin-based operating system
(macOS, etc.)
Reference [LINKTYPE_USB_DARWIN]
Name LINKTYPE_OPENFLOW
Number 267
Description OpenBSD DLT_OPENFLOW
Name LINKTYPE_SDLC
Number 268
Description SNA SDLC packets
Reference [LINKTYPE_SDLC]
Name LINKTYPE_TI_LLN_SNIFFER
Number 269
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Description Texas Instruments protocol sniffer
Name LINKTYPE_LORATAP
Number 270
Description LoRaWan packets with a LoRaTap pseudo-header
Reference [LINKTYPE_LORATAP]
Name LINKTYPE_VSOCK
Number 271
Description Protocol for communication between host and guest
machines in VMware and KVM hypervisors
Reference [LINKTYPE_VSOCK]
Name LINKTYPE_NORDIC_BLE
Number 272
Description Messages to and from a Nordic Semiconductor nRF Sniffer
for Bluetooth LE packets
Reference [LINKTYPE_NORDIC_BLE]
Name LINKTYPE_DOCSIS31_XRA31
Number 273
Description DOCSIS packets and bursts, preceded by a pseudo-header
Reference [DOCSIS-XRA] [DOCSIS-4.0-MULP]
Name LINKTYPE_ETHERNET_MPACKET
Number 274
Description IEEE 802.3 mPackets
Reference [LINKTYPE_ETHERNET_MPACKET]
Name LINKTYPE_DISPLAYPORT_AUX
Number 275
Description DisplayPort AUX channel monitoring messages
Reference [LINKTYPE_DISPLAYPORT_AUX]
Name LINKTYPE_LINUX_SLL2
Number 276
Description Linux cooked capture encapsulation v2
Reference [LINKTYPE_LINUX_SLL2]
Name LINKTYPE_SERCOS_MONITOR
Number 277
Description Sercos Monitor
Name LINKTYPE_OPENVIZSLA
Number 278
Description OpenVizsla FPGA-based USB sniffer
Reference [OpenVizsla]
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Name LINKTYPE_EBHSCR
Number 279
Description Elektrobit High Speed Capture and Replay (EBHSCR) format
Reference [EBHSCR]
Name LINKTYPE_VPP_DISPATCH
Number 280
Description fd.io VPP graph dispatcher trace records
Reference [FD.io-VPP]
Name LINKTYPE_DSA_TAG_BRCM
Number 281
Description Ethernet frames, with a Broadcom switch tag inserted
Reference [LINKTYPE_DSA_TAG_BRCM]
Name LINKTYPE_DSA_TAG_BRCM_PREPEND
Number 282
Description Ethernet frames, with a Broadcom switch tag prepended
Reference [LINKTYPE_DSA_TAG_BRCM_PREPEND]
Name LINKTYPE_IEEE802_15_4_TAP
Number 283
Description IEEE 802.15.4 with a tap header preceding it
Reference [Exegin-802.15.4-TAP]
Name LINKTYPE_DSA_TAG_DSA
Number 284
Description Ethernet frames, with a Marvell DSA switch tag inserted
Reference [LINKTYPE_DSA_TAG_DSA]
Name LINKTYPE_DSA_TAG_EDSA
Number 285
Description Ethernet frames, with a Marvell EDSA switch tag inserted
Reference [LINKTYPE_DSA_TAG_EDSA]
Name LINKTYPE_ELEE
Number 286
Description ELEE lawful intercept protocol
Name LINKTYPE_Z_WAVE_SERIAL
Number 287
Description Serial frames transmitted between a host and a Z-Wave
chip over an RS-232 or USB serial connection
Reference [Z_WAVE_SERIAL] section 5
Name LINKTYPE_USB_2_0
Number 288
Description USB 2.0, 1.1, or 1.0 packets
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Reference [LINKTYPE_USB_2_0]
Name LINKTYPE_ATSC_ALP
Number 289
Description ATSC Link-Layer Protocol frames
Reference [LINKTYPE_ATSC_ALP]
Name LINKTYPE_ETW
Number 290
Description Event Tracing for Windows messages
Reference [LINKTYPE_ETW]
Name LINKTYPE_NETANALYZER_NG
Number 291
Description Hilscher Gesellschaft fuer Systemautomation mbH
netANALYZER NG hardware and software
Name LINKTYPE_ZBOSS_NCP
Number 292
Description ZBOSS NCP Serial Protocol, with a pseudo-header
Reference [LINKTYPE_ZBOSS_NCP]
Name LINKTYPE_USB_2_0_LOW_SPEED
Number 293
Description Low-Speed USB 2.0, 1.1, or 1.0 packets
Reference [LINKTYPE_USB_2_0_LOW_SPEED]
Name LINKTYPE_USB_2_0_FULL_SPEED
Number 294
