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Versions: 00 01 02                                                      
Network Working Group                                     G. Harris, Ed.
Internet-Draft
Intended status: Informational                             M. Richardson
Expires: 25 December 2021                                      Sandelman
                                                            23 June 2021


                        PCAP Capture File Format
                      draft-gharris-opsawg-pcap-02

Abstract

   This document describes the format used by the libpcap library to
   record captured packets to a file.  Programs using the libpcap
   library to read and write those files, and thus reading and writing
   files in that format, include tcpdump.

Discussion Venues

   This note is to be removed before publishing as an RFC.

   Discussion of this document takes place on the OPSAWG Working Group
   mailing list (opsawg@ietf.org), which is archived at
   https://mailarchive.ietf.org/arch/browse/opsawg/.

   Source for this draft and an issue tracker can be found at
   https://github.com/pcapng/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 25 December 2021.







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Copyright Notice

   Copyright (c) 2021 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 Simplified BSD License text
   as described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  General File Structure  . . . . . . . . . . . . . . . . . . .   3
   4.  File Header . . . . . . . . . . . . . . . . . . . . . . . . .   3
   5.  Packet Record . . . . . . . . . . . . . . . . . . . . . . . .   5
   6.  Recommended File Name Extension: .pcap  . . . . . . . . . . .   7
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   7
     8.1.  Media-Type Registry . . . . . . . . . . . . . . . . . . .   7
       8.1.1.  application/pcap  . . . . . . . . . . . . . . . . . .   7
     8.2.  LinkType Registry . . . . . . . . . . . . . . . . . . . .   8
   9.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  34
   10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  35
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  35
     11.1.  Normative References . . . . . . . . . . . . . . . . . .  35
     11.2.  Informative References . . . . . . . . . . . . . . . . .  35
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  35

1.  Introduction

   In the late 1980's, 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.

   This document describes the format used by tcpdump, and other
   programs using libpcap, to read and write network traces.






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2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

3.  General File Structure

   A capture file begins with a File Header, followed by zero or more
   Packet Records, one per packet.

   All fields in the File Header and in Packet Records will always be
   saved according to the characteristics (little endian / big endian)
   of the capturing machine.  This refers to all the fields that are
   saved as numbers and that span over two or more octets.

   The approach of having the file saved in the native format of the
   generating host is more efficient because it avoids translation of
   data when reading / writing on the host itself, which is the most
   common case when generating/processing capture captures.

   The packets are shown in traditional IETF diagram, with the bits
   numbered from the left to the right.  The bit numbering does not
   reflect the binary value position, as IETF protocols are
   traditionally in big-endian network-byte order.  The most significant
   bit is therefore on the left in this diagram as if the file is being
   stored on a big-endian system.

4.  File Header

   The File Header has the following format:


















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                            1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     0 |                          Magic Number                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     4 |          Major Version        |         Minor Version         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     8 |                           Reserved1                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    12 |                           Reserved2                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    16 |                            SnapLen                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    20 | FCS |f|0 0 0 0 0 0 0 0 0 0 0 0|         LinkType              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                         Figure 1: File Header

   The File Header length is 24 octets.

   The meaning of the fields in the File Header is:

   Magic Number (32 bits):  an unsigned magic number, whose value is
      either the hexadecimal number 0xA1B2C3D4 or the hexadecimal number
      0xA1B23C4D.

      If the value is 0xA1B2C3D4, time stamps in Packet Records (see
      Figure 2) are in seconds and microseconds; if it is 0xA1B23C4D,
      time stamps in Packet Records are in seconds and nanoseconds.

      These numbers can be used to distinguish sessions that have been
      saved on little-endian machines from the ones saved on big-endian
      machines, and to heuristically identify pcap files.

   Major Version (16 bits):  an unsigned value, giving the number of the
      current major version of the format.  The value for the current
      version of the format is 2.  This value should change if the
      format changes in such a way that code that reads the new format
      could not read the old format (i.e., code to read both formats
      would have to check the version number and use different code
      paths for the two formats) and code that reads the old format
      could not read the new format.

   Minor Version (16 bits):  an unsigned value, giving the number of the







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      current minor version of the format.  The value is for the current
      version of the format is 4.  This value should change if the
      format changes in such a way that code that reads the new format
      could read the old format without checking the version number but
      code that reads the old format could not read all files in the new
      format.

   Reserved1 (32 bits):  not used - SHOULD be filled with 0 by pcap file
      writers, and MUST be ignored by pcap file readers.  This value was
      documented by some older implementations as "gmt to local
      correction".  Some older pcap file writers stored non-zero values
      in this field.

   Reserved2 (32 bits):  not used - SHOULD be filled with 0 by pcap file
      writers, and MUST be ignored by pcap file readers.  This value was
      documented by some older implementations as "accuracy of
      timestamps".  Some older pcap file writers stored non-zero values
      in this field.

   SnapLen (32 bits):  an unsigned value indicating the maximum number
      of octets captured from each packet.  The portion of each packet
      that exceeds this value will not be stored in the file.  This
      value MUST NOT be zero; if no limit was specified, the value
      should be a number greater than or equal to the largest packet
      length in the file.

   LinkType (16 bits):  a 16-bit unsigned value that defines the link
      layer type of packets in the file.  This field is defined in the
      Section 8.2 IANA registry.

   Frame Cyclic Sequence (FCS) present (4 bits):  if the "f" bit is set,
      then the 3 FCS bits provide the number of 16-bit (2 byte) words of
      FCS that are appended to each packet.

      valid values are between 0 and 7, with ethernet typically having a
      length of 4 bytes, or a value of 2.

   The bits marked as zero MUST be set to zero by pcap writers, and MUST
   be ignored by pcap readers.

5.  Packet Record

   A Packet Record is the standard container for storing the packets
   coming from the network.







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                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     0 |                      Timestamp (Seconds)                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     4 |            Timestamp (Microseconds or nanoseconds)            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     8 |                    Captured Packet Length                     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    12 |                    Original Packet Length                     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    16 /                                                               /
       /                          Packet Data                          /
       /                        variable length                        /
       /                                                               /
       +---------------------------------------------------------------+

                        Figure 2: Packet Record

   The Packet Header length is 16 octets.

   The meaning of the fields in the Packet Record is:

   Timestamp (Seconds) and Timestamp (Microseconds or nanoseconds):  sec
      onds and fraction of a seconds values of a timestamp.

      The seconds value is a 32-bit unsigned integer that represents the
      number of seconds that have elapsed since 1970-01-01 00:00:00 UTC,
      and the microseconds or nanoseconds value represents the number of
      microseconds or nanoseconds that have elapsed since that seconds.

      Whether the value represents microseconds or nanoseconds is
      specified by the magic number in the File Header.

   Captured Packet Length (32 bits):  an unsigned value that indicates
      the number of octets captured from the packet (i.e. the length of
      the Packet Data field).  It will be the minimum value among the
      Original Packet Length and the snapshot length for the interface
      (SnapLen, defined in Figure 1).

   Original Packet Length (32 bits):  an unsigned value that indicates
      the actual length of the packet when it was transmitted on the
      network.  It can be different from the Captured Packet Length if
      the packet has been truncated by the capture process.

