RFC7133: Information Elements for Data Link Layer Traffic Measurement

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Internet Engineering Task Force (IETF)                        S. Kashima
Request for Comments: 7133                                           NTT
Category: Standards Track                              A. Kobayashi, Ed.
ISSN: 2070-1721                                                 NTT East
                                                               P. Aitken
                                                     Cisco Systems, Inc.
                                                                May 2014


      Information Elements for Data Link Layer Traffic Measurement

Abstract

   This document describes Information Elements related to the data link
   layer.  They are used by the IP Flow Information Export (IPFIX)
   protocol for encoding measured data link layer traffic information.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc7133.

Copyright Notice

   Copyright (c) 2014 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
   (http://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.






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Table of Contents

   1. Introduction ....................................................4
      1.1. Conventions Used in This Document ..........................4
   2. Extended Ethernet Technology ....................................4
      2.1. Wide-Area Ethernet Technology Summary ......................4
      2.2. Virtual Ethernet Technology Summary ........................5
   3. Modification and Addition of Information Elements
      Related to Data Link Layer ......................................6
      3.1. Existing Information Elements ..............................7
           3.1.1. dataLinkFrameSize ...................................8
           3.1.2. dataLinkFrameSection ................................9
           3.1.3. layer2OctetDeltaCount ...............................9
           3.1.4. layer2OctetTotalCount ..............................10
           3.1.5. layer2FrameDeltaCount ..............................10
           3.1.6. layer2FrameTotalCount ..............................11
      3.2. New Information Elements ..................................11
           3.2.1. dataLinkFrameType ..................................12
           3.2.2. sectionOffset ......................................12
           3.2.3. sectionExportedOctets ..............................13
           3.2.4. dot1qServiceInstanceTag ............................13
           3.2.5. dot1qServiceInstanceId .............................14
           3.2.6. dot1qServiceInstancePriority .......................14
           3.2.7. dot1qCustomerSourceMacAddress ......................15
           3.2.8. dot1qCustomerDestinationMacAddress .................15
           3.2.9. postL2OctetDeltaCount ..............................16
           3.2.10. postMCastL2OctetDeltaCount ........................16
           3.2.11. postL2OctetTotalCount .............................17
           3.2.12. postMCastL2OctetTotalCount ........................17
           3.2.13. minimumL2TotalLength ..............................18
           3.2.14. maximumL2TotalLength ..............................18
           3.2.15. droppedL2OctetDeltaCount ..........................19
           3.2.16. droppedL2OctetTotalCount ..........................19
           3.2.17. ignoredL2OctetTotalCount ..........................20
           3.2.18. notSentL2OctetTotalCount ..........................20
           3.2.19. layer2OctetDeltaSumOfSquares ......................21
           3.2.20. layer2OctetTotalSumOfSquares ......................21
   4. Modification of Existing Information Elements Related
      to Packet Section ..............................................22
      4.1. ipHeaderPacketSection .....................................22
      4.2. ipPayloadPacketSection ....................................23
      4.3. mplsLabelStackSection .....................................24
      4.4. mplsPayloadPacketSection ..................................25
   5. Modification of Existing Information Elements Related
      to VLAN Tag ....................................................26
      5.1. dot1qVlanId ...............................................26
      5.2. dot1qPriority .............................................27
      5.3. dot1qCustomerVlanId .......................................27



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      5.4. dot1qCustomerPriority .....................................27
   6. The Relationship between Ethernet Header Fields and
      Information Elements ...........................................28
   7. Security Considerations ........................................29
   8. IANA Considerations ............................................29
   9. Acknowledgments ................................................30
   10. References ....................................................30
      10.1. Normative References .....................................30
      10.2. Informative References ...................................31
   Appendix A.  Frame Formats ........................................32
   Appendix B.  Template Format Example ..............................40








































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1.  Introduction

   Ethernet [IEEE802.1D] and VLAN (Virtual LAN) technologies had been
   used only in Local Area Networks.  Recently, they have been used in
   Wide Area Networks, e.g., Layer 2 VPN (L2 VPN) services.
   Accordingly, carrier networks using VLAN technologies have been
   enhanced to Provider Bridged Networks and Provider Backbone Bridged
   Networks [IEEE802.1Q].  In addition, Ethernet in data centers has
   also been enhanced for server virtualization and input/output (I/O)
   consolidation.

   While these innovations provide flexibility, scalability, and
   mobility to an existing network architecture, they increase the
   complexity of traffic measurement due to the existence of various
   Ethernet header formats.  To cope with this, a more sophisticated
   method of traffic measurement is required.

   IPFIX and Packet Sampling (PSAMP) help to resolve these problems.
   However, the PSAMP Information Model [RFC5477] and the IPFIX
   Information Model [RFC7011] don't yet contain enough Information
   Elements related to the data link layer, e.g., Ethernet header forms.
   This document describes existing and new Information Elements related
   to data link layers that enable a more sophisticated traffic
   measurement method.

   Note that this document does not update [RFC5477] or [RFC7011]
   because IANA's IPFIX registry [IANA-IPFIX] is the ultimate
   Information Element reference, per Section 1 of [RFC7012].

1.1.  Conventions Used in This Document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

2.  Extended Ethernet Technology

2.1.  Wide-Area Ethernet Technology Summary

   Provider Bridge and Provider Backbone Bridge [IEEE802.1Q], which are
   standards for Wide-Area Ethernet, are described below.

   o  In Provider Bridge [IEEE802.1Q], there are two VLAN IDs: Service
      VLAN Identifier (S-VID) and Customer VLAN Identifier (C-VID).
      S-VID is assigned to an Ethernet frame by a service provider,
      while C-VID is independently assigned to an Ethernet frame by a
      customer.  Frame switching in a service provider network is based
      on only S-VID.



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   o  In Provider Backbone Bridge [IEEE802.1Q], new Ethernet fields,
      such as Backbone VLAN Identifier (B-VID) and Backbone Service
      Instance Identifier (I-SID), are introduced to overcome the
      limitations on the VLAN identifier space and to isolate the
      service provider and customer identifier spaces.  Frame switching
      is based on a 12-bit B-VID, and customer identification is based
      on a 24-bit I-SID.  A flexible network design has become possible
      because network management is separated from customer management.
      Other Ethernet fields that indicate quality of service (QoS) class
      are Backbone VLAN Priority Code Point (B-PCP), Backbone VLAN Drop
      Eligible Indicator (B-DEI), Backbone Service Instance Priority
      Code Point (I-PCP), and Backbone Service Instance Drop Eligible
      Indicator (I-DEI).