Description Full-Speed USB 2.0, 1.1, or 1.0 packets
Reference [LINKTYPE_USB_2_0_FULL_SPEED]
Name LINKTYPE_USB_2_0_HIGH_SPEED
Number 295
Description High-Speed USB 2.0 packets
Reference [LINKTYPE_USB_2_0_HIGH_SPEED]
Name LINKTYPE_AUERSWALD_LOG
Number 296
Description Auerswald Logger Protocol
Reference [Auerswald-Logger]
Name LINKTYPE_ZWAVE_TAP
Number 297
Description Z-Wave packets, with a metadata header
Reference [LINKTYPE_ZWAVE_TAP]
Name LINKTYPE_SILABS_DEBUG_CHANNEL
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Number 298
Description Silicon Labs debug channel protocol
Reference [Silabs-Debug-Channel]
Name LINKTYPE_FIRA_UCI
Number 299
Description Ultra-wideband (UWB) controller interface protocol (UCI)
Reference [LINKTYPE_FIRA_UCI]
Name LINKTYPE_MDB
Number 300
Description MDB (Multi-Drop Bus) protocol
Reference [MDB-PCAP]
Name LINKTYPE_DECT_NR
Number 301
Description DECT-2020 New Radio (NR) MAC layer
Reference [LINKTYPE_DECT_NR]
2.2.2. Guidance for Designated Experts
When processing a request for an allocation, the Designated Experts
will encourage the requester to provide a specification at a stable
URL.
There is no requirement for a specification, but often review of the
specification allows the Designated Expert to determine if the
allocation actually is a duplicate of another specification.
When the contents of the link type can contain an IPv4 or IPv6
header, then the octets between the beginning of the link type and
the IP header needs to be clearly specified.
Specifications that are not publicly available, but which may be
obtained via liaison agreements (such as to ITU-T, drafts, IEEE,
etc.) are acceptable particularly if the specification document will
be public eventually. This includes specifications that might be
subject to a security classification for which no public document
will ever be made. The minimal requirement is to provide a contact
person for that link type.
For other documents, the Designated Expert will need use their
judgement, or consult the OPSAWG or an Area Director.
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3. Security Considerations
This document describes the IANA registration rules for the LinkType
encapsulations. PCAP-related packet file formats use this value to
determine what kind of headers precede network packet captures. Many
of these formats can contain IPv4 and IPv6 packets. A system reading
PCAP-related format captures can be subject to arbitrary inputs that
may be controlled by malicious entities, so utmost caution is
required.
Many LinkType formats include a "snapshot" length, which may be
smaller than the actual packet. It is therefore very likely that
trailing parts of a packet capture may be omitted, yet internal
length fields in the packets will claim the packet is bigger than the
capture. This leads to trivial buffer overreads, and systems
interpreting the packets need to carefully scrutinize all attempts to
read data from a capture.
4. Contributors
PCAP has been developed over three and half decades by a variety of
developers, including: Bill Fenner, Denis Ovsienko, Francois-Xavier
Le Bail, Fulvio Risso, Gerald Combs, Gianluca Varenni, Gisle Vanem,
Hannes Gredler, Joerg Mayer, Michal Sekletar, Stephen Donnelly,
Torsten Landschoff, and Jun-ichiro itojun Hagino.
PCAP was originally created at LBL by Steve McCanne, Craig Leres, and
Van Jacobson.
5. Acknowledgments
The authors wish to thank: Michael Tuexen, Mohamed Boucadair, Carsten
Bormann, Henk Birkholtz, and Robert Wilton their invaluable comments
and encouragement.