   Packet Data:  the data coming from the network, including link-layer





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      headers.  The actual length of this field is Captured Packet
      Length.  The format of the link-layer headers depends on the
      LinkType field specified in the file header (see Figure 1) and it
      is specified in the entry for that format in [LINKTYPES].

6.  Recommended File Name Extension: .pcap

   The recommended file name extension for the "PCAP Capture File
   Format" specified in this document is ".pcap".

   On Windows and macOS, files are distinguished by an extension to
   their filename.  Such an extension is technically not actually
   required, as applications should be able to automatically detect the
   pcap file format through the "magic bytes" at the beginning of the
   file, as some other UN*X desktop environments do.  However, using
   name extensions makes it easier to work with files (e.g. visually
   distinguish file formats) so it is recommended - though not required
   - to use .pcap as the name extension for files following this
   specification.

   Please note: To avoid confusion (such as the current usage of .cap
   for a plethora of different capture file formats) file name
   extensions other than .pcap should be avoided.

   There is new work to create the PCAP Next Generation capture File
   Format (see [I-D.tuexen-opsawg-pcapng]).  The new file format is not
   compatible with this specification, but many programs read both
   transparently.  Files of that type will usually start with a
   Section Header Block, with a magic number of 0x0A0D0D0A.

7.  Security Considerations

   TBD.

8.  IANA Considerations

   This document requires the following IANA actions:

8.1.  Media-Type Registry

   This section registers the the 'application/pcap' in the "Media
   Types" registry.  These media types are used to indicate that the
   content is packet capture as described in this document.

8.1.1.  application/pcap






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    Type name:  application
    Subtype name:  pcap
    Required parameters:  none
    Optional parameters:  none
    Encoding considerations:  PCAP files contain network packets
    Security considerations:  See Security Considerations, Section
    Interoperability considerations:  The format is designed to be broadly interoperable.
    Published specification:  THIS RFC.
    Applications that use this media type: tcpdump, wireshark, others.
    Additional information:
      Magic number(s): 0xA1B2C3D4, and 0xA1B23C4D in both endian orders
      File extension(s):  .pcap
      Macintosh file type code(s):  none
    Person & email address to contact for further information: The Tcpdump Group, www.tcpdump.org
    Intended usage:  LIMITED
    Restrictions on usage:  NONE
    Author:  Guy Harris and Michael Richardson
    Change controller:  The Tcpdump Group
    Provisional registration? (standards tree only):  NO

8.2.  LinkType Registry

   IANA is requested to create a new Registry entitled: "The PCAP
   Registry", and within that Registry to create a table called: "PCAP
   LinkType List".

   The LinkType Registry is a table of 16-bit numbers.  The Registry has
   three sections with different [RFC8126] rules:

   *  values from 0 to 32767 are marked as Specification Required.

   *  values from 32768 to 65000 are marked as First-Come First-Served.

   *  values from 65000 to 65535 are marked as Private Use.

   The Registry has four columns: the symbolic name
   (LINKTYPE_something), the integer value, a very short description,
   and the document/requestor reference.

   The Registry shall be populated as follows in the table below.  In
   each case here, the reference should be http://www.tcpdump.org/
   linktypes.html, which is not repeated.

   The initial value of table is base upon the Link type list maintained
   by libpcap, and published on the tcpdump.org web site as
   http://www.tcpdump.org/linktypes.html.





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   There is often an associated DLT value which are often identical in
   value, but not universally so.  DLT values are associated with
   specific operation system captures, and are operating system
   specific.

   +=====================================+========+====================+
   | LINKTYPE name                       |LINKTYPE|description         |
   |                                     | value  |                    |
   +=====================================+========+====================+
   | LINKTYPE_NULL                       |   0    |BSD loopback        |
   |                                     |        |encapsulation       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ETHERNET                   |   1    |IEEE 802.3 Ethernet |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_EXP_ETHERNET               |   2    |Xerox experimental  |
   |                                     |        |3Mb Ethernet        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_AX25                       |   3    |AX.25 packet        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PRONET                     |   4    |Reserved for PRONET |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_CHAOS                      |   5    |Reserved for MIT    |
   |                                     |        |CHAOSNET            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_5                  |   6    |IEEE 802.5 Token    |
   |                                     |        |Ring                |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ARCNET_BSD                 |   7    |ARCNET Data Packets |
   |                                     |        |with BSD            |
   |                                     |        |encapsulation       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SLIP                       |   8    |SLIP, w/            |
   |                                     |        |LINKTYPE_SLIP       |
   |                                     |        |header.             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PPP                        |   9    |PPP, as per RFC     |
   |                                     |        |1661/RFC 1662       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_FDDI                       |   10   |FDDI: per ANSI      |
   |                                     |        |INCITS 239-1994.    |
   +-------------------------------------+--------+--------------------+
   | not to be used                      | 11-49  |Do not use these    |
   |                                     |        |values              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PPP_HDLC                   |   50   |PPP in HDLC-like    |
   |                                     |        |framing, as per RFC |
   |                                     |        |1662                |
   +-------------------------------------+--------+--------------------+



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   | LINKTYPE_PPP_ETHER                  |   51   |PPPoE; per RFC 2516 |
   +-------------------------------------+--------+--------------------+
   | not to be used                      | 52-98  |Do not use these    |
   |                                     |        |values              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SYMANTEC_FIREWALL          |   99   |Reserved for        |
   |                                     |        |Symantec Enterprise |
   |                                     |        |Firewall            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ATM_RFC1483                |  100   |RFC 1483 LLC/SNAP-  |
   |                                     |        |encapsulated ATM    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RAW                        |  101   |Raw IP; begins with |
   |                                     |        |an IPv4 or IPv6     |
   |                                     |        |header              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SLIP_BSDOS                 |  102   |Reserved for BSD/OS |
   |                                     |        |SLIP BPF header     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PPP_BSDOS                  |  103   |Reserved for BSD/OS |
   |                                     |        |PPP BPF header      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_C_HDLC                     |  104   |Cisco PPP with HDLC |
   |                                     |        |framing, as per     |
   |                                     |        |section 4.3.1 of RFC|
   |                                     |        |1547                |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_11                 |  105   |IEEE 802.11 wireless|
   |                                     |        |LAN.                |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ATM_CLIP                   |  106   |ATM Classical IP,   |
   |                                     |        |with no header      |
   |                                     |        |preceding IP        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_FRELAY                     |  107   |Frame Relay LAPF    |
   |                                     |        |frames              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LOOP                       |  108   |OpenBSD loopback    |
   |                                     |        |encapsulation       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ENC                        |  109   |Reserved for OpenBSD|
   |                                     |        |IPSEC encapsulation |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LANE8023                   |  110   |Reserved for ATM    |
   |                                     |        |LANE + 802.3        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_HIPPI                      |  111   |Reserved for NetBSD |
   |                                     |        |HIPPI               |