   The Provider Backbone Bridge technologies have enhanced a Wide-Area
   Ethernet service from a flat network to a hierarchical network
   consisting of a Provider Bridged Network and Provider Backbone
   Bridged Network.

   Frame formats used in Wide-Area Ethernet are shown in Appendix A.

2.2.  Virtual Ethernet Technology Summary

   There have been several challenges in the existing virtual switches
   environment in a data center.  One is the lack of network management
   visibility: limited features on virtual switches make it difficult to
   monitor traffic among virtual machines (VMs).  Another is the lack of
   management scalability and flexibility: increasing the number of VMs
   for multi-tenant architecture causes an increase in the number of
   virtual switches and in the number of the traffic control policies,
   which reach the limitations of network management scalability and
   flexibility.

   In this situation, the IEEE 802.1 working group is standardizing
   virtual bridging technologies such as Edge Virtual Bridging (EVB),
   including two kinds of Edge Relays: Virtual Edge Bridge (VEB) and
   Virtual Edge Port Aggregator (VEPA) [IEEE802.1Qbg].  The VEB is a
   bridge that provides bridging among multiple VMs and the external
   bridging environment.  The VEPA is a bridge-like device on a host
   that forwards all internal traffic to the adjacent EVB bridge and
   then distributes any traffic received from the adjacent EVB bridge to
   VMs.  The VEPA makes all the VM-to-VM traffic visible to the EVB
   bridge so that the traffic can be monitored and so that the EVB
   bridge can apply filtering to the traffic.

   To improve flexibility, a virtual link between a host system and EVB
   bridge is standardized as S-channel.  S-channel allows a bridge to
   treat the traffic in the virtual link as if it comes in on a separate



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   port.  For example, in the host, an S-channel may be attached to a
   VEB or a VEPA or directly to an internal port in order to apply each
   port-based filtering rule to the traffic.  S-channel over the link
   between a host and its adjacent bridge uses Service VLAN Tag (S-TAG)
   [IEEE802.1Q].  When S-channel is in use, frames on the link carry an
   S-TAG to identify the S-channel.

   On the other hand, Bridge Port Extension emulates single Extended
   Bridge from multiple physical switches and virtual switches, and it
   also simplifies network management.  Also, it solves the lack of
   network management visibility by forwarding all traffic into a
   central Controlling Bridge using E-channel.  E-channel over the link
   between a Bridge Port Extender and a Controlling Bridge uses E-TAG
   defined in [IEEE802.1BR].

   Traffic monitoring over S-channel and E-channel is required in order
   to get visibility of VM-to-VM traffic and visibility of each
   channel's traffic on a virtual link.

   Frame formats with E-TAG used in E-channel and S-TAG used in
   S-channel are shown in Appendix A.  Though these frames carry special
   tags while on the link, those tags identify a virtual port (or for
   multicast in the downstream direction, a set of virtual ports) to
   which they are destined.  These tag values only have local meaning,
   and the Flow would be reported as sent and arriving on the
   corresponding virtual ports.  Therefore, IPFIX does not need to
   monitor data based on these tags.

3.  Modification and Addition of Information Elements Related to Data
    Link Layer

   The Information Elements listed in the upper section of Table 1 are
   necessary for enabling IPFIX and PSAMP traffic measurement for the
   data link layer, which is not limited to Ethernet because the method
   can be applied to other data link protocols as well.

   Information Elements in the middle section of Table 1 are necessary
   for enabling the IPFIX and PSAMP traffic measurement for
   [IEEE802.1Q].

   Information Elements in the lower section of Table 1 are octet
   counter or packet length for layer 2, and they are necessary for
   enabling IPFIX and PSAMP traffic measurement for the data link layer.








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               +-----+------------------------------------+
               | ID  | Name                               |
               +-----+------------------------------------+
               | 312 | dataLinkFrameSize                  |
               | 315 | dataLinkFrameSection               |
               | 408 | dataLinkFrameType                  |
               | 409 | sectionOffset                      |
               | 410 | sectionExportedOctets              |
               +-----+------------------------------------+
               | 411 | dot1qServiceInstanceTag            |
               | 412 | dot1qServiceInstanceId             |
               | 413 | dot1qServiceInstancePriority       |
               | 414 | dot1qCustomerSourceMacAddress      |
               | 415 | dot1qCustomerDestinationMacAddress |
               +-----+------------------------------------+
               | 352 | layer2OctetDeltaCount              |
               | 353 | layer2OctetTotalCount              |
               | 417 | postL2OctetDeltaCount              |
               | 418 | postMCastL2OctetDeltaCount         |
               | 420 | postL2OctetTotalCount              |
               | 421 | postMCastL2OctetTotalCount         |
               | 422 | minimumL2TotalLength               |
               | 423 | maximumL2TotalLength               |
               | 424 | droppedL2OctetDeltaCount           |
               | 425 | droppedL2OctetTotalCount           |
               | 426 | ignoredL2OctetTotalCount           |
               | 427 | notSentL2OctetTotalCount           |
               | 428 | layer2OctetDeltaSumOfSquares       |
               | 429 | layer2OctetTotalSumOfSquares       |
               | 430 | layer2FrameDeltaCount              |
               | 431 | layer2FrameTotalCount              |
               +-----+------------------------------------+

         Table 1: Information Elements Related to Data Link Layer

3.1.  Existing Information Elements

   Some existing Information Elements are required for data link layer
   export.  Their details are reproduced here from IANA's IPFIX registry
   [IANA-IPFIX].  Additions per this document appear between *.

   Section 3.1.1 introduces the missing Data Type Semantics for the
   dataLinkFrameSize Information Element, which is held to be an
   interoperable change per #4 in Section 5.2 of [RFC7013].







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   Section 3.1.2 extends the definition of the dataLinkFrameSection
   Information Element with reference to the new sectionOffset
   Information Element, which is also an interoperable change per #4 in
   Section 5.2 of [RFC7013].