6. References
6.1. Normative References
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/rfc/rfc8126>.
6.2. Informative References
[TCPDUMP] "LINK-LAYER HEADER TYPES",
<https://www.tcpdump.org/linktypes.html>.
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[LIBPCAP] "libpcap", <https://github.com/the-tcpdump-group/libpcap>.
[Wireshark]
"Homepage of Wireshark", <https://www.wireshark.org>.
[_3GPP-TS-04.64]
"Digital cellular telecommunications system (Phase 2+);
General Packet Radio Service (GPRS); Mobile Station -
Serving GPRS Support Node (MS-SGSN) Logical Link Control
(LLC) layer specification", 3GPP TS 04.64.
[AIM-628] Moon, D. A., "Chaosnet", MIT A.I. Memo No. 628, June 1981,
<http://www.bitsavers.org/pdf/mit/ai/AIM-
628_chaosnet.pdf>.
[Auerswald-Logger]
"Packet structure", n.d., <https://github.com/Auerswald-
GmbH/auerlog/blob/master/auerlog.txt>.
[AVS] Peachy, S., "AVS Capture Frame Format Version 2",
<http://web.archive.org/web/20040803232023/
http://www.shaftnet.org/~pizza/software/capturefrm.txt>.
[DOCSIS-4.0-MULP]
"DOCSIS 4.0 MAC and Upper Layer Protocols Interface
Specification", <https://www.cablelabs.com/specifications/
CM-SP-MULPIv4.0>.
[DOCSIS-XRA]
"Excentis XRA Header Definition",
<https://support.excentis.com/knowledge/article/45>.
[DVB-CI-PCAP]
Kaiser, M., "PCAP format for DVB-CI", January 2021,
<https://www.kaiser.cx/posts/pcap-dvbci/>.
[EBHSCR] "Documentation EBHSCR",
<http://www.elektrobit.com/ebhscr>.
[Exegin-802.15.4-TAP]
"IEEE 802.15.4 TAP Link Type Specification",
<https://gitlab.com/exegin/ieee802-15-4-tap>.
[FD.io-VPP]
"VNET (VPP Network Stack)", <https://fdio-
vpp.readthedocs.io/en/latest/gettingstarted/developers/
vnet.html>.
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[G.7041] "Generic Framing Procedure", ITU-T Recommendation G.7041/
Y.1303, <https://www.itu.int/rec/T-REC-G.7041/en>.
[ISO-14443-PCAP]
Kaiser, M., "PCAP format for ISO14443", January 2021,
<https://www.kaiser.cx/posts/pcap-iso14443/>.
[LINKTYPE_APPLE_IP_OVER_IEEE1394]
"LINKTYPE_APPLE_IP_OVER_IEEE1394",
<https://www.tcpdump.org/linktypes/
LINKTYPE_APPLE_IP_OVER_IEEE1394.html>.
[LINKTYPE_ATM_RFC1483]
"LINKTYPE_ATM_RFC1483",
<https://www.tcpdump.org/linktypes/
LINKTYPE_ATM_RFC1483.html>.
[LINKTYPE_ATSC_ALP]
"LINKTYPE_ATSC_ALP", <https://www.tcpdump.org/linktypes/
LINKTYPE_ATSC_ALP.html>.
[LINKTYPE_AX25]
"LINKTYPE_AX25",
<https://www.tcpdump.org/linktypes/LINKTYPE_AX25.html>.
[LINKTYPE_AX25_KISS]
"LINKTYPE_AX25_KISS", <https://www.tcpdump.org/linktypes/
LINKTYPE_AX25_KISS.html>.
[LINKTYPE_BACNET_MS_TP]
"LINKTYPE_BACNET_MS_TP",
<https://www.tcpdump.org/linktypes/
LINKTYPE_BACNET_MS_TP.html>.
[LINKTYPE_BLUETOOTH_BREDR_BB]
"LINKTYPE_BLUETOOTH_BREDR_BB",
<https://www.tcpdump.org/linktypes/
LINKTYPE_BLUETOOTH_BREDR_BB.html>.