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   +-------------------------------------+--------+--------------------+
   | LINKTYPE_HDLC                       |  112   |Reserved for NetBSD |
   |                                     |        |HDLC framing        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LINUX_SLL                  |  113   |Linux "cooked"      |
   |                                     |        |capture             |
   |                                     |        |encapsulation       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LTALK                      |  114   |Apple LocalTalk     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ECONET                     |  115   |Reserved for Acorn  |
   |                                     |        |Econet              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IPFILTER                   |  116   |Reserved for OpenBSD|
   |                                     |        |ipfilter            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PFLOG                      |  117   |OpenBSD pflog;      |
   |                                     |        |"struct pfloghdr"   |
   |                                     |        |structure           |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_CISCO_IOS                  |  118   |Reserved for Cisco- |
   |                                     |        |internal use        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_11_PRISM           |  119   |Prism monitor mode  |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_11_AIRONET         |  120   |Reserved for 802.11 |
   |                                     |        |+ FreeFreeBSD       |
   |                                     |        |Aironet radio       |
   |                                     |        |metadata            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_HHDLC                      |  121   |Reserved for Siemens|
   |                                     |        |HiPath HDLC         |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IP_OVER_FC                 |  122   |RFC 2625 IP-over-   |
   |                                     |        |Fibre Channel       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SUNATM                     |  123   |ATM traffic, / per  |
   |                                     |        |SunATM devices      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RIO                        |  124   |Reserved for RapidIO|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PCI_EXP                    |  125   |Reserved for PCI    |
   |                                     |        |Express             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_AURORA                     |  126   |Reserved for Xilinx |
   |                                     |        |Aurora link layer   |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_11_RADIOTAP        |  127   |Radiotap            |



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   |                                     |        |header[Radiotap],   |
   |                                     |        |followed by an      |
   |                                     |        |802.11 header       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_TZSP                       |  128   |Reserved for Tazmen |
   |                                     |        |Sniffer Protocol    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ARCNET_LINUX               |  129   |ARCNET Data Packets,|
   |                                     |        |per RFC 1051 frames |
   |                                     |        |w/variations        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_MLPPP              |  130   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_MLFR               |  131   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_ES                 |  132   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_GGSN               |  133   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_MFR                |  134   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_ATM2               |  135   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_SERVICES           |  136   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_ATM1               |  137   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_APPLE_IP_OVER_IEEE1394     |  138   |Apple IP-over-IEEE  |
   |                                     |        |1394 cooked header  |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_MTP2_WITH_PHDR             |  139   |Signaling System 7  |
   |                                     |        |(SS7) Message       |
   |                                     |        |Transfer Part Level |
   |                                     |        |ITU-T Q.703         |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_MTP2                       |  140   |SS7 Level 2, Q.703  |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_MTP3                       |  141   |SS7 Level 3, Q.704  |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SCCP                       |  142   |SS7 Control Part,   |



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   |                                     |        |ITU-T               |
   |                                     |        |Q.711/Q.712/Q.713/  |
   |                                     |        |Q.714               |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DOCSIS                     |  143   |DOCSIS MAC frames,  |
   |                                     |        |DOCSIS 3.1          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LINUX_IRDA                 |  144   |Linux-IrDA packets  |
   |                                     |        |w/                  |
   |                                     |        |LINKTYPE_LINUX_IRDA |
   |                                     |        |header              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IBM_SP                     |  145   |Reserved for IBM SP |
   |                                     |        |switch              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IBM_SN                     |  146   |Reserved for IBM    |
   |                                     |        |Next Federation     |
   |                                     |        |switch              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_01                |  147   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_02                |  148   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_03                |  149   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_04                |  150   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_05                |  151   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_06                |  152   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_07                |  153   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_08                |  154   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_09                |  155   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_10                |  156   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_11                |  157   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_12                |  158   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_13                |  159   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_14                |  160   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_15                |  161   |For private use     |



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   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RESERVED_16                |  162   |For private use     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_11_AVS             |  163   |AVS header[AVS],    |
   |                                     |        |followed by an      |
   |                                     |        |802.11 header       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_MONITOR            |  164   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_BACNET_MS_TP               |  165   |BACnet MS/TP frames,|
   |                                     |        |per 9.3 MS/TP Frame |
   |                                     |        |Format ANSI 135     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PPP_PPPD                   |  166   |PPP in HDLC-like    |
   |                                     |        |encapsulation, like |
   |                                     |        |LINKTYPE_PPP_HDLC,  |
   |                                     |        |different stuffing  |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_PPPOE              |  167   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_PPPOE_ATM          |  168   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_GPRS_LLC                   |  169   |General Packet Radio|
   |                                     |        |Service Logical Link|
   |                                     |        |Control, as per 3GPP|
   |                                     |        |TS 04.64            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_GPF_T                      |  170   |Transparent-mapped  |
   |                                     |        |generic framing     |
   |                                     |        |procedure, as       |
   |                                     |        |specified by ITU-T  |
   |                                     |        |Recommendation      |
   |                                     |        |G.7041/Y.1303       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_GPF_F                      |  171   |Frame-mapped generic|
   |                                     |        |framing procedure,  |
   |                                     |        |as specified by     |
   |                                     |        |ITU-T Recommendation|
   |                                     |        |G.7041/Y.1303       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_GCOM_T1E1                  |  172   |Reserved for Gcom   |
   |                                     |        |T1/E1 line          |
   |                                     |        |monitoring equipment|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_GCOM_SERIAL                |  173   |Reserved for Gcom   |



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   |                                     |        |T1/E1 line          |
   |                                     |        |monitoring equipment|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_PIC_PEER           |  174   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ERF_ETH                    |  175   |Endace ERF header   |
   |                                     |        |followed by 802.3   |
   |                                     |        |Ethernet            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ERF_POS                    |  176   |Endace ERF header   |
   |                                     |        |followed by Packet- |
   |                                     |        |over-SONET          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LINUX_LAPD                 |  177   |Link Access         |
   |                                     |        |Procedures on the D |
   |                                     |        |Channel (LAPD)      |
   |                                     |        |frames, as specified|
   |                                     |        |by ITU-T            |
   |                                     |        |Recommendation Q.920|
   |                                     |        |and ITU-T           |
   |                                     |        |Recommendation Q.921|
   |                                     |        |, captured via      |
   |                                     |        |vISDN, with a       |
   |                                     |        |LINKTYPE_LINUX_LAPD |
   |                                     |        |header , followed by|
   |                                     |        |the Q.921 frame,    |
   |                                     |        |starting with the   |
   |                                     |        |address field.      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_ETHER              |  178   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_PPP                |  179   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_FRELAY             |  180   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_CHDLC              |  181   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_MFR                        |  182   |FRF.16.1 Multi-Link |
   |                                     |        |Frame Relay frames, |
   |                                     |        |beginning with an   |
   |                                     |        |FRF.12 Interface    |
   |                                     |        |fragmentation format|
   |                                     |        |fragmentation       |



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   |                                     |        |header.             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_VP                 |  182   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_A653_ICM                   |  185   |Reserved for Arinc  |
   |                                     |        |653 Interpartition  |
   |                                     |        |Communication       |
   |                                     |        |messages            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_USB_FREEBSD                |  186   |USB packets,        |
   |                                     |        |beginning with a    |
   |                                     |        |FreeBSD USB header  |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_BLUETOOTH_HCI_H4           |  187   |Bluetooth HCI UART  |
   |                                     |        |transport layer; the|
   |                                     |        |frame contains an   |
   |                                     |        |HCI packet indicator|
   |                                     |        |byte, as specified  |
   |                                     |        |by the UART         |
   |                                     |        |Transport Layer     |
   |                                     |        |portion of the most |
   |                                     |        |recent Bluetooth    |
   |                                     |        |Core specification ,|
   |                                     |        |followed by an HCI  |
   |                                     |        |packet of the       |
   |                                     |        |specified packet    |
   |                                     |        |type, as specified  |
   |                                     |        |by the Host         |
   |                                     |        |Controller Interface|
   |                                     |        |Functional          |
   |                                     |        |Specification       |
   |                                     |        |portion of the most |
   |                                     |        |recent Bluetooth    |
   |                                     |        |Core Specification. |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_16_MAC_CPS         |  188   |Reserved for IEEE   |
   |                                     |        |802.16 MAC Common   |
   |                                     |        |Part Sublayer       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_USB_LINUX                  |  189   |USB packets,        |
   |                                     |        |beginning with a    |
   |                                     |        |Linux USB header, as|
   |                                     |        |specified by the    |
   |                                     |        |struct usbmon_packet|
   |                                     |        |in the              |
   |                                     |        |Documentation/usb/  |
   |                                     |        |usbmon.txt file in  |