   The layer2OctetDeltaCount Information Element reports the number of
   layer 2 octets since the previous report in incoming packets for this
   Flow, while the layer2OctetTotalCount Information Element reports the
   total number of layer 2 octets in incoming packets for this Flow.
   The layer2FrameDeltaCount Information Element reports the number of
   incoming layer 2 frames since the previous report for this Flow,
   while layer2FrameTotalCount Information Element reports the total
   number of incoming layer 2 frames for this Flow.  All of these
   Information Elements are unchanged from the existing IANA
   [IANA-IPFIX] definitions, and are reproduced in Section 3.1.3 through
   Section 3.1.6 below for completeness.

   Therefore, these changes do not introduce any backward-compatibility
   issues.

   Per Section 5.2 of [RFC7013], for each of these changes, [RFC7133]
   has been appended to the requester in IANA's IPFIX registry
   [IANA-IPFIX], the Information Element's revision number has been
   incremented by one, and the Information Element's revision date
   column has been updated.

3.1.1.  dataLinkFrameSize

   Description:

      This Information Element specifies the length of the selected data
      link frame.

      The data link layer is defined in [ISO/IEC.7498-1:1994].

   Abstract Data Type: unsigned16

   *Data Type Semantics: quantity*

   ElementId: 312

   References: [ISO/IEC.7498-1:1994]

   Status: current







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3.1.2.  dataLinkFrameSection

   Description:

      This Information Element carries n octets from the data link frame
      of a selected frame, starting sectionOffset octets into the frame.

      *However, if no sectionOffset field corresponding to this
      Information Element is present, then a sectionOffset of zero
      applies, and the octets MUST be from the start of the data link
      frame.*

      The sectionExportedOctets expresses how much data was observed,
      while the remainder is padding.

      When the sectionExportedOctets field corresponding to this
      Information Element exists, this Information Element MAY have a
      fixed length and MAY be padded, or it MAY have a variable length.

      When the sectionExportedOctets field corresponding to this
      Information Element does not exist, this Information Element
      SHOULD have a variable length and MUST NOT be padded.  In this
      case, the size of the exported section may be constrained due to
      limitations in the IPFIX protocol.

      Further Information Elements, i.e., dataLinkFrameType and
      dataLinkFrameSize, are needed to specify the data link type and
      the size of the data link frame of this Information Element.  A
      set of these Information Elements MAY be contained in a structured
      data type, as expressed in [RFC6313].  Or a set of these
      Information Elements MAY be contained in one Flow Record as shown
      in Appendix B of [RFC7133].

      The data link layer is defined in [ISO/IEC.7498-1:1994].

   Abstract Data Type: octetArray

   ElementId: 315

   References: [RFC6313] [RFC7133] [ISO/IEC.7498-1:1994]

   Status: current

3.1.3.  layer2OctetDeltaCount

   The layer2OctetDeltaCount Information Element is unchanged from the
   existing IANA [IANA-IPFIX] definition and is reproduced here for
   reference only.



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   Description

      The number of layer 2 octets since the previous report (if any) in
      incoming packets for this Flow at the Observation Point.  The
      number of octets includes layer 2 header(s) and layer 2 payload.

   Abstract Data Type: unsigned64

   Data Type Semantics: deltaCounter

   Units: octets

   ElementId: 352

   Status: current

3.1.4.  layer2OctetTotalCount

   The layer2OctetTotalCount Information Element is unchanged from the
   existing IANA [IANA-IPFIX] definition and is reproduced here for
   reference only.

   Description:

      The total number of layer 2 octets in incoming packets for this
      Flow at the Observation Point since the Metering Process
      (re-)initialization for this Observation Point.  The number of
      octets includes layer 2 header(s) and layer 2 payload.

   Abstract Data Type: unsigned64

   Data Type Semantics: totalCounter

   Units: octets

   ElementId: 353

   Status: current

3.1.5.  layer2FrameDeltaCount

   The layer2FrameDeltaCount Information Element is unchanged from the
   existing IANA [IANA-IPFIX] definition and is reproduced here for
   reference only.







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   Description:

      The number of incoming layer 2 frames since the previous report
      (if any) for this Flow at the Observation Point.

   Abstract Data Type: unsigned64

   Data Type Semantics: deltaCounter

   Units: frames

   ElementId: 430

   Status: current

3.1.6.  layer2FrameTotalCount

   The layer2FrameTotalCount Information Element is unchanged from the
   existing IANA [IANA-IPFIX] definition and is reproduced here for
   reference only.

   Description:

      The total number of incoming layer 2 frames for this Flow at the
      Observation Point since the Metering Process (re-)initialization
      for this Observation Point.

   Abstract Data Type: unsigned64

   Data Type Semantics: totalCounter

   Units: frames

   ElementId: 431

   Status: current

3.2.  New Information Elements

   The following new Information Elements have been added for data link
   layer monitoring.

   In IANA's IPFIX registry [IANA-IPFIX], the Requester has been set to
   [RFC7133], the Information Element's Revision has been set to zero,
   and the Information Element's Date set to the date upon which the new
   Information Elements have been added to the registry.  All other





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   columns that are not explicitly mentioned below (e.g., Units, Range,
   References) are not applicable and are to be left blank since the
   registry does not explicitly record "not applicable".

3.2.1.  dataLinkFrameType

   Description:

      This Information Element specifies the type of the selected data
      link frame.

      The following data link types are defined here:

      - 0x01 IEEE802.3 ETHERNET [IEEE802.3]

      - 0x02 IEEE802.11 MAC Frame format [IEEE802.11]

      Further values may be assigned by IANA.  Note that the assigned
      values are bits so that multiple observations can be OR'd
      together.

      The data link layer is defined in [ISO/IEC.7498-1:1994].

   Abstract Data Type: unsigned16

   Data Type Semantics: flags

   ElementId: 408

   References: [IEEE802.3] [IEEE802.11] [ISO/IEC.7498-1:1994]

   Status: current

3.2.2.  sectionOffset

   Description:

      This Information Element specifies the offset of the packet
      section (e.g., dataLinkFrameSection, ipHeaderPacketSection,
      ipPayloadPacketSection, mplsLabelStackSection, and
      mplsPayloadPacketSection).  If this Information Element is
      omitted, it defaults to zero (i.e., no offset).