[LINKTYPE_BLUETOOTH_HCI_H4]
"LINKTYPE_BLUETOOTH_HCI_H4",
<https://www.tcpdump.org/linktypes/
LINKTYPE_BLUETOOTH_HCI_H4.html>.
[LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR]
"LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR",
<https://www.tcpdump.org/linktypes/
LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR.html>.
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[LINKTYPE_BLUETOOTH_LE_LL]
"LINKTYPE_BLUETOOTH_LE_LL",
<https://www.tcpdump.org/linktypes/
LINKTYPE_BLUETOOTH_LE_LL.html>.
[LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR]
"LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR",
<https://www.tcpdump.org/linktypes/
LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR.html>.
[LINKTYPE_BLUETOOTH_LINUX_MONITOR]
"LINKTYPE_BLUETOOTH_LINUX_MONITOR",
<https://www.tcpdump.org/linktypes/
LINKTYPE_BLUETOOTH_LINUX_MONITOR.html>.
[LINKTYPE_C_HDLC]
"LINKTYPE_C_HDLC",
<https://www.tcpdump.org/linktypes/LINKTYPE_C_HDLC.html>.
[LINKTYPE_C_HDLC_WITH_DIR]
"LINKTYPE_C_HDLC_WITH_DIR",
<https://www.tcpdump.org/linktypes/
LINKTYPE_C_HDLC_WITH_DIR.html>.
[LINKTYPE_CAN_SOCKETCAN]
"LINKTYPE_CAN_SOCKETCAN",
<https://www.tcpdump.org/linktypes/
LINKTYPE_CAN_SOCKETCAN.html>.
[LINKTYPE_DBUS]
"LINKTYPE_DBUS",
<https://www.tcpdump.org/linktypes/LINKTYPE_DBUS.html>.
[LINKTYPE_DECT_NR]
"LINKTYPE_DECT_NR",
<https://www.tcpdump.org/linktypes/LINKTYPE_DECT_NR.html>.
[LINKTYPE_DISPLAYPORT_AUX]
"LINKTYPE_DISPLAYPORT_AUX",
<https://www.tcpdump.org/linktypes/
LINKTYPE_DISPLAYPORT_AUX.html>.
[LINKTYPE_DSA_TAG_BRCM]
"LINKTYPE_DSA_TAG_BRCM",
<https://www.tcpdump.org/linktypes/
LINKTYPE_DSA_TAG_BRCM.html>.
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[LINKTYPE_DSA_TAG_BRCM_PREPEND]
"LINKTYPE_DSA_TAG_BRCM_PREPEND",
<https://www.tcpdump.org/linktypes/
LINKTYPE_DSA_TAG_BRCM_PREPEND.html>.
[LINKTYPE_DSA_TAG_DSA]
"LINKTYPE_DSA_TAG_DSA",
<https://www.tcpdump.org/linktypes/
LINKTYPE_DSA_TAG_DSA.html>.
[LINKTYPE_DSA_TAG_EDSA]
"LINKTYPE_DSA_TAG_EDSA",
<https://www.tcpdump.org/linktypes/
LINKTYPE_DSA_TAG_EDSA.html>.
[LINKTYPE_ETHERNET]
"IEEE 802.3 Ethernet",
<https://ieeexplore.ieee.org/document/9844436>.
[LINKTYPE_EPON]
"LINKTYPE_EPON",
<https://www.tcpdump.org/linktypes/LINKTYPE_EPON.html>.
[LINKTYPE_ERF]
"LINKTYPE_ERF",
<https://www.tcpdump.org/linktypes/LINKTYPE_ERF.html>.
[LINKTYPE_ETW]
"LINKTYPE_ETW",
<https://www.tcpdump.org/linktypes/LINKTYPE_ETW.html>.
[LINKTYPE_ETHERNET_MPACKET]
"LINKTYPE_ETHERNET_MPACKET",
<https://www.tcpdump.org/linktypes/
LINKTYPE_ETHERNET_MPACKET.html>.
[LINKTYPE_FC_2]
"LINKTYPE_FC_2",
<https://www.tcpdump.org/linktypes/LINKTYPE_FC_2.html>.