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   |                                     |        |the Linux source    |
   |                                     |        |tree.  Only the     |
   |                                     |        |first 48 bytes of   |
   |                                     |        |that header are     |
   |                                     |        |present.  All fields|
   |                                     |        |in the header are in|
   |                                     |        |host byte order.    |
   |                                     |        |When performing a   |
   |                                     |        |live capture, the   |
   |                                     |        |host byte order is  |
   |                                     |        |the byte order of   |
   |                                     |        |the machine on which|
   |                                     |        |the packets are     |
   |                                     |        |captured.  When     |
   |                                     |        |reading a pcap file,|
   |                                     |        |the byte order is   |
   |                                     |        |the byte order for  |
   |                                     |        |the file, as        |
   |                                     |        |specified by the    |
   |                                     |        |file's magic number;|
   |                                     |        |when reading a      |
   |                                     |        |pcapng file, the    |
   |                                     |        |byte order is the   |
   |                                     |        |byte order for the  |
   |                                     |        |section of the      |
   |                                     |        |pcapng file, as     |
   |                                     |        |specified by the    |
   |                                     |        |Section Header      |
   |                                     |        |Block.              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_CAN20B                     |  190   |Reserved for        |
   |                                     |        |Controller Area     |
   |                                     |        |Network (CAN) v.    |
   |                                     |        |2.0B packets        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_15_4_LINUX         |  191   |IEEE 802.15.4, with |
   |                                     |        |address fields      |
   |                                     |        |padded, as is done  |
   |                                     |        |by Linux drivers    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PPI                        |  192   |Per-Packet          |
   |                                     |        |Information         |
   |                                     |        |information, as     |
   |                                     |        |specified by the    |
   |                                     |        |Per-Packet          |
   |                                     |        |Information Header  |
   |                                     |        |Specification ,     |
   |                                     |        |followed by a packet|



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   |                                     |        |with the LINKTYPE_  |
   |                                     |        |value specified by  |
   |                                     |        |the pph_dlt field of|
   |                                     |        |that header.        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_16_MAC_CPS_RADIO   |  193   |Reserved for 802.16 |
   |                                     |        |MAC Common Part     |
   |                                     |        |Sublayer plus radio |
   |                                     |        |header              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_ISM                |  194   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_15_4_WITHFCS       |  195   |IEEE 802.15.4 Low-  |
   |                                     |        |Rate Wireless       |
   |                                     |        |Networks, with each |
   |                                     |        |packet having the   |
   |                                     |        |FCS at the end of   |
   |                                     |        |the frame.          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SITA                       |  196   |Various link-layer  |
   |                                     |        |types, with a       |
   |                                     |        |pseudo-header , for |
   |                                     |        |SITA                |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ERF                        |  197   |Various link-layer  |
   |                                     |        |types, with a       |
   |                                     |        |pseudo-header, for  |
   |                                     |        |Endace DAG cards;   |
   |                                     |        |encapsulates Endace |
   |                                     |        |ERF records.        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RAIF1                      |  198   |Reserved for        |
   |                                     |        |Ethernet packets    |
   |                                     |        |captured from a u10 |
   |                                     |        |Networks board      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IPMB_KONTRON               |  199   |Reserved for IPMB   |
   |                                     |        |packet for IPMI,    |
   |                                     |        |with a 2-byte header|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_ST                 |  200   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_BLUETOOTH_HCI_H4_WITH_PHDR |  201   |Bluetooth HCI UART  |
   |                                     |        |transport layer; the|
   |                                     |        |frame contains a    |
   |                                     |        |4-byte direction    |



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   |                                     |        |field, in network   |
   |                                     |        |byte order (big-    |
   |                                     |        |endian), the low-   |
   |                                     |        |order bit of which  |
   |                                     |        |is set if the frame |
   |                                     |        |was sent from the   |
   |                                     |        |host to the         |
   |                                     |        |controller and clear|
   |                                     |        |if the frame was    |
   |                                     |        |received by the host|
   |                                     |        |from the controller,|
   |                                     |        |followed by an HCI  |
   |                                     |        |packet indicator    |
   |                                     |        |byte, as specified  |
   |                                     |        |by the UART         |
   |                                     |        |Transport Layer     |
   |                                     |        |portion of the most |
   |                                     |        |recent Bluetooth    |
   |                                     |        |Core specification ,|
   |                                     |        |followed by an HCI  |
   |                                     |        |packet of the       |
   |                                     |        |specified packet    |
   |                                     |        |type, as specified  |
   |                                     |        |by the Host         |
   |                                     |        |Controller Interface|
   |                                     |        |Functional          |
   |                                     |        |Specification       |
   |                                     |        |portion of the most |
   |                                     |        |recent Bluetooth    |
   |                                     |        |Core Specification. |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_AX25_KISS                  |  202   |AX.25 packet, with a|
   |                                     |        |1-byte KISS header  |
   |                                     |        |containing a type   |
   |                                     |        |indicator.          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LAPD                       |  203   |Link Access         |
   |                                     |        |Procedures on the D |
   |                                     |        |Channel (LAPD)      |
   |                                     |        |frames, as specified|
   |                                     |        |by ITU-T            |
   |                                     |        |Recommendation Q.920|
   |                                     |        |and ITU-T           |
   |                                     |        |Recommendation Q.921|
   |                                     |        |, starting with the |
   |                                     |        |address field, with |
   |                                     |        |no pseudo-header.   |
   +-------------------------------------+--------+--------------------+