      If multiple sectionOffset Information Elements are specified
      within a single Template, then they apply to the packet section
      Information Elements in order: the first sectionOffset applies to
      the first packet section, the second to the second, and so on.
      Note that the "closest" sectionOffset and packet section



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      Information Elements within a given Template are not necessarily
      related.  If there are fewer sectionOffset Information Elements
      than packet section Information Elements, then subsequent packet
      section Information Elements have no offset, i.e., a sectionOffset
      of zero applies to those packet section Information Elements.  If
      there are more sectionOffset Information Elements than the number
      of packet section Information Elements, then the additional
      sectionOffset Information Elements are meaningless.

   Abstract Data Type: unsigned16

   Data Type Semantics: quantity

   ElementId: 409

   Status: current

3.2.3.  sectionExportedOctets

   Description:

      This Information Element specifies the observed length of the
      packet section (e.g., dataLinkFrameSection, ipHeaderPacketSection,
      ipPayloadPacketSection, mplsLabelStackSection, and
      mplsPayloadPacketSection) when padding is used.

      The packet section may be of a fixed size larger than the
      sectionExportedOctets.  In this case, octets in the packet section
      beyond the sectionExportedOctets MUST follow the [RFC7011] rules
      for padding (i.e., be composed of zero (0) valued octets).

   Abstract Data Type: unsigned16

   Data Type Semantics: quantity

   ElementId: 410

   References: [RFC7011]

   Status: current

3.2.4.  dot1qServiceInstanceTag

   Description:

      This Information Element, which is 16 octets long, represents the
      Backbone Service Instance Tag (I-TAG) Tag Control Information
      (TCI) field of an Ethernet frame as described in [IEEE802.1Q].  It



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      encodes the Backbone Service Instance Priority Code Point (I-PCP),
      Backbone Service Instance Drop Eligible Indicator (I-DEI), Use
      Customer Addresses (UCAs), Backbone Service Instance Identifier
      (I-SID), Encapsulated Customer Destination Address (C-DA),
      Encapsulated Customer Source Address (C-SA), and reserved fields.
      The structure and semantics within the Tag Control Information
      field are defined in [IEEE802.1Q].

   Abstract Data Type: octetArray

   Data Type Semantics: default

   ElementId: 411

   References: [IEEE802.1Q]

   Status: current

3.2.5.  dot1qServiceInstanceId

   Description:

      The value of the 24-bit Backbone Service Instance Identifier
      (I-SID) portion of the Backbone Service Instance Tag (I-TAG) Tag
      Control Information (TCI) field of an Ethernet frame as described
      in [IEEE802.1Q].

   Abstract Data Type: unsigned32

   Data Type Semantics: identifier

   ElementId: 412

   References: [IEEE802.1Q]

   Status: current

   Range: The valid range is 0 - 16777215 (i.e., 24 bits).

3.2.6.  dot1qServiceInstancePriority

   Description:

      The value of the 3-bit Backbone Service Instance Priority Code
      Point (I-PCP) portion of the Backbone Service Instance Tag (I-TAG)
      Tag Control Information (TCI) field of an Ethernet frame as
      described in [IEEE802.1Q].




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   Abstract Data Type: unsigned8

   Data Type Semantics: identifier

   ElementId: 413

   References: [IEEE802.1Q]

   Status: current

   Range: The valid range is 0-7.

3.2.7.  dot1qCustomerSourceMacAddress

   Description:

      The value of the Encapsulated Customer Source Address (C-SA)
      portion of the Backbone Service Instance Tag (I-TAG) Tag Control
      Information (TCI) field of an Ethernet frame as described in
      [IEEE802.1Q].

   Abstract Data Type: macAddress

   Data Type Semantics: default

   ElementId: 414

   References: [IEEE802.1Q]

   Status: current

3.2.8.  dot1qCustomerDestinationMacAddress

   Description:

      The value of the Encapsulated Customer Destination Address (C-DA)
      portion of the Backbone Service Instance Tag (I-TAG) Tag Control
      Information (TCI) field of an Ethernet frame as described in
      [IEEE802.1Q].

   Abstract Data Type: macAddress

   Data Type Semantics: default

   ElementId: 415






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   References: [IEEE802.1Q]

   Status: current

3.2.9.  postL2OctetDeltaCount

   Description:

      The definition of this Information Element is identical to the
      definition of the layer2OctetDeltaCount Information Element,
      except that it reports a potentially modified value caused by a
      middlebox function after the packet passed the Observation Point.

      This Information Element is the layer 2 version of
      postOctetDeltaCount (ElementId #23).

   Abstract Data Type: unsigned64

   Data Type Semantics: deltaCounter

   ElementId: 417

   References: [RFC5477]

   Status: current

   Units: octets

3.2.10.  postMCastL2OctetDeltaCount

   Description:

      The number of layer 2 octets since the previous report (if any) in
      outgoing multicast packets sent for packets of this Flow by a
      multicast daemon within the Observation Domain.  This property
      cannot necessarily be observed at the Observation Point but may be
      retrieved by other means.  The number of octets includes layer 2
      header(s) and layer 2 payload.

      This Information Element is the layer 2 version of
      postMCastOctetDeltaCount (ElementId #20).

   Abstract Data Type: unsigned64

   Data Type Semantics: deltaCounter

   ElementId: 418




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   References: [RFC5477]

   Status: current

   Units: octets

3.2.11.  postL2OctetTotalCount

   Description:

      The definition of this Information Element is identical to the
      definition of the layer2OctetTotalCount Information Element,
      except that it reports a potentially modified value caused by a
      middlebox function after the packet passed the Observation Point.

      This Information Element is the layer 2 version of
      postOctetTotalCount (ElementId #171).

   Abstract Data Type: unsigned64

   Data Type Semantics: totalCounter

   ElementId: 420

   References: [RFC5477]

   Status: current

   Units: octets

3.2.12.  postMCastL2OctetTotalCount

   Description:

      The total number of layer 2 octets in outgoing multicast packets
      sent for packets of this Flow by a multicast daemon in the
      Observation Domain since the Metering Process (re-)initialization.
      This property cannot necessarily be observed at the Observation
      Point but may be retrieved by other means.  The number of octets
      includes layer 2 header(s) and layer 2 payload.

      This Information Element is the layer 2 version of
      postMCastOctetTotalCount (ElementId #175).