[LINKTYPE_FC_2_WITH_FRAME_DELIMS]
"LINKTYPE_FC_2_WITH_FRAME_DELIMS",
<https://www.tcpdump.org/linktypes/
LINKTYPE_FC_2_WITH_FRAME_DELIMSa.html>.
[LINKTYPE_FIRA_UCI]
"LINKTYPE_FIRA_UCI", <https://www.tcpdump.org/linktypes/
LINKTYPE_FIRA_UCI.html>.
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[LINKTYPE_FLEXRAY]
"LINKTYPE_FLEXRAY",
<https://www.tcpdump.org/linktypes/LINKTYPE_FLEXRAY.html>.
[LINKTYPE_FRELAY]
"LINKTYPE_FRELAY",
<https://www.tcpdump.org/linktypes/LINKTYPE_FRELAY.html>.
[LINKTYPE_FRELAY_WITH_DIR]
"LINKTYPE_FRELAY_WITH_DIR",
<https://www.tcpdump.org/linktypes/
LINKTYPE_FRELAY_WITH_DIR.html>.
[LINKTYPE_I2C_LINUX]
"LINKTYPE_I2C_LINUX", <https://www.tcpdump.org/linktypes/
LINKTYPE_I2C_LINUX.html>.
[LINKTYPE_IEEE802_11_PRISM]
"LINKTYPE_IEEE802_11_PRISM",
<https://www.tcpdump.org/linktypes/
LINKTYPE_IEEE802_11_PRISM.html>.
[LINKTYPE_IEEE802_15_4_NOFCS]
"LINKTYPE_IEEE802_15_4_NOFCS",
<https://www.tcpdump.org/linktypes/
LINKTYPE_IEEE802_15_4_NOFCS.html>.
[LINKTYPE_IEEE802_15_4_NONASK_PHY]
"LINKTYPE_IEEE802_15_4_NONASK_PHY",
<https://www.tcpdump.org/linktypes/
LINKTYPE_IEEE802_15_4_NONASK_PHY.html>.
[LINKTYPE_IEEE802_15_4_WITHFCS]
"LINKTYPE_IEEE802_15_4_WITHFCS",
<https://www.tcpdump.org/linktypes/
LINKTYPE_IEEE802_15_4_WITHFCS.html>.
[LINKTYPE_IPV4]
"LINKTYPE_IPV4",
<https://www.tcpdump.org/linktypes/LINKTYPE_IPV4.html>.
[LINKTYPE_IPV6]
"LINKTYPE_IPV6",
<https://www.tcpdump.org/linktypes/LINKTYPE_IPV6.html>.
[LINKTYPE_IPOIB]
"LINKTYPE_IPOIB",
<https://www.tcpdump.org/linktypes/LINKTYPE_IPOIB.html>.
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[LINKTYPE_IP_OVER_FC]
"LINKTYPE_IP_OVER_FC", <https://www.tcpdump.org/linktypes/
LINKTYPE_IP_OVER_FC.html>.
[LINKTYPE_INFINIBAND]
"LINKTYPE_INFINIBAND", <https://www.tcpdump.org/linktypes/
LINKTYPE_INFINIBAND.html>.
[LINKTYPE_IPMI_HPM_2]
"LINKTYPE_IPMI_HPM_2", <https://www.tcpdump.org/linktypes/
LINKTYPE_IPMI_HPM_2.html>.
[LINKTYPE_IPNET]
"LINKTYPE_IPNET",
<https://www.tcpdump.org/linktypes/LINKTYPE_IPNET.html>.
[LINKTYPE_LAPB_WITH_DIR]
"LINKTYPE_LAPB_WITH_DIR",
<https://www.tcpdump.org/linktypes/
LINKTYPE_LAPB_WITH_DIR.html>.
[LINKTYPE_LAPD]
"LINKTYPE_LAPD",
<https://www.tcpdump.org/linktypes/LINKTYPE_LAPD.html>.
[LINKTYPE_LIN]
"LINKTYPE_LIN",
<https://www.tcpdump.org/linktypes/LINKTYPE_LIN.html>.
[LINKTYPE_LINUX_IRDA]
"LINKTYPE_LINUX_IRDA", <https://www.tcpdump.org/linktypes/
LINKTYPE_LINUX_IRDA.html>.