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   | LINKTYPE_PPP_WITH_DIR               |  204   |PPP, as per RFC 1661|
   |                                     |        |and RFC 1662 ,      |
   |                                     |        |preceded with a one-|
   |                                     |        |byte pseudo-header  |
   |                                     |        |with a zero value   |
   |                                     |        |meaning received by |
   |                                     |        |this host and a non-|
   |                                     |        |zero value meaning  |
   |                                     |        |sent by this host;  |
   |                                     |        |if the first 2 bytes|
   |                                     |        |are 0xff and 0x03,  |
   |                                     |        |it's PPP in HDLC-   |
   |                                     |        |like framing, with  |
   |                                     |        |the PPP header      |
   |                                     |        |following those two |
   |                                     |        |bytes, otherwise    |
   |                                     |        |it's PPP without    |
   |                                     |        |framing, and the    |
   |                                     |        |packet begins with  |
   |                                     |        |the PPP header.  The|
   |                                     |        |data in the frame is|
   |                                     |        |not octet-stuffed or|
   |                                     |        |bit-stuffed.        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_C_HDLC_WITH_DIR            |  205   |Cisco PPP with HDLC |
   |                                     |        |framing, as per     |
   |                                     |        |section 4.3.1 of RFC|
   |                                     |        |1547 , preceded with|
   |                                     |        |a one-byte pseudo-  |
   |                                     |        |header with a zero  |
   |                                     |        |value meaning       |
   |                                     |        |received by this    |
   |                                     |        |host and a non-zero |
   |                                     |        |value meaning sent  |
   |                                     |        |by this host.       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_FRELAY_WITH_DIR            |  206   |Frame Relay LAPF    |
   |                                     |        |frames, beginning   |
   |                                     |        |with a one-byte     |
   |                                     |        |pseudo-header with a|
   |                                     |        |zero value meaning  |
   |                                     |        |received by this    |
   |                                     |        |host (DCE->DTE) and |
   |                                     |        |a non-zero value    |
   |                                     |        |meaning sent by this|
   |                                     |        |host (DTE->DCE),    |
   |                                     |        |followed by an ITU-T|
   |                                     |        |Recommendation Q.922|



Harris & Richardson     Expires 25 December 2021               [Page 20]


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   |                                     |        |LAPF header starting|
   |                                     |        |with the address    |
   |                                     |        |field, and without  |
   |                                     |        |an FCS at the end of|
   |                                     |        |the frame.          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LAPB_WITH_DIR              |  207   |Link Access         |
   |                                     |        |Procedure, Balanced |
   |                                     |        |(LAPB), as specified|
   |                                     |        |by ITU-T            |
   |                                     |        |Recommendation X.25 |
   |                                     |        |, preceded with a   |
   |                                     |        |one-byte pseudo-    |
   |                                     |        |header with a zero  |
   |                                     |        |value meaning       |
   |                                     |        |received by this    |
   |                                     |        |host (DCE->DTE) and |
   |                                     |        |a non-zero value    |
   |                                     |        |meaning sent by this|
   |                                     |        |host (DTE->DCE).    |
   +-------------------------------------+--------+--------------------+
   | Reserved                            |  208   |Reserved for an     |
   |                                     |        |unspecified link-   |
   |                                     |        |layer type          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IPMB_LINUX                 |  209   |IPMB over an I2C    |
   |                                     |        |circuit, with a     |
   |                                     |        |Linux-specific      |
   |                                     |        |pseudo-header       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_FLEXRAY                    |  210   |Reserved for FlexRay|
   |                                     |        |automotive bus      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_MOST                       |  211   |Reserved for Media  |
   |                                     |        |Oriented Systems    |
   |                                     |        |Transport (MOST) bus|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LIN                        |  212   |Reserved for Local  |
   |                                     |        |Interconnect Network|
   |                                     |        |(LIN) bus for       |
   |                                     |        |vehicle networks    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_X2E_SERIAL                 |  213   |Reserved for X2E    |
   |                                     |        |serial line captures|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_X2E_XORAYA                 |  214   |Reserved for X2E    |
   |                                     |        |Xoraya data loggers |
   +-------------------------------------+--------+--------------------+



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   | LINKTYPE_IEEE802_15_4_NONASK_PHY    |  215   |IEEE 802.15.4 Low-  |
   |                                     |        |Rate Wireless       |
   |                                     |        |Networks, with each |
   |                                     |        |packet having the   |
   |                                     |        |FCS at the end of   |
   |                                     |        |the frame, and with |
   |                                     |        |the PHY-level data  |
   |                                     |        |for the O-QPSK,     |
   |                                     |        |BPSK, GFSK, MSK, and|
   |                                     |        |RCC DSS BPSK PHYs (4|
   |                                     |        |octets of 0 as      |
   |                                     |        |preamble, one octet |
   |                                     |        |of SFD, one octet of|
   |                                     |        |frame length +      |
   |                                     |        |reserved bit)       |
   |                                     |        |preceding the MAC-  |
   |                                     |        |layer data (starting|
   |                                     |        |with the frame      |
   |                                     |        |control field).     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LINUX_EVDEV                |  216   |Reserved for Linux  |
   |                                     |        |evdev messages      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_GSMTAP_UM                  |  217   |Reserved for GSM Um |
   |                                     |        |interface, with     |
   |                                     |        |gsmtap header       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_GSMTAP_ABIS                |  218   |Reserved for GSM    |
   |                                     |        |Abis interface, with|
   |                                     |        |gsmtap header       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_MPLS                       |  219   |MPLS packets with   |
   |                                     |        |MPLS label as the   |
   |                                     |        |header              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_USB_LINUX_MMAPPED          |  220   |USB packets,        |
   |                                     |        |beginning with a    |
   |                                     |        |Linux USB header, as|
   |                                     |        |specified by the    |
   |                                     |        |struct usbmon_packet|
   |                                     |        |in the              |
   |                                     |        |Documentation/usb/  |
   |                                     |        |usbmon.txt file in  |
   |                                     |        |the Linux source    |
   |                                     |        |tree.  All 64 bytes |
   |                                     |        |of the header are   |
   |                                     |        |present.  All fields|
   |                                     |        |in the header are in|



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   |                                     |        |host byte order.    |
   |                                     |        |When performing a   |
   |                                     |        |live capture, the   |
   |                                     |        |host byte order is  |
   |                                     |        |the byte order of   |
   |                                     |        |the machine on which|
   |                                     |        |the packets are     |
   |                                     |        |captured.  When     |
   |                                     |        |reading a pcap file,|
   |                                     |        |the byte order is   |
   |                                     |        |the byte order for  |
   |                                     |        |the file, as        |
   |                                     |        |specified by the    |
   |                                     |        |file's magic number;|
   |                                     |        |when reading a      |
   |                                     |        |pcapng file, the    |
   |                                     |        |byte order is the   |
   |                                     |        |byte order for the  |
   |                                     |        |section of the      |
   |                                     |        |pcapng file, as     |
   |                                     |        |specified by the    |
   |                                     |        |Section Header      |
   |                                     |        |Block.  For         |
   |                                     |        |isochronous         |
   |                                     |        |transfers, the ndesc|
   |                                     |        |field specifies the |
   |                                     |        |number of           |
   |                                     |        |isochronous         |
   |                                     |        |descriptors that    |
   |                                     |        |follow.             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DECT                       |  221   |Reserved for DECT   |
   |                                     |        |packets, with a     |
   |                                     |        |pseudo-header       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_AOS                        |  222   |Reserved for OS     |
   |                                     |        |Space Data Link     |
   |                                     |        |Protocol            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_WIHART                     |  223   |Reserved for        |
   |                                     |        |Wireless HART       |
   |                                     |        |(Highway Addressable|
   |                                     |        |Remote Transducer)  |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_FC_2                       |  224   |Fibre Channel FC-2  |
   |                                     |        |frames, beginning   |
   |                                     |        |with a Frame_Header.|
   +-------------------------------------+--------+--------------------+