   Abstract Data Type: unsigned64

   Data Type Semantics: totalCounter




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   ElementId: 421

   References: [RFC5477]

   Status: current

   Units: octets

3.2.13.  minimumL2TotalLength

   Description:

      Layer 2 length of the smallest packet observed for this Flow.  The
      packet length includes the length of the layer 2 header(s) and the
      length of the layer 2 payload.

      This Information Element is the layer 2 version of
      minimumIpTotalLength (ElementId #25).

   Abstract Data Type: unsigned64

   ElementId: 422

   References: [RFC5477]

   Status: current

   Units: octets

3.2.14.  maximumL2TotalLength

   Description:

      Layer 2 length of the largest packet observed for this Flow.  The
      packet length includes the length of the layer 2 header(s) and the
      length of the layer 2 payload.

      This Information Element is the layer 2 version of
      maximumIpTotalLength (ElementId #26).

   Abstract Data Type: unsigned64

   ElementId: 423

   References: [RFC5477]






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   Status: current

   Units: octets

3.2.15.  droppedL2OctetDeltaCount

   Description:

      The number of layer 2 octets since the previous report (if any) in
      packets of this Flow dropped by packet treatment.  The number of
      octets includes layer 2 header(s) and layer 2 payload.

      This Information Element is the layer 2 version of
      droppedOctetDeltaCount (ElementId #132).

   Abstract Data Type: unsigned64

   Data Type Semantics: deltaCounter

   ElementId: 424

   References: [RFC5477]

   Status: current

   Units: octets

3.2.16.  droppedL2OctetTotalCount

   Description:

      The total number of octets in observed layer 2 packets (including
      the layer 2 header) that were dropped by packet treatment since
      the (re-)initialization of the Metering Process.

      This Information Element is the layer 2 version of
      droppedOctetTotalCount (ElementId #134).

   Abstract Data Type: unsigned64

   Data Type Semantics: totalCounter

   ElementId: 425

   References: [RFC5477]






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   Status: current

   Units: octets

3.2.17.  ignoredL2OctetTotalCount

   Description:

      The total number of octets in observed layer 2 packets (including
      the layer 2 header) that the Metering Process did not process
      since the (re-)initialization of the Metering Process.

      This Information Element is the layer 2 version of
      ignoredOctetTotalCount (ElementId #165).

   Abstract Data Type: unsigned64

   Data Type Semantics: totalCounter

   ElementId: 426

   References: [RFC5477]

   Status: current

   Units: octets

3.2.18.  notSentL2OctetTotalCount

   Description:

      The total number of octets in observed layer 2 packets (including
      the layer 2 header) that the Metering Process did not process
      since the (re-)initialization of the Metering Process.

      This Information Element is the layer 2 version of
      notSentOctetTotalCount (ElementId #168).

   Abstract Data Type: unsigned64

   Data Type Semantics: totalCounter

   ElementId: 427

   References: [RFC5477]






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   Status: current

   Units: octets

3.2.19.  layer2OctetDeltaSumOfSquares

   Description:

      The sum of the squared numbers of layer 2 octets per incoming
      packet since the previous report (if any) for this Flow at the
      Observation Point.  The number of octets includes layer 2
      header(s) and layer 2 payload.

      This Information Element is the layer 2 version of
      octetDeltaSumOfSquares (ElementId #198).

   Abstract Data Type: unsigned64

   Data Type Semantics: deltaCounter

   ElementId: 428

   References: [RFC5477]

   Status: current

   Units: octets

3.2.20.  layer2OctetTotalSumOfSquares

   Description:

      The total sum of the squared numbers of layer 2 octets in incoming
      packets for this Flow at the Observation Point since the Metering
      Process (re-)initialization for this Observation Point.  The
      number of octets includes layer 2 header(s) and layer 2 payload.

      This Information Element is the layer 2 version of
      octetTotalSumOfSquares (ElementId #199).

   Abstract Data Type: unsigned64

   Data Type Semantics: totalCounter

   ElementId: 429

   References: [RFC5477]




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   Status: current

   Units: octets

4.  Modification of Existing Information Elements Related to Packet
    Section

   The new Information Elements related to packet section (i.e.,
   sectionOffset and sectionExportedOctets) can be applied to not only
   dataLinkFrameSection but also to all kinds of packet section (i.e.,
   ipHeaderPacketSection, ipPayloadPacketSection, mplsLabelStackSection,
   and mplsPayloadPacketSection defined in [RFC5477]).  Therefore,
   existing Information Elements Descriptions should be modified as
   follows.

4.1.  ipHeaderPacketSection

   This Information Element is defined in [RFC5477].  The description
   has been updated from [RFC5477].

   Description:

      This Information Element carries a series of n octets from the IP
      header of a sampled packet, starting sectionOffset octets into the
      IP header.

      However, if no sectionOffset field corresponding to this
      Information Element is present, then a sectionOffset of zero
      applies, and the octets MUST be from the start of the IP header.

      With sufficient length, this element also reports octets from the
      IP payload.  However, full packet capture of arbitrary packet
      streams is explicitly out of scope per the Security Considerations
      sections of [RFC5477] and [RFC2804].

      The sectionExportedOctets expresses how much data was exported,
      while the remainder is padding.

      When the sectionExportedOctets field corresponding to this
      Information Element exists, this Information Element MAY have a
      fixed length and MAY be padded, or it MAY have a variable length.

      When the sectionExportedOctets field corresponding to this
      Information Element does not exist, this Information Element
      SHOULD have a variable length and MUST NOT be padded.  In this
      case, the size of the exported section may be constrained due to
      limitations in the IPFIX protocol.




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   Abstract Data Type: octetArray

   ElementId: 313

   References: [RFC2804] [RFC5477]

   Status: current

4.2.  ipPayloadPacketSection

   This Information Element is defined in [RFC5477].  The description is
   updated from [RFC5477].

   Description:

      This Information Element carries a series of n octets from the IP
      payload of a sampled packet, starting sectionOffset octets into
      the IP payload.

      However, if no sectionOffset field corresponding to this
      Information Element is present, then a sectionOffset of zero
      applies, and the octets MUST be from the start of the IP payload.

      The IPv4 payload is that part of the packet that follows the IPv4
      header and any options, which [RFC0791] refers to as "data" or
      "data octets".  For example, see the examples in [RFC0791],
      Appendix A.