[LINKTYPE_LINUX_LAPD]
"LINKTYPE_LINUX_LAPD", <https://www.tcpdump.org/linktypes/
LINKTYPE_LINUX_LAPD.html>.
[LINKTYPE_LINUX_SLL]
"LINKTYPE_LINUX_SLL", <https://www.tcpdump.org/linktypes/
LINKTYPE_LINUX_SLL.html>.
[LINKTYPE_LINUX_SLL2]
"LINKTYPE_LINUX_SLL2", <https://www.tcpdump.org/linktypes/
LINKTYPE_LINUX_SLL2.html>.
[LINKTYPE_LOOP]
"LINKTYPE_LOOP",
<https://www.tcpdump.org/linktypes/LINKTYPE_LOOP.html>.
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[LINKTYPE_LORATAP]
"LINKTYPE_LORATAP",
<https://www.tcpdump.org/linktypes/LINKTYPE_LORATAP.html>.
[LINKTYPE_LTALK]
"LINKTYPE_LTALK",
<https://www.tcpdump.org/linktypes/LINKTYPE_LTALK.html>.
[LINKTYPE_MFR]
"LINKTYPE_MFR",
<https://www.tcpdump.org/linktypes/LINKTYPE_MFR.html>.
[LINKTYPE_MPEG_2_TS]
"LINKTYPE_MPEG_2_TS", <https://www.tcpdump.org/linktypes/
LINKTYPE_MPEG_2_TS.html>.
[LINKTYPE_MTP2]
"LINKTYPE_MTP2",
<https://www.tcpdump.org/linktypes/LINKTYPE_MTP2.html>.
[LINKTYPE_MTP2_WITH_PHDR]
"LINKTYPE_MTP2_WITH_PHDR",
<https://www.tcpdump.org/linktypes/
LINKTYPE_MTP2_WITH_PHDR.html>.
[LINKTYPE_MTP3]
"LINKTYPE_MTP3",
<https://www.tcpdump.org/linktypes/LINKTYPE_MTP3.html>.
[LINKTYPE_SCCP]
"LINKTYPE_SCCP",
<https://www.tcpdump.org/linktypes/LINKTYPE_SCCP.html>.
[LINKTYPE_MUX27010]
"LINKTYPE_MUX27010", <https://www.tcpdump.org/linktypes/
LINKTYPE_MUX27010.html>.
[LINKTYPE_NETANALYZER]
"LINKTYPE_NETANALYZER",
<https://www.tcpdump.org/linktypes/
LINKTYPE_NETANALYZER.html>.
[LINKTYPE_NETANALYZER_TRANSPARENT]
"LINKTYPE_NETANALYZER_TRANSPARENT",
<https://www.tcpdump.org/linktypes/
LINKTYPE_NETANALYZER_TRANSPARENT.html>.
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[LINKTYPE_NETLINK]
"LINKTYPE_NETLINK",
<https://www.tcpdump.org/linktypes/LINKTYPE_NETLINK.html>.
[LINKTYPE_NFC_LLCP]
"LINKTYPE_NFC_LLCP", <https://www.tcpdump.org/linktypes/
LINKTYPE_NFC_LLCP.html>.
[LINKTYPE_NFLOG]
"LINKTYPE_NFLOG",
<https://www.tcpdump.org/linktypes/LINKTYPE_NFLOG.html>.
[LINKTYPE_NG40]
"LINKTYPE_NG40",
<https://www.tcpdump.org/linktypes/LINKTYPE_NG40.html>.
[LINKTYPE_NORDIC_BLE]
"LINKTYPE_NORDIC_BLE", <https://www.tcpdump.org/linktypes/
LINKTYPE_NORDIC_BLE.html>.
[LINKTYPE_NULL]
"LINKTYPE_NULL",
<https://www.tcpdump.org/linktypes/LINKTYPE_NULL.html>.
[LINKTYPE_PKTAP]
"LINKTYPE_PKTAP",
<https://www.tcpdump.org/linktypes/LINKTYPE_PKTAP.html>.