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   | LINKTYPE_FC_2_WITH_FRAME_DELIMS     |  225   |Fibre Channel FC-2  |
   |                                     |        |frames, beginning an|
   |                                     |        |encoding of the SOF,|
   |                                     |        |followed by a       |
   |                                     |        |Frame_Header, and   |
   |                                     |        |ending with an      |
   |                                     |        |encoding of the SOF.|
   |                                     |        |The encodings       |
   |                                     |        |represent the frame |
   |                                     |        |delimiters as 4-byte|
   |                                     |        |sequences           |
   |                                     |        |representing the    |
   |                                     |        |corresponding       |
   |                                     |        |ordered sets, with  |
   |                                     |        |K28.5 represented as|
   |                                     |        |0xBC, and the D     |
   |                                     |        |symbols as the      |
   |                                     |        |corresponding byte  |
   |                                     |        |values; for example,|
   |                                     |        |SOFi2, which is     |
   |                                     |        |K28.5 - D21.5 - D1.2|
   |                                     |        |- D21.2, is         |
   |                                     |        |represented as 0xBC |
   |                                     |        |0xB5 0x55 0x55.     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IPNET                      |  226   |Solaris ipnet       |
   |                                     |        |pseudo-header ,     |
   |                                     |        |followed by an IPv4 |
   |                                     |        |or IPv6 datagram.   |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_CAN_SOCKETCAN              |  227   |CAN (Controller Area|
   |                                     |        |Network) frames,    |
   |                                     |        |with a pseudo-header|
   |                                     |        |followed by the     |
   |                                     |        |frame payload.      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IPV4                       |  228   |Raw IPv4; the packet|
   |                                     |        |begins with an IPv4 |
   |                                     |        |header.             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IPV6                       |  229   |Raw IPv6; the packet|
   |                                     |        |begins with an IPv6 |
   |                                     |        |header.             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_15_4_NOFCS         |  230   |IEEE 802.15.4 Low-  |
   |                                     |        |Rate Wireless       |
   |                                     |        |Network, without the|
   |                                     |        |FCS at the end of   |



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   |                                     |        |the frame.          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DBUS                       |  231   |Raw D-Bus messages ,|
   |                                     |        |starting with the   |
   |                                     |        |endianness flag,    |
   |                                     |        |followed by the     |
   |                                     |        |message type, etc., |
   |                                     |        |but without the     |
   |                                     |        |authentication      |
   |                                     |        |handshake before the|
   |                                     |        |message sequence.   |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_VS                 |  232   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_SRX_E2E            |  233   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_FIBRECHANNEL       |  234   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DVB_CI                     |  235   |DVB-CI (DVB Common  |
   |                                     |        |Interface for       |
   |                                     |        |communication       |
   |                                     |        |between a PC Card   |
   |                                     |        |module and a DVB    |
   |                                     |        |receiver), with the |
   |                                     |        |message format      |
   |                                     |        |specified by the    |
   |                                     |        |PCAP format for DVB-|
   |                                     |        |CI specification    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_MUX27010                   |  236   |Variant of 3GPP TS  |
   |                                     |        |27.010 multiplexing |
   |                                     |        |protocol (similar   |
   |                                     |        |to, but not the same|
   |                                     |        |as, 27.010).        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_STANAG_5066_D_PDU          |  237   |D_PDUs as described |
   |                                     |        |by NATO standard    |
   |                                     |        |STANAG 5066,        |
   |                                     |        |starting with the   |
   |                                     |        |synchronization     |
   |                                     |        |sequence, and       |
   |                                     |        |including both      |
   |                                     |        |header and data     |
   |                                     |        |CRCs.  The current  |
   |                                     |        |version of STANAG   |



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   |                                     |        |5066 is backwards-  |
   |                                     |        |compatible with the |
   |                                     |        |1.0.2 version ,     |
   |                                     |        |although newer      |
   |                                     |        |versions are        |
   |                                     |        |classified.         |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_JUNIPER_ATM_CEMIC          |  238   |Reserved for Juniper|
   |                                     |        |Networks            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_NFLOG                      |  239   |Linux netlink       |
   |                                     |        |NETLINK NFLOG socket|
   |                                     |        |log messages.       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_NETANALYZER                |  240   |Pseudo-header for   |
   |                                     |        |Hilscher            |
   |                                     |        |Gesellschaft fuer   |
   |                                     |        |Systemautomation mbH|
   |                                     |        |netANALYZER devices |
   |                                     |        |, followed by an    |
   |                                     |        |Ethernet frame,     |
   |                                     |        |beginning with the  |
   |                                     |        |MAC header and      |
   |                                     |        |ending with the FCS.|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_NETANALYZER_TRANSPARENT    |  241   |Pseudo-header for   |
   |                                     |        |Hilscher            |
   |                                     |        |Gesellschaft fuer   |
   |                                     |        |Systemautomation mbH|
   |                                     |        |netANALYZER devices |
   |                                     |        |, followed by an    |
   |                                     |        |Ethernet frame,     |
   |                                     |        |beginning with the  |
   |                                     |        |preamble, SFD, and  |
   |                                     |        |MAC header, and     |
   |                                     |        |ending with the FCS.|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IPOIB                      |  242   |IP-over-InfiniBand, |
   |                                     |        |as specified by RFC |
   |                                     |        |4391 section 6      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_MPEG_2_TS                  |  243   |MPEG-2 Transport    |
   |                                     |        |Stream transport    |
   |                                     |        |packets, as         |
   |                                     |        |specified by ISO    |
   |                                     |        |13818-1/ ITU-T      |
   |                                     |        |Recommendation      |
   |                                     |        |H.222.0 (see table  |



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   |                                     |        |2-2 of section      |
   |                                     |        |2.4.3.2 Transport   |
   |                                     |        |Stream packet       |
   |                                     |        |layer).             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_NG40                       |  244   |Pseudo-header for   |
   |                                     |        |ng4T GmbH's UMTS    |
   |                                     |        |Iub/Iur-over-ATM and|
   |                                     |        |Iub/Iur-over-IP     |
   |                                     |        |format as used by   |
   |                                     |        |their ng40 protocol |
   |                                     |        |tester , followed by|
   |                                     |        |frames for the Frame|
   |                                     |        |Protocol as         |
   |                                     |        |specified by 3GPP TS|
   |                                     |        |25.427 for dedicated|
   |                                     |        |channels and 3GPP TS|
   |                                     |        |25.435 for common/  |
   |                                     |        |shared channels in  |
   |                                     |        |the case of ATM AAL2|
   |                                     |        |or UDP traffic, by  |
   |                                     |        |SSCOP packets as    |
   |                                     |        |specified by ITU-T  |
   |                                     |        |Recommendation      |
   |                                     |        |Q.2110 for ATM AAL5 |
   |                                     |        |traffic, and by NBAP|
   |                                     |        |packets for SCTP    |
   |                                     |        |traffic.            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_NFC_LLCP                   |  245   |Pseudo-header for   |
   |                                     |        |NFC LLCP packet     |
   |                                     |        |captures , followed |
   |                                     |        |by frame data for   |
   |                                     |        |the LLCP Protocol as|
   |                                     |        |specified by        |
   |                                     |        |NFCForum-TS-LLCP_1.1|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PFSYNC                     |  246   |Reserved for pfsync |
   |                                     |        |output              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_INFINIBAND                 |  247   |Raw InfiniBand      |
   |                                     |        |frames, starting    |
   |                                     |        |with the Local      |
   |                                     |        |Routing Header, as  |
   |                                     |        |specified in Chapter|
   |                                     |        |5 Data packet format|
   |                                     |        |of InfiniBand[TM]   |
   |                                     |        |Architectural       |