      The IPv6 payload is the rest of the packet following the 40-octet
      IPv6 header.  Note that any extension headers present are
      considered part of the payload.  See [RFC2460] for the IPv6
      specification.

      The sectionExportedOctets expresses how much data was observed,
      while the remainder is padding.

      When the sectionExportedOctets field corresponding to this
      Information Element exists, this Information Element MAY have a
      fixed length and MAY be padded, or it MAY have a variable length.

      When the sectionExportedOctets field corresponding to this
      Information Element does not exist, this Information Element
      SHOULD have a variable length and MUST NOT be padded.  In this
      case, the size of the exported section may be constrained due to
      limitations in the IPFIX protocol.






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   Abstract Data Type: octetArray

   ElementId: 314

   References: [RFC0791] [RFC2460]

   Status: current

4.3.  mplsLabelStackSection

   This Information Element is defined in [RFC5477].  The description is
   updated from [RFC5477].

   Description:

      This Information Element carries a series of n octets from the
      MPLS label stack of a sampled packet, starting sectionOffset
      octets into the MPLS label stack.

      However, if no sectionOffset field corresponding to this
      Information Element is present, then a sectionOffset of zero
      applies, and the octets MUST be from the head of the MPLS label
      stack.

      With sufficient length, this element also reports octets from the
      MPLS payload.  However, full packet capture of arbitrary packet
      streams is explicitly out of scope per the Security Considerations
      sections of [RFC5477] and [RFC2804].

      See [RFC3031] for the specification of MPLS packets.

      See [RFC3032] for the specification of the MPLS label stack.

      The sectionExportedOctets expresses how much data was observed,
      while the remainder is padding.

      When the sectionExportedOctets field corresponding to this
      Information Element exists, this Information Element MAY have a
      fixed length and MAY be padded, or it MAY have a variable length.

      When the sectionExportedOctets field corresponding to this
      Information Element does not exist, this Information Element
      SHOULD have a variable length and MUST NOT be padded.  In this
      case, the size of the exported section may be constrained due to
      limitations in the IPFIX protocol.






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   Abstract Data Type: octetArray

   ElementId: 316

   References: [RFC2804] [RFC3031] [RFC3032] [RFC5477]

   Status: current

4.4.  mplsPayloadPacketSection

   This Information Element is defined in [RFC5477].  The description is
   updated from [RFC5477].

   Description:

      The mplsPayloadPacketSection carries a series of n octets from the
      MPLS payload of a sampled packet, starting sectionOffset octets
      into the MPLS payload, as it is data that follows immediately
      after the MPLS label stack.

      However, if no sectionOffset field corresponding to this
      Information Element is present, then a sectionOffset of zero
      applies, and the octets MUST be from the start of the MPLS
      payload.

      See [RFC3031] for the specification of MPLS packets.

      See [RFC3032] for the specification of the MPLS label stack.

      The sectionExportedOctets expresses how much data was observed,
      while the remainder is padding.

      When the sectionExportedOctets field corresponding to this
      Information Element exists, this Information Element MAY have a
      fixed length and MAY be padded, or it MAY have a variable length.

      When the sectionExportedOctets field corresponding to this
      Information Element does not exist, this Information Element
      SHOULD have a variable length and MUST NOT be padded.  In this
      case, the size of the exported section may be constrained due to
      limitations in the IPFIX protocol.

   Abstract Data Type: octetArray

   ElementId: 317






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   References: [RFC3031] [RFC3032]

   Status: current

5.  Modification of Existing Information Elements Related to VLAN Tag

   The traffic measurement using IPFIX and PSAMP for a Provider Backbone
   Bridged Network requires the Information Elements related to Backbone
   Service Instance Tag (I-TAG) and Backbone VLAN Tag (B-TAG).  The set
   of Information Elements related to I-TAG is added in Section 3,
   because I-TAG structure and semantics are different from that of
   Service VLAN Tag (S-TAG) and Customer VLAN Tag (C-TAG).  The set of
   Information Elements related to B-TAG reuses the existing Information
   Elements, because B-TAG structure and semantics are identical to that
   of C-TAG and S-TAG.  This section modifies existing descriptions and
   references related to C-TAG and S-TAG as follows.

5.1.  dot1qVlanId

   Description:

      The value of the 12-bit VLAN Identifier portion of the Tag Control
      Information field of an Ethernet frame.  The structure and
      semantics within the Tag Control Information field are defined in
      [IEEE802.1Q].  In Provider Bridged Networks, it represents the
      Service VLAN identifier in the Service VLAN Tag (S-TAG) Tag
      Control Information (TCI) field or the Customer VLAN identifier in
      the Customer VLAN Tag (C-TAG) Tag Control Information (TCI) field
      as described in [IEEE802.1Q].  In Provider Backbone Bridged
      Networks, it represents the Backbone VLAN identifier in the
      Backbone VLAN Tag (B-TAG) Tag Control Information (TCI) field as
      described in [IEEE802.1Q].  In a virtual link between a host
      system and EVB bridge, it represents the Service VLAN identifier
      indicating S-channel as described in [IEEE802.1Qbg].

      In the case of a multi-tagged frame, it represents the outer tag's
      VLAN identifier, except for I-TAG.

   Abstract Data Type: unsigned16

   Data Type Semantics: identifier

   ElementId: 243

   Status: current

   References: [IEEE802.1Q] [IEEE802.1Qbg]




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5.2.  dot1qPriority

   Description:

      The value of the 3-bit User Priority portion of the Tag Control
      Information field of an Ethernet frame.  The structure and
      semantics within the Tag Control Information field are defined in
      [IEEE802.1Q].  In the case of a multi-tagged frame, it represents
      the 3-bit Priority Code Point (PCP) portion of the outer tag's Tag
      Control Information (TCI) field as described in [IEEE802.1Q],
      except for I-TAG.

   Abstract Data Type: unsigned8

   Data Type Semantics: identifier

   ElementId: 244

   Status: current

   References: [IEEE802.1Q]

5.3.  dot1qCustomerVlanId

   Description:

      The value represents the Customer VLAN identifier in the Customer
      VLAN Tag (C-TAG) Tag Control Information (TCI) field as described
      in [IEEE802.1Q].