[LINKTYPE_PPI]
"LINKTYPE_PPI",
<https://www.tcpdump.org/linktypes/LINKTYPE_PPI.html>.
[LINKTYPE_PPP]
"LINKTYPE_PPP",
<https://www.tcpdump.org/linktypes/LINKTYPE_PPP.html>.
[LINKTYPE_PPP_ETHER]
"LINKTYPE_PPP_ETHER", <https://www.tcpdump.org/linktypes/
LINKTYPE_PPP_ETHER.html>.
[LINKTYPE_PPP_HDLC]
"LINKTYPE_PPP_HDLC", <https://www.tcpdump.org/linktypes/
LINKTYPE_PPP_HDLC.html>.
[LINKTYPE_PPP_PPPD]
"LINKTYPE_PPP_PPPD", <https://www.tcpdump.org/linktypes/
LINKTYPE_PPP_PPPD.html>.
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[LINKTYPE_PPP_WITH_DIR]
"LINKTYPE_PPP_WITH_DIR",
<https://www.tcpdump.org/linktypes/
LINKTYPE_PPP_WITH_DIR.html>.
[LINKTYPE_PROFIBUS_DL]
"LINKTYPE_PROFIBUS_DL",
<https://www.tcpdump.org/linktypes/
LINKTYPE_PROFIBUS_DL.html>.
[LINKTYPE_RAW]
"LINKTYPE_RAW",
<https://www.tcpdump.org/linktypes/LINKTYPE_RAW.html>.
[LINKTYPE_RDS]
"LINKTYPE_RDS",
<https://www.tcpdump.org/linktypes/LINKTYPE_RDS.html>.
[LINKTYPE_RTAC_SERIAL]
"LINKTYPE_RTAC_SERIAL",
<https://www.tcpdump.org/linktypes/
LINKTYPE_RTAC_SERIAL.html>.
[LINKTYPE_SDLC]
"LINKTYPE_SDLC",
<https://www.tcpdump.org/linktypes/LINKTYPE_SDLC.html>.
[LINKTYPE_SITA]
"LINKTYPE_SITA",
<https://www.tcpdump.org/linktypes/LINKTYPE_SITA.html>.
[LINKTYPE_SLIP]
"LINKTYPE_SLIP",
<https://www.tcpdump.org/linktypes/LINKTYPE_SLIP.html>.
[LINKTYPE_STANAG_5066_D_PDU]
"LINKTYPE_STANAG_5066_D_PDU",
<https://www.tcpdump.org/linktypes/
LINKTYPE_STANAG_5066_D_PDU.html>.
[LINKTYPE_SUNATM]
"LINKTYPE_SUNATM",
<https://www.tcpdump.org/linktypes/LINKTYPE_SUNATM.html>.
[LINKTYPE_USB_2_0]
"LINKTYPE_USB_2_0",
<https://www.tcpdump.org/linktypes/LINKTYPE_USB_2_0.html>.
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Internet-Draft pcaplinktype December 2025
[LINKTYPE_USB_2_0_FULL_SPEED]
"LINKTYPE_USB_2_0_FULL_SPEED",
<https://www.tcpdump.org/linktypes/
LINKTYPE_USB_2_0_FULL_SPEED.html>.
[LINKTYPE_USB_2_0_HIGH_SPEED]
"LINKTYPE_USB_2_0_HIGH_SPEED",
<https://www.tcpdump.org/linktypes/
LINKTYPE_USB_2_0_HIGH_SPEED.html>.
[LINKTYPE_USB_2_0_LOW_SPEED]
"LINKTYPE_USB_2_0_LOW_SPEED",
<https://www.tcpdump.org/linktypes/
LINKTYPE_USB_2_0_LOW_SPEED.html>.
[LINKTYPE_USB_DARWIN]
"LINKTYPE_USB_DARWIN", <https://www.tcpdump.org/linktypes/
LINKTYPE_USB_DARWIN.html>.
[LINKTYPE_USB_LINUX]
"LINKTYPE_USB_LINUX", <https://www.tcpdump.org/linktypes/
LINKTYPE_USB_LINUX.html>.