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   |                                     |        |Specification       |
   |                                     |        |Release 1.2.1 Volume|
   |                                     |        |1 - General         |
   |                                     |        |Specifications      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SCTP                       |  248   |SCTP packets, as    |
   |                                     |        |defined by RFC 4960 |
   |                                     |        |, with no lower-    |
   |                                     |        |level protocols such|
   |                                     |        |as IPv4 or IPv6.    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_USBPCAP                    |  249   |USB packets,        |
   |                                     |        |beginning with a    |
   |                                     |        |USBPcap header      |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RTAC_SERIAL                |  250   |Serial-line packet  |
   |                                     |        |header for the      |
   |                                     |        |Schweitzer          |
   |                                     |        |Engineering         |
   |                                     |        |Laboratories RTAC   |
   |                                     |        |product , followed  |
   |                                     |        |by a payload for one|
   |                                     |        |of a number of      |
   |                                     |        |industrial control  |
   |                                     |        |protocols.          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_BLUETOOTH_LE_LL            |  251   |Bluetooth Low Energy|
   |                                     |        |air interface Link  |
   |                                     |        |Layer packets, in   |
   |                                     |        |the format described|
   |                                     |        |in section 2.1      |
   |                                     |        |PACKET FORMAT of    |
   |                                     |        |volume 6 of the     |
   |                                     |        |Bluetooth           |
   |                                     |        |Specification       |
   |                                     |        |Version 4.0 (see PDF|
   |                                     |        |page 2200), but     |
   |                                     |        |without the         |
   |                                     |        |Preamble.           |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_WIRESHARK_UPPER_PDU        |  252   |Reserved for        |
   |                                     |        |Wireshark           |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_NETLINK                    |  253   |Linux Netlink       |
   |                                     |        |capture             |
   |                                     |        |encapsulation       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_BLUETOOTH_LINUX_MONITOR    |  254   |Bluetooth Linux     |



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   |                                     |        |Monitor             |
   |                                     |        |encapsulation of    |
   |                                     |        |traffic for the     |
   |                                     |        |BlueZ stack         |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_BLUETOOTH_BREDR_BB         |  255   |Bluetooth Basic Rate|
   |                                     |        |and Enhanced Data   |
   |                                     |        |Rate baseband       |
   |                                     |        |packets             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_BLUETOOTH_LE_LL_WITH_PHDR  |  256   |Bluetooth Low Energy|
   |                                     |        |link-layer packets  |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PROFIBUS_DL                |  257   |PROFIBUS data link  |
   |                                     |        |layer packets, as   |
   |                                     |        |specified by IEC    |
   |                                     |        |standard 61158-4-3, |
   |                                     |        |beginning with the  |
   |                                     |        |start delimiter,    |
   |                                     |        |ending with the end |
   |                                     |        |delimiter, and      |
   |                                     |        |including all octets|
   |                                     |        |between them.       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_PKTAP                      |  258   |Apple PKTAP capture |
   |                                     |        |encapsulation       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_EPON                       |  259   |Ethernet-over-      |
   |                                     |        |passive-optical-    |
   |                                     |        |network packets,    |
   |                                     |        |starting with the   |
   |                                     |        |last 6 octets of the|
   |                                     |        |modified preamble as|
   |                                     |        |specified by        |
   |                                     |        |65.1.3.2 Transmit in|
   |                                     |        |Clause 65 of        |
   |                                     |        |Section 5 of IEEE   |
   |                                     |        |802.3 , followed    |
   |                                     |        |immediately by an   |
   |                                     |        |Ethernet frame.     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IPMI_HPM_2                 |  260   |IPMI trace packets, |
   |                                     |        |as specified by     |
   |                                     |        |Table 3-20 Trace    |
   |                                     |        |Data Block Format in|
   |                                     |        |the PICMG HPM.2     |
   |                                     |        |specification The   |
   |                                     |        |time stamps for     |



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   |                                     |        |packets in this     |
   |                                     |        |format must match   |
   |                                     |        |the time stamps in  |
   |                                     |        |the Trace Data      |
   |                                     |        |Blocks.             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ZWAVE_R1_R2                |  261   |Z-Wave RF profile R1|
   |                                     |        |and R2 packets , as |
   |                                     |        |specified by ITU-T  |
   |                                     |        |Recommendation      |
   |                                     |        |G.9959 , with some  |
   |                                     |        |MAC layer fields    |
   |                                     |        |moved.              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ZWAVE_R3                   |  262   |Z-Wave RF profile R3|
   |                                     |        |packets , as        |
   |                                     |        |specified by ITU-T  |
   |                                     |        |Recommendation      |
   |                                     |        |G.9959 , with some  |
   |                                     |        |MAC layer fields    |
   |                                     |        |moved.              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_WATTSTOPPER_DLM            |  263   |Formats for         |
   |                                     |        |WattStopper Digital |
   |                                     |        |Lighting Management |
   |                                     |        |(DLM) and Legrand   |
   |                                     |        |Nitoo Open protocol |
   |                                     |        |common packet       |
   |                                     |        |structure captures. |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ISO_14443                  |  264   |Messages between ISO|
   |                                     |        |14443 contactless   |
   |                                     |        |smartcards          |
   |                                     |        |(Proximity          |
   |                                     |        |Integrated Circuit  |
   |                                     |        |Card, PICC) and card|
   |                                     |        |readers (Proximity  |
   |                                     |        |Coupling Device,    |
   |                                     |        |PCD), with the      |
   |                                     |        |message format      |
   |                                     |        |specified by the    |
   |                                     |        |PCAP format for     |
   |                                     |        |ISO14443            |
   |                                     |        |specification       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_RDS                        |  265   |Radio data system   |
   |                                     |        |(RDS) groups, as per|
   |                                     |        |IEC 62106,          |



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   |                                     |        |encapsulated in this|
   |                                     |        |form                |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_USB_DARWIN                 |  266   |USB packets,        |
   |                                     |        |beginning with a    |
   |                                     |        |Darwin (macOS, etc.)|
   |                                     |        |USB header          |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_OPENFLOW                   |  267   |Reserved for OpenBSD|
   |                                     |        |DLT_OPENFLOW        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SDLC                       |  268   |SDLC packets, as    |
   |                                     |        |specified by Chapter|
   |                                     |        |1, DLC Links,       |
   |                                     |        |section Synchronous |
   |                                     |        |Data Link Control   |
   |                                     |        |(SDLC) of Systems   |
   |                                     |        |Network Architecture|
   |                                     |        |Formats,            |
   |                                     |        |GA27-3136-20 ,      |
   |                                     |        |without the flag    |
   |                                     |        |fields, zero-bit    |
   |                                     |        |insertion, or Frame |
   |                                     |        |Check Sequence      |
   |                                     |        |field, containing   |
   |                                     |        |SNA path information|
   |                                     |        |units (PIUs) as the |
   |                                     |        |payload.            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_TI_LLN_SNIFFER             |  269   |Reserved for Texas  |
   |                                     |        |Instruments protocol|
   |                                     |        |sniffer             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LORATAP                    |  270   |LoRaTap pseudo-     |
   |                                     |        |header , followed by|
   |                                     |        |the payload, which  |
   |                                     |        |is typically the    |
   |                                     |        |PHYPayload from the |
   |                                     |        |LoRaWan             |
   |                                     |        |specification       |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_VSOCK                      |  271   |Protocol for        |
   |                                     |        |communication       |
   |                                     |        |between host and    |
   |                                     |        |guest machines in   |
   |                                     |        |VMware and KVM      |
   |                                     |        |hypervisors.        |
   +-------------------------------------+--------+--------------------+