   Abstract Data Type: unsigned16

   Data Type Semantics: identifier

   ElementId: 245

   Status: current

   References: [IEEE802.1Q]

5.4.  dot1qCustomerPriority

   Description:

      The value represents the 3-bit Priority Code Point (PCP) portion
      of the Customer VLAN Tag (C-TAG) Tag Control Information (TCI)
      field as described in [IEEE802.1Q].




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   Abstract Data Type: unsigned8

   Data Type Semantics: identifier

   ElementId: 246

   Status: current

   References: [IEEE802.1Q]

6.  The Relationship between Ethernet Header Fields and Information
    Elements

   The following figures show a summary of various Ethernet header
   fields and the Informational Elements that would be used to represent
   each of the fields.

    <-- 6 --> <-- 6 --> <-- 4 --> <---- 2 ---->
   +---------+---------+---------+-------------+
   |         |         |         |             |
   |  C-DA   |  C-SA   |  C-TAG  | Length/Type |
   |    a    |    b    |    c    |      d      |
   +---------+---------+---------+-------------+

   a.(Information Element)  destinationMacAddress (80)
   b.(Information Element)  sourceMacAddress (56)
   c.(Information Elements) dot1qVlanId (243), dot1qPriority (244)
   d.(Information Element)  ethernetType (256)

               Figure 1: Customer-Tagged Frame Header Fields


    <-- 6 --> <-- 6 --> <-- 4 --> <-- 4 --> <---- 2 ---->
   +---------+---------+---------+---------+-------------+
   |         |         |         |         |             |
   |  C-DA   |  C-SA   |  S-TAG  |  C-TAG  | Length/Type |
   |    a    |    b    |    c    |    d    |      e      |
   +---------+---------+---------+---------+-------------+

   a.(Information Element)  destinationMacAddress (80)
   b.(Information Element)  sourceMacAddress (56)
   c.(Information Elements) dot1qVlanId (243), dot1qPriority (244)
   d.(Information Elements) dot1qCustomerVlanId (245),
                            dot1qCustomerPriority (246)
   e.(Information Element)  ethernetType (256)

               Figure 2: Service-Tagged Frame Header Fields




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    <-- 6 --> <-- 6 --> <-- 4 --> <--- 16 ---> <-- 4 --> <---- 2 ---->
   +---------+---------+---------+------------+---------+-------------+
   |         |         |         |            |         |             |
   |  B-DA   |  B-SA   |  B-TAG  |   I-TAG    |  C-TAG  | Length/Type |
   |    a    |    b    |    c    |     d      |    e    |      f      |
   +---------+---------+---------+------------+---------+-------------+

   a.(Information Element)  destinationMacAddress (80)
   b.(Information Element)  sourceMacAddress (56)
   c.(Information Elements) dot1qVlanId (243), dot1qPriority (244)
   d.(Information Elements) dot1qServiceInstanceTag (411), or
                            a set of dot1qServiceInstanceId (412),
                            dot1qServiceInstancePriority (413),
                            dot1qCustomerSourceMacAddress (414)
                            dot1qCustomerDestinationMacAddress (415),
   e.(Information Elements) dot1qCustomerVlanId (245),
                            dot1qCustomerPriority (246)
   f.(Information Element)  ethernetType (256)

            Figure 3: Backbone-VLAN-Tagged Frame Header Fields

7.  Security Considerations

   Reporting more granular data may increase the risk of DoS attacks
   against a Collector.  Protection against DoS attacks is discussed in
   Section 11.4 of [RFC7011].

   The recommendations in this document do not otherwise introduce any
   additional security issues beyond those already mentioned in
   [RFC7011] and [RFC5477].

8.  IANA Considerations

   Existing IPFIX Information Elements [IANA-IPFIX] have been modified
   as indicated in Sections 3.1, 4, and 5.

   Per Section 5.2 of [RFC7013], for each of these changes, [RFC7133]
   has been appended to the Requester in IANA's IPFIX registry
   [IANA-IPFIX], the Information Element's Revision number has been
   incremented by one, and the Information Element's revision Date
   column has been updated.

   New IPFIX Information Elements [IANA-IPFIX] have been allocated as
   shown in Section 3.2.







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9.  Acknowledgments

   Thanks to Brian Trammell and the IPFIX working group participants who
   contributed to mailing-list discussions throughout the development of
   this document.  Special thanks to Pat Thaler for her help with the
   IEEE 802 aspects of this work.

10.  References

10.1.  Normative References

   [IEEE802.11]   IEEE, "IEEE Standard for Information technology.
                  Telecommunications and information exchange between
                  systems Local and metropolitan area networks.
                  Specific requirements Part 11: Wireless LAN Medium
                  Access Control (MAC) and Physical Layer (PHY)
                  Specifications", IEEE Std 802.11-2012, March 2012.

   [IEEE802.1BR]  IEEE, "IEEE Standard for Local and metropolitan area
                  networks: Virtual Bridged Local Area Networks: Bridge
                  Port Extension", IEEE Std 802.1BR-2012, July 2012.

   [IEEE802.1Q]   IEEE, "IEEE Standard for Local and metropolitan area
                  networks: Media Access Control (MAC) Bridges and
                  Virtual Bridged Local Area Networks", IEEE Std
                  802.1Q-2011, August 2011.

   [IEEE802.1Qbg] IEEE, "IEEE Standard for Local and metropolitan area
                  networks: Media Access Control (MAC) Bridges and
                  Virtual Bridged Local Area Networks: Amendment 21:
                  Edge Virtual Bridging", IEEE Std 802.1Qbg-2012, July
                  2012.

   [IEEE802.3]    IEEE, "IEEE Standard for Ethernet", IEEE Std
                  802.3-2012, December 2012.

   [RFC0791]      Postel, J., "Internet Protocol", STD 5, RFC 791,
                  September 1981.

   [RFC2119]      Bradner, S., "Key words for use in RFCs to Indicate
                  Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2460]      Deering, S. and R. Hinden, "Internet Protocol, Version
                  6 (IPv6) Specification", RFC 2460, December 1998.

   [RFC3031]      Rosen, E., Viswanathan, A., and R. Callon,
                  "Multiprotocol Label Switching Architecture", RFC
                  3031, January 2001.



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   [RFC3032]      Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y.,
                  Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack
                  Encoding", RFC 3032, January 2001.

   [RFC5477]      Dietz, T., Claise, B., Aitken, P., Dressler, F., and
                  G.  Carle, "Information Model for Packet Sampling
                  Exports", RFC 5477, March 2009.