[LINKTYPE_USB_LINUX_MMAPPED]
"LINKTYPE_USB_LINUX_MMAPPED",
<https://www.tcpdump.org/linktypes/
LINKTYPE_USB_LINUX_MMAPPED.html>.
[LINKTYPE_VSOCK]
"LINKTYPE_VSOCK",
<https://www.tcpdump.org/linktypes/LINKTYPE_VSOCK.html>.
[LINKTYPE_WATTSTOPPER_DLM]
"LINKTYPE_WATTSTOPPER_DLM",
<https://www.tcpdump.org/linktypes/
LINKTYPE_WATTSTOPPER_DLM.html>.
[LINKTYPE_ZBOSS_NCP]
"LINKTYPE_ZBOSS_NCP", <https://www.tcpdump.org/linktypes/
LINKTYPE_ZBOSS_NCP.html>.
[LINKTYPE_ZWAVE_R1_R2]
"LINKTYPE_ZWAVE_R1_R2",
<https://www.tcpdump.org/linktypes/
LINKTYPE_ZWAVE_R1_R2.html>.
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[LINKTYPE_ZWAVE_R3]
"LINKTYPE_ZWAVE_R3", <https://www.tcpdump.org/linktypes/
LINKTYPE_ZWAVE_R3.html>.
[LINKTYPE_ZWAVE_TAP]
"LINKTYPE_ZWAVE_TAP", <https://www.tcpdump.org/linktypes/
LINKTYPE_ZWAVE_TAP.html>.
[MDB-PCAP] Kaiser, M., "PCAP format for MDB", August 2023,
<https://www.kaiser.cx/posts/pcap-mdb/>.
[OpenVizsla]
"OpenVizsla protocol description", August 2018,
<https://github.com/matwey/libopenvizsla/wiki/OpenVizsla-
protocol-description>.
[PracConsEthDesign]
Crane, R. C. and E. A. Taft, "Practical Considerations in
Ethernet Local Network Design", February 1980,
<http://bitsavers.org/pdf/xerox/ethernet_3mb/Practical_Con
siderations_in_Ethernet_Local_Network_Design_Feb1980.pdf>.
[Radiotap] radiotap.org, "Radiotap Web site",
<https://www.radiotap.org>.
[Silabs-Debug-Channel]
"Silabs Debug Channel Format", n.d., <https://github.com/S
iliconLabs/java_packet_trace_library/blob/master/doc/
debug-channel.md>.
[USBPcap] "USBPcap Capture format specification",
<https://desowin.org/usbpcap/captureformat.html>.
[Z_WAVE_SERIAL]
"Z-Wave Serial API Host Application Programming Guide",
<https://www.silabs.com/documents/public/user-guides/
INS12350-Serial-API-Host-Appl.-Prg.-Guide.pdf>.
[I-D.ietf-opsawg-pcap]
Harris, G. and M. Richardson, "PCAP Capture File Format",
Work in Progress, Internet-Draft, draft-ietf-opsawg-pcap-
06, 3 September 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-opsawg-
pcap-06>.
[I-D.ietf-opsawg-pcapng]
Tüxen, M., Risso, F., Bongertz, J., Combs, G., Harris, G.,
Chaudron, E., and M. Richardson, "PCAP Now Generic
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Internet-Draft pcaplinktype December 2025
(pcapng) Capture File Format", Work in Progress, Internet-
Draft, draft-ietf-opsawg-pcapng-04, 30 August 2025,
<https://datatracker.ietf.org/doc/html/draft-ietf-opsawg-
pcapng-04>.
[RFC791] Postel, J., "Internet Protocol", STD 5, RFC 791,
DOI 10.17487/RFC0791, September 1981,
<https://www.rfc-editor.org/rfc/rfc791>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/rfc/rfc8200>.
[RFC9260] Stewart, R., Tüxen, M., and K. Nielsen, "Stream Control
Transmission Protocol", RFC 9260, DOI 10.17487/RFC9260,
June 2022, <https://www.rfc-editor.org/rfc/rfc9260>.
Authors' Addresses
Guy Harris (editor)
Email: gharris@sonic.net
Michael C. Richardson
Sandelman Software Works Inc
Email: mcr+ietf@sandelman.ca
URI: http://www.sandelman.ca/
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