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   | LINKTYPE_NORDIC_BLE                 |  272   |Messages to and from|
   |                                     |        |a Nordic            |
   |                                     |        |Semiconductor nRF   |
   |                                     |        |Sniffer for         |
   |                                     |        |Bluetooth LE        |
   |                                     |        |packets, beginning  |
   |                                     |        |with a pseudo-header|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DOCSIS31_XRA31             |  273   |DOCSIS packets and  |
   |                                     |        |bursts, preceded by |
   |                                     |        |a pseudo-header     |
   |                                     |        |giving metadata     |
   |                                     |        |about the packet    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ETHERNET_MPACKET           |  274   |mPackets, as        |
   |                                     |        |specified by IEEE   |
   |                                     |        |802.3br Figure 99-4,|
   |                                     |        |starting with the   |
   |                                     |        |preamble and always |
   |                                     |        |ending with a CRC   |
   |                                     |        |field.              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DISPLAYPORT_AUX            |  275   |DisplayPort AUX     |
   |                                     |        |channel monitoring  |
   |                                     |        |data as specified by|
   |                                     |        |VESA DisplayPort(DP)|
   |                                     |        |Standard preceded by|
   |                                     |        |a pseudo-header     |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_LINUX_SLL2                 |  276   |Linux cooked capture|
   |                                     |        |encapsulation v2    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_SERCOS_MONITOR             |  277   |Reserved for Sercos |
   |                                     |        |Monitor             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_OPENVIZSLA                 |  278   |Openvizsla FPGA-    |
   |                                     |        |based USB sniffer   |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_EBHSCR                     |  279   |Elektrobit High     |
   |                                     |        |Speed Capture and   |
   |                                     |        |Replay (EBHSCR)     |
   |                                     |        |format              |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_VPP_DISPATCH               |  280   |Records in traces   |
   |                                     |        |from the            |
   |                                     |        |http://fd.io VPP    |
   |                                     |        |graph dispatch      |
   |                                     |        |tracer, in the the  |



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   |                                     |        |graph dispatcher    |
   |                                     |        |trace format        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DSA_TAG_BRCM               |  281   |Ethernet frames,    |
   |                                     |        |with a switch tag   |
   |                                     |        |inserted between the|
   |                                     |        |source address field|
   |                                     |        |and the type/length |
   |                                     |        |field in the        |
   |                                     |        |Ethernet header.    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DSA_TAG_BRCM_PREPEND       |  282   |Ethernet frames,    |
   |                                     |        |with a switch tag   |
   |                                     |        |inserted before the |
   |                                     |        |destination address |
   |                                     |        |in the Ethernet     |
   |                                     |        |header.             |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_IEEE802_15_4_TAP           |  283   |IEEE 802.15.4 Low-  |
   |                                     |        |Rate Wireless       |
   |                                     |        |Networks, with a    |
   |                                     |        |pseudo-header       |
   |                                     |        |containing TLVs with|
   |                                     |        |metadata preceding  |
   |                                     |        |the 802.15.4 header.|
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DSA_TAG_DSA                |  284   |Ethernet frames,    |
   |                                     |        |with a switch tag   |
   |                                     |        |inserted between the|
   |                                     |        |source address field|
   |                                     |        |and the type/length |
   |                                     |        |field in the        |
   |                                     |        |Ethernet header.    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_DSA_TAG_EDSA               |  285   |Ethernet frames,    |
   |                                     |        |with a programmable |
   |                                     |        |Ethernet type switch|
   |                                     |        |tag inserted between|
   |                                     |        |the source address  |
   |                                     |        |field and the type/ |
   |                                     |        |length field in the |
   |                                     |        |Ethernet header.    |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ELEE                       |  286   |Payload of lawful   |
   |                                     |        |intercept packets   |
   |                                     |        |using the ELEE      |
   |                                     |        |protocol The packet |
   |                                     |        |begins with the ELEE|



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   |                                     |        |header; it does not |
   |                                     |        |include any         |
   |                                     |        |transport-layer or  |
   |                                     |        |lower-layer headers |
   |                                     |        |for protcols used to|
   |                                     |        |transport ELEE      |
   |                                     |        |packets.            |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_Z_WAVE_SERIAL              |  287   |Serial frames       |
   |                                     |        |transmitted between |
   |                                     |        |a host and a Z-Wave |
   |                                     |        |chip over an RS-232 |
   |                                     |        |or USB serial       |
   |                                     |        |connection, as      |
   |                                     |        |described in section|
   |                                     |        |5 of the Z-Wave     |
   |                                     |        |Serial API Host     |
   |                                     |        |Application         |
   |                                     |        |Programming Guide   |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_USB_2_0                    |  288   |USB 2.0, 1.1, or 1.0|
   |                                     |        |packet, beginning   |
   |                                     |        |with a PID, as      |
   |                                     |        |described by Chapter|
   |                                     |        |8 Protocol Layer of |
   |                                     |        |the the Universal   |
   |                                     |        |Serial Bus          |
   |                                     |        |Specification       |
   |                                     |        |Revision 2.0        |
   +-------------------------------------+--------+--------------------+
   | LINKTYPE_ATSC_ALP                   |  289   |ATSC Link-Layer     |
   |                                     |        |Protocol frames, as |
   |                                     |        |described in section|
   |                                     |        |5 of the A/330 Link-|
   |                                     |        |Layer Protocol      |
   |                                     |        |specification, found|
   |                                     |        |at the ATSC 3.0     |
   |                                     |        |standards page ,    |
   |                                     |        |beginning with a    |
   |                                     |        |Base Header         |
   +-------------------------------------+--------+--------------------+

                                  Table 1

9.  Contributors

   [Insert pcap developers etc. here].




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10.  Acknowledgments

   The authors wish to thank [insert list here] and many others for
   their invaluable comments.

11.  References

11.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

11.2.  Informative References

   [I-D.tuexen-opsawg-pcapng]
              Tuexen, M., Risso, F., Bongertz, J., Combs, G., Harris,
              G., and M. Richardson, "PCAP Next Generation (pcapng)
              Capture File Format", Work in Progress, Internet-Draft,
              draft-tuexen-opsawg-pcapng-02, 28 September 2020,
              <https://www.ietf.org/archive/id/draft-tuexen-opsawg-
              pcapng-02.txt>.

   [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/info/rfc8126>.

   [Radiotap] radiotap.org, "Radiotap Web site", n.d.,
              <http://www.radiotap.org/>.

   [AVS]      Peachy, S., "Archived AVS specification", n.d.,
              <http://web.archive.org/web/20040803232023/
              http://www.shaftnet.org/~pizza/software/capturefrm.txt>.

Authors' Addresses

   Guy Harris (editor)

   Email: gharris@sonic.net






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   Michael C. Richardson
   Sandelman Software Works Inc

   Email: mcr+ietf@sandelman.ca
   URI:   http://www.sandelman.ca/














































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