   [RFC6313]      Claise, B., Dhandapani, G., Aitken, P., and S. Yates,
                  "Export of Structured Data in IP Flow Information
                  Export (IPFIX)", RFC 6313, July 2011.

   [RFC7011]      Claise, B., Trammell, B., and P. Aitken,
                  "Specification of the IP Flow Information Export
                  (IPFIX) Protocol for the Exchange of Flow
                  Information", STD 77, RFC 7011, September 2013.

10.2.  Informative References

   [IANA-IPFIX]   IANA, "IP Flow Information Export (IPFIX) Entities",
                  <http://www.iana.org/assignments/ipfix>.

   [IEEE802.1D]   IEEE, "IEEE Standard for Local and metropolitan area
                  networks: Media Access Control (MAC) Bridges", IEEE
                  Std 802.1D-2004, June 2004.

   [ISO/IEC.7498-1:1994]
                  International Organization for Standardization,
                  "Information technology -- Open Systems
                  Interconnection -- Basic Reference Model: The Basic
                  Mode", ISO Standard 7498-1:1994, June 1996.

   [RFC2804]      IAB and IESG, "IETF Policy on Wiretapping", RFC 2804,
                  May 2000.

   [RFC7012]      Claise, B. and B. Trammell, "Information Model for IP
                  Flow Information Export (IPFIX)", RFC 7012, September
                  2013.

   [RFC7013]      Trammell, B. and B. Claise, "Guidelines for Authors
                  and Reviewers of IP Flow Information Export (IPFIX)
                  Information Elements", BCP 184, RFC 7013, September
                  2013.








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Appendix A.  Frame Formats

   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Length/Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                     Figure A-1: Untagged Frame Format


   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        C-TAG TPID=0x8100      |C-PCP|C|         C-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Length/Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Figure A-2: C-TAG Tagging Frame Format









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   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        S-TAG TPID=0x88a8      |S-PCP|D|         S-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Length/Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

    Figure A-3: S-TAG Tagging Frame Format in Provider Bridged Networks


   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        S-TAG TPID=0x88a8      |S-PCP|D|         S-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        C-TAG TPID=0x8100      |C-PCP|C|         C-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Length/Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure A-4: S-TAG and C-TAG Tagging Frame Format in Provider Bridged
                                 Networks






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   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              B-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              B-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        B-TAG TPID=0x88a8      |B-PCP|D|         B-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        I-TAG TPID=0x88e7      |I-PCP|D|U| Res |     I-SID     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             I-SID             |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-DA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-SA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |          Length/Type          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure A-5: B-TAG and I-TAG Tagging Frame Format in Provider Backbone
                             Bridged Networks






















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   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              B-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              B-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        B-TAG TPID=0x88a8      |B-PCP|D|         B-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        I-TAG TPID=0x88e7      |I-PCP|D|U| Res |     I-SID     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |             I-SID             |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-DA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-SA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |        C-TAG TCI=0x8100       |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |C-PCP|C|         C-VID         |          Length/Type          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Figure A-6: B-TAG, I-TAG, and C-TAG Tagging Frame Format in Provider
                         Backbone Bridged Networks




















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   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        S-TAG TPID=0x88a8      |S-PCP|D|         S-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Length/Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

    Figure A-7: S-TAG Tagging Frame Format for S-channel over the Link
              between an End Station and Its Adjacent Bridge

   Note: The frame format in Figure A-7 is identical to the format in
   Figure A-3.



























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   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        S-TAG TPID=0x88a8      |S-PCP|D|         S-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        C-TAG TPID=0x8100      |C-PCP|C|         C-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Length/Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Figure A-8: S-TAG and C-TAG Tagging Frame Format over the Link
              between an End Station and Its Adjacent Bridge

   Note: The frame format in Figure A-8 is identical to the format in
   Figure A-4.

























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   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        E-TAG TPID=0x893F      |E-PCP|D|   Ingress_E-CID_base  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Res|GRP|      E-CID_base       |Ingre_E-CID_ext|    E-CID_ext  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Length/Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Figure A-9: E-TAG Tagging Frame Format over the Link between a
               Controlling Bridge and a Bridge Port Extender




























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   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                              C-DA                             |
   +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                              C-SA                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        E-TAG TPID=0x893F      |E-PCP|D|   Ingress_E-CID_base  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Res|GRP|      E-CID_base       |Ingre_E-CID_ext|    E-CID_ext  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        C-TAG TPID=0x8100      |C-PCP|C|         C-VID         |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |          Length/Type          |                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
   |                                                               |
   ~                         Customer Data                         ~
   ~                                                               ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Figure A-10: E-TAG and C-TAG Tagging Frame Format over the Link
          between a Controlling Bridge and a Bridge Port Extender


























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RFC 7133          Data Link Layer Information Elements          May 2014


Appendix B.  Template Format Example

   0                   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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Set ID (2)             |             Length            |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |      Template ID (256)        |     Field Count (8)           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   ingressInterface (10)       |     Field Length (4)          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   egressInterface (14)        |     Field Length (4)          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | observationTimeSeconds (322)  |     Field Length (8)          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   dataLinkFrameSize (312)     |     Field Length (2)          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | dataLinkFrameSection (315)    |     Field Length (65535)      |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   dataLinkFrameType (408)     |     Field Length (2)          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     sectionOffset (409)       |     Field Length (2)          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | sectionExportedOctets (410)   |     Field Length (2)          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure B-1: Template Format Example
























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Authors' Addresses

   Shingo Kashima
   Nippon Telegraph and Telephone Corporation
   1-5-1 Otemachi
   Chiyoda-ku, Tokyo  100-8116
   Japan

   Phone: +81 3 6838 5267
   EMail: kashima@nttv6.net


   Atsushi Kobayashi
   Nippon Telegraph and Telephone East Corporation
   3-19-2 Nishi-shinjuku
   Shinjuku-ku, Tokyo  163-8019
   Japan

   Phone: +81 3 5359 4351
   EMail: akoba@nttv6.net


   Paul Aitken
   Cisco Systems, Inc.
   96 Commercial Quay
   Commercial Street, Edinburgh  EH6 6LX
   United Kingdom

   Phone: +44 131 561 3616
   EMail: paitken@cisco.com





















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