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Versions: (draft-claise-ipfix-mediation-protocol) 00 01 02 03 04 05 06 07 08 09 10 RFC 7119

     IPFIX Working Group                                    B. Claise
     Internet-Draft                               Cisco Systems, Inc.
     Intended Status: Standards Track                    A. Kobayashi
     Expires: June 5, 2012                                NTT PF Lab.
                                                          B. Trammell
                                                           ETH Zurich
                                                     December 5, 2011
     
     
            Specification of the Protocol for IPFIX Mediation
                  draft-ietf-ipfix-mediation-protocol-00
     
     
     Abstract
     
        This document specifies the IP Flow Information Export
        (IPFIX) protocol specific to Mediation.
     
     Status of this Memo
     
        This Internet-Draft is submitted to IETF in full conformance
        with the provisions of BCP 78 and BCP 79.
     
        Internet-Drafts are working documents of the Internet
        Engineering Task Force (IETF), its areas, and its working
        groups.  Note that other groups may also distribute working
        documents as Internet-Drafts.
     
        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."
     
        The list of current Internet-Drafts can be accessed at
        http://www.ietf.org/ietf/1id-abstracts.txt
     
        The list of Internet-Draft Shadow Directories can be accessed at
        http://www.ietf.org/shadow.html
     
        This Internet-Draft will expire on April, 2011.
     
     
     Copyright Notice
     
        Copyright (c) 2011 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
     
     

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        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.
     
     
     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].
     
     
     Table of Contents
     
     
        1. Introduction............................................. 4
           1.1. IPFIX Documents Overview............................ 5
           1.2. IPFIX Mediator Documents Overview................... 5
           1.3. Relationship with IPFIX and PSAMP................... 7
        2. Terminology.............................................. 7
        3. Specifications.......................................... 10
           3.1. Encoding of IPFIX Message Header................... 11
           3.2. Template Management................................ 13
              3.2.1. Template Management Without Template Records
              Change............................................... 13
              3.2.2. Template Management With New Template Records. 16
           3.3. Time Management.................................... 20
           3.4. Observation Point Management....................... 21
              3.4.1. Observation Domain Management................. 23
           3.5. Specific Reporting Requirements.................... 24
              3.5.1. The Flow Keys Options Template................ 24
              3.5.2. IPFIX Protocol Options Template............... 25
              3.5.3. IPFIX Mediator Options Template............... 25
           3.6. The Collecting Process's Side...................... 26
           3.7. Configuration Management........................... 26
        4. New Information Elements................................ 26
        5. Security Considerations................................. 27
        6. IANA Considerations..................................... 27
           6.1. originalExporterIPv4Address........................ 28
           6.2. originalExporterIPv6Address........................ 28
           6.3. originalObservationDomainId........................ 28
        7. References.............................................. 29
           7.1. Normative References............................... 29
           7.2. Informative References............................. 30
     
     
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        8. Author's Addresses...................................... 31
        Appendix A.  Additions to XML Specification of IPFIX
        Information Elements....................................... 32
     
     
        TO DO:
        - Change the reference from RFC5102 to RFC5102bis, or should we
          list IANA?
        - There are still changes in RFC5101bis that must be integrated
          here. Example: Template withdrawal and template life time
        - Definition change proposal for the Intermediate Process,
          Intermediate Conversion Process, Intermediate Selection
          Process, Intermediate Anonymization Process, and IPFIX
          Mediator.  See http://www.ietf.org/mail-
          archive/web/ipfix/current/msg05969.html. However, the
          definitions are copied over verbatim from RFC6183. Also note
          that Intermediate Anonymization Process in this document is
          not in line with the RFC6235.
        - "the IPFIX Mediator MAY keep the export time received from
          the incoming Transport Session", and " Therefore, as there is
          not a single rule that fits all different situations, the
          precise rules of applying the Flow Record timestamps in IPFIX
          Mediators is out of the scope of this document." Do we need
          something more specific?
        - Agree upon "Practically, the Original Exporters will not
          exporting these Information Elements. Therefore, the
          Intermediate Process SHOULD report the Original Observation
          Point(s) to the best of its knowledge.  Note that the
          Configuration Data Model for IPFIX and PSAMP [IPFIX-CONF] may
          help."
        - What Paul Aikten would like to see in section 3.5:
             What about IE ordering? May an exporter re-order received
             fields? eg, two devices sending the same information,
             though with the fields in a different order. Or the
             mediator is extracting the same information from two
             sources. That seems to be a valid scenario. eg, this
             reduces the number of templates received at the collector.
     
             What about temporal re-ordering? How should a mediator deal
             with out-of-order data coming from multiple devices? It
             can't expect all received data to be in time order.
     
             What should a mediator do with a field which it doesn't
             know/understand? Inevitably, exporters will be updated
             without mediators keeping in step. It's also very likely
             that mediators will see Enterprise-specific IEs. May a
             mediator re-export unknown IEs unchanged, or should it drop
     
     
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             them? Presumably a mediator may report received Enterprise-
             specific IEs even from multiple different Enterprises.
     
             What if an unknown field depends on the field ordering? eg,
             it's a bitfield like flowKeyIndicator. Re-ordering, adding
             or removing fields breaks the meaning of this field, so it
             can't be passed on. It can only be used if the received
             fields are reported unchanged.
     
     
     
     1. Introduction
     
        The IPFIX architectural components in [RFC5470] consist of
        IPFIX Devices and IPFIX Collectors communicating using the
        IPFIX protocol [RFC5101bis], which specifies how to export IP
        Flow information.  This protocol is designed to export
        information about IP traffic Flows and related measurement
        data, where a Flow is defined by a set of key attributes
        (e.g. source and destination IP address, source and
        destination port, etc.).
     
        However, thanks to its Template mechanism, the IPFIX protocol
        can export any type of information, as long as the relevant
        Information Element is specified in the IPFIX Information
        Model [RFC5102], registered with IANA, or specified as an
        enterprise-specific Information Element.  The specifications
        in the IPFIX protocol [RFC5101bis] have not been defined in
        the context of an IPFIX Mediator receiving, aggregating,
        correlating, anonymizing, etc... Flow Records from the one or
        multiple Exporters.  Indeed, the IPFIX protocol must be
        adapted for Intermediate Processes, as defined in the IPFIX
        Mediation Reference Model as specified in Figure A of [IPFIX-
        MED-FMWK], which is based on the IPFIX Mediation Problem
        Statement [RFC5982].
     
        This document specifies the IP Flow Information Export
        (IPFIX) protocol in the context of the implementation and
        deployment of IPFIX Mediators.  The use of the IPFIX
        protocol within a Mediator -- a device which contains both
        as a Collecting Process and an Exporting Process -- has an
        impact on the technical details of the usage of the
        protocol.  An overview of the technical problem is covered
        in section 6 of [RFC5982]: loss of original exporter
        information, loss of base time information, transport
        sessions management, loss of Options Template Information,
        Template Id management, considerations for network
     
     
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        topology, IPFIX Mediation interpretation, and
        considerations for aggregation.
     
        The specifications in this document are based on the IPFIX
        protocol specifications [RFC5101bis] but adapted according
        to the IPFIX Mediation Framework [IPFIX-MED-FMWK].
     
     
     1.1. IPFIX Documents Overview
     
        The IPFIX Protocol [RFC5101bis] provides network
        administrators with access to IP Flow information.
     
        The architecture for the export of measured IP Flow
        information out of an IPFIX Exporting Process to a Collecting
        Process is defined in the IPFIX Architecture [RFC5470], per
        the requirements defined in the IPFIX Requirement doc,
        [RFC3917].
     
        The IPFIX Architecture [RFC5470] specifies how IPFIX Data
        Records and Templates are carried via a congestion-aware
        transport protocol from IPFIX Exporting Processes to IPFIX
        Collecting Processes.
     
        IPFIX has a formal description of IPFIX Information Elements,
        their name, type and additional semantic information, as
        specified in the IPFIX Information Model [RFC5102].
     
        The IPFIX Applicability Statement [RFC5472] describes what
        type of applications can use the IPFIX protocol and how they
        can use the information provided.  It furthermore shows how
        the IPFIX framework relates to other architectures and
        frameworks.
     
        "IPFIX Mediation: Problem Statement" [RFC5982], describing the
        IPFIX Mediation applicability examples, along with some problems
        that network administrators have been facing, is the basis for
        the "IPFIX Mediation: Framework" [IPFIX-MED-FMWK].  This
        framework details the IPFIX Mediation reference model and the
        components of an IPFIX Mediator.
     
     
     1.2. IPFIX Mediator Documents Overview
     
        The "IPFIX Mediation: Problem Statement" [RFC5982] provides an
        overview of the applicability of Mediators, and defines
        requirements for Mediators in general terms.  This document is
     
     
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        of use largely to define the problems to be solved through the
        deployment of IPFIX Mediators, and to provide scope to the role
        of Mediators within an IPFIX collection infrastructure.
     
        The "IPFIX Mediation: Framework" [IPFIX-MED-FMWK] provides more
        architectural details of the arrangement of Intermediate
        Processes within a Mediator.
     
        The details of specific Intermediate Processes, when these have
        additional export specifications (e.g., metadata about the
        intermediate processing conveyed through IPFIX Options
        Templates), are each treated in their own document (e.g., the
        "IP Flow Anonymization Support" [RFC6235]).  Documents
        specifying the operations of specific Intermediate Processes
        cover the operation of these Processes within the Mediator
        framework, and comply with the specifications given in this
        document; they may additionally specify the operation of the
        process independently, outside the context of a Mediator, when
        this is appropriate.  As of today, these documents are:
     
        1. "IP Flow Anonymization Support", [RFC6235], which describes
        Anonymization techniques for IP flow data and the export of
        Anonymized data using the IPFIX protocol.
     
        2. "Flow Selection Techniques" [IPFIX-MED-FLOWSEL], which
        describes the process of selecting a subset of flows from all
        flows observed at an observation point, the flow selection
        motivations, and some specific flow selection techniques.
     
        3. "Exporting Aggregated Flow Data using the IP Flow Information
        Export" [IPFIX-MED-AGGR] which describes Aggregated Flow export
        within the framework of IPFIX Mediators and defines an
        interoperable, implementation-independent method for Aggregated
        Flow export.
     
        This document specifies the IP Flow Information Export
        (IPFIX) protocol specific to Mediation, i.e. the
        specifications that all Intermediate Processes type must
        comply to.  Some extra specifications might be required per
        Intermediate Process type (In which case, the Intermediate
        Process specific document would cover those).
     
     
     
     
     
     
     
     
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     1.3. Relationship with IPFIX and PSAMP
     
        The specification in this document applies to the IPFIX
        protocol specifications [RFC5101bis].  All specifications
        from [RFC5101bis] apply unless specified otherwise in this
        document.
     
        As the Packet Sampling (PSAMP) protocol specifications
        [RFC5476] are based on the IPFIX protocol specifications, the
        specifications in this document are also valid for the PSAMP
        protocol.  Therefore, the method specified by this document
        also applies to PSAMP.
     
     
     2. Terminology
     
        The IPFIX-specific terms, such as Observation Domain, Flow, Flow
        Key, Metering Process, Exporting Process, Exporter, IPFIX
        Device, Collecting Process, Collector, Template, IPFIX Message,
        Message Header, Template Record, Data Record, Options Template
        Record, Set, Data Set, Information Element, and Transport
        Session, used in this document are defined in [RFC5101bis].
        The PSAMP-specific terms used in this document, such as
        Filtering and Sampling are defined in [RFC5476].
     
        The IPFIX Mediation terms related to the aggregation, such as
        the Interval, Aggregated Flow, and Aggregated Function are
        defined in [IPFIX-MED-AGGR].
     
        The IPFIX Mediation-specific terminology used in this document
        is defined in "IPFIX Mediation: Problem Statement" [RFC5982],
        and reused in "IPFIX Mediation: Framework" [IPFIX-MED-FMWK].
        However, since both of those documents are an informational
        RFCs, the definitions have been reproduced here along with
        additional definitions.
     
        Similarly, since [RFC6235] is an experimental RFC, the
        Anonymization Record, Anonymized Data Record, and Intermediate
        Anonymization Process terms, specified in [RFC6235], are also
        reproduced here.
     
        In this document, as in [RFC5101bis], [RFC5476], [IPFIX-MED-
        AGGR], and [RFC6235], the first letter of each IPFIX-specific
        and PSAMP-specific term is capitalized along with the IPFIX
        Mediation-specific term defined here.  In this document, we call
        a stream of records carrying flow- or packet-based information a
     
     
     
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        "record stream".  The records may be encoded as IPFIX Data
        Records of any other format.
     
        Transport Session Information
     
         The Transport Session is specified in [RFC5101bis].  In SCTP,
         the Transport Session Information is the SCTP association.  In
         TCP and UDP, the Transport Session Information corresponds to
         a 5-tuple {Exporter IP address, Collector IP address, Exporter
         transport port, Collector transport port, transport protocol}.
     
        Original Exporter
     
          An Original Exporter is an IPFIX Device that hosts the
          Observation Points where the metered IP packets are observed.
     
        Original Observation Point
     
         An Observation Point of the Original Exporter.  In the case of
         the Intermediate Aggregation Process on an IPFIX Mediator, the
         Original Observation Point can be composed of, but not limited
         to, a (set of) specific exporter(s), a (set of) specific
         interface(s) on an Exporter, a (set of) line card(s) on an
         Exporter, or any combinations of these.
     
        IPFIX Mediation
     
          IPFIX Mediation is the manipulation and conversion of a record
          stream for subsequent export using the IPFIX protocol.
     
        The following terms are used in this document to describe the
        architectural entities used by IPFIX Mediation.
     
        Intermediate Process
     
          An Intermediate Process takes a record stream as its input
          from Collecting Processes, Metering Processes, IPFIX File
          Readers, other Intermediate Processes, or other record
          sources; performs some transformations on this stream, based
          upon the content of each record, states maintained across
          multiple records, or other data sources; and passes the
          transformed record stream as its output to Exporting
          Processes, IPFIX File Writers, or other Intermediate
          Processes, in order to perform IPFIX Mediation. Typically, an
          Intermediate Process is hosted by an IPFIX Mediator.
          Alternatively, an Intermediate Process may be hosted by an
          Original Exporter.
     
     
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        IPFIX Mediator
     
          An IPFIX Mediator is an IPFIX Device that provides IPFIX
          Mediation by receiving a record stream from some data sources,
          hosting one or more Intermediate Processes to transform that
          stream, and exporting the transformed record stream into IPFIX
          Messages via an Exporting Process.  In the common case, an
          IPFIX Mediator receives a record stream from a Collecting
          Process, but it could also receive a record stream from data
          sources not encoded using IPFIX, e.g., in the case of
          conversion from the NetFlow V9 protocol [RFC3954] to IPFIX
          protocol.
     
        Specific Intermediate Processes are described below.  However,
        this is not an exhaustive list.
     
          Intermediate Conversion Process
     
            An Intermediate Conversion Process is an Intermediate
            Process that transforms non-IPFIX into IPFIX, or manages the
            relation among Templates and states of incoming/outgoing
            Transport Sessions (or equivalent for non IPFIX protocols)
            in the case of transport protocol conversion (e.g., from UDP
            to SCTP).
     
          Intermediate Aggregation Process
     
            An Intermediate Aggregation Process is an Intermediate
            Process that aggregates records based upon a set of Flow
            Keys or functions applied to fields from the record (e.g.,
            binning and subnet aggregation).
     
          Intermediate Correlation Process
     
            An Intermediate Correlation Process is an Intermediate
            Process that adds information to records, noting
            correlations among them, or generates new records with
            correlated data from multiple records (e.g., the production
            of bidirectional flow records from unidirectional flow
            records).
     
          Intermediate Selection Process
     
            An Intermediate Selection Process is an Intermediate Process
            that selects records from a sequence based upon criteria-
            evaluated record values and passes only those records that
     
     
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            match the criteria (e.g., Filtering only records from a
            given network to a given Collector).
     
          Intermediate Anonymization Process
     
            An Intermediate Anonymization Process is an Intermediate
            Process that transforms records in order to anonymize them,
            to protect the identity of the entities described by the
            records (e.g., by applying prefix-preserving
            pseudonymization of IP addresses).
     
          Template Mapping
     
           A mapping from Template Records and/or Options Template
           Records received by a Mediator to Template Records and/or
           Options Template Records sent by that IPFIX Mediator.  Each
           entry in a Template Mapping is scoped by incoming or
           outgoing Transport Session and Observation Domain, as with
           Templates and Options Templates in the IPFIX Protocol.
     
          Anonymization Record
     
           A record, defined by the Anonymization Options Template in
           Section 6.1, that defines the properties of the
           Anonymization applied to a single Information Element within
           a single Template or Options Template.
     
          Anonymized Data Record
     
           A Data Record within a Data Set containing at least one
           Information Element with Anonymized values.  The Information
           Element(s) within the Template or Options Template
           describing this Data Record SHOULD have a corresponding
           Anonymization Record.
     
     
     3. Specifications
     
        This section describes the IPFIX specifications for Mediation:
        more specifically,  specifications for generic Intermediate
        Processes.  Possible specific Intermediate Processes are:
        Intermediate Conversion Process, Intermediate Aggregation
        Process, Intermediate Correlation Process, Intermediate
        Selection Process, Intermediate Anonymization Process.
     
     
     
     
     
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        For a specific Intermediate Process, the specifications in the
        following references MUST be followed, on top of the
        specifications in this document:
     
          - For the Intermediate Aggregation Process, the
            specifications in [IPFIX-MED-AGGR] MUST be followed.
     
          - For the Intermediate Selection Process, the specifications
            in [IPFIX-MED-FLOWSEL] MUST be followed.
     
          - For the Intermediate Anonymization Process, the
            specifications in [RFC6235] should be considered as
            guidelines as [RFC6235] is an experimental RFC.
     
       Note that no specific document deals with the Intermediate
       Conversion Process at the time of this publication.
     
       These new specifications, which are more specific compared than
       [RFC5101bis], are described with the key words described in
       [RFC2119].
     
     3.1. Encoding of IPFIX Message Header
     
        The format of the IPFIX Message Header is shown in Figure A.
        Note that the format is similar to the IPFIX Message in
        [RFC5101bis], but some field definitions (for the example, the
        Export Time) have been updated in the context of the IPFIX
        Mediator.
     
     
       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |       Version Number          |            Length             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                           Export Time                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       Sequence Number                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                    Observation Domain ID                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     
     
                      Figure A: IPFIX Message Header format
     
     
     
     
     
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        Message Header Field Descriptions
     
        Version
     
                Version of Flow Record format exported in this message.
                The value of this field is 0x000a for the current
                version, incrementing by one the version used in the
                NetFlow services export version 9 [RFC3954].
     
        Length
     
                Total length of the IPFIX Message, measured in octets,
                including Message Header and Set(s).
     
        Export Time
     
                Time at which the IPFIX Message Header leaves the
                Mediator, expressed in seconds since the UNIX epoch of
                1 January 1970 at 00:00 UTC, encoded as an unsigned 32-
                bit integer.
     
        Sequence Number
     
                Incremental sequence counter modulo 2^32 of all IPFIX
                Data Records sent on this PR-SCTP stream from the
                current Observation Domain by the Exporting Process.
                Check the specific meaning of this field in the sub-
                sections of section 10 when UDP or TCP is selected as
                the transport protocol.  This value SHOULD be used by
                the Collecting Process to identify whether any IPFIX
                Data Records have been missed.  Template and Options
                Template Records do not increase the Sequence Number.
                RFC'S EDITOR: section 10 referred to RFC5101. Now it
                must be aligned with RFC5101bis
     
        Observation Domain ID
     
                A 32-bit identifier of the Observation Domain that is
                locally unique to the Exporting Process.  The Exporting
                Process uses the Observation Domain ID to uniquely
                identify to the Collecting Process the Observation
                Domain that metered the Flows.  It is RECOMMENDED that
                this identifier is also unique per IPFIX
                Device.  Collecting Processes SHOULD use the Transport
                Session and the Observation Domain ID field to separate
                different export streams originating from the same
     
     
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                Exporting Process.  The Observation Domain ID SHOULD be
                0 when no specific Observation Domain ID is relevant for
                the entire IPFIX Message.  For example, when exporting
                the Exporting Process Statistics, or in case of
                hierarchy of Collector when aggregated Data Records are
                exported.
                Note: the Observation Domain Management is discussed in
                section 3.4.1.
     
     
     3.2. Template Management
     
     3.2.1. Template Management Without Template Records Change
     
        The first case is a situation where the IPFIX Mediator doesn't
        modify the (Options) Template Record(s) content.  A typical
        example is an Intermediate Selection Process acting as
        distributor, which collects Flow Records from one or more
        Exporters, and based on the Information Elements content,
        redirects the Flow Records to the appropriate Collector.  This
        example is a typical case of a single network operation center
        managing multiple universities: an unique IPFIX Collector
        collects all Flow Records for the common infrastructure, but
        might be re-exporting specific university Flow Records to the
        responsible system administrator.
     
        As specified in [RFC5101bis], the Template IDs are unique per
        Exporter, per Transport Session, and per Observation Domain.  As
        there is no guarantee that, for similar Template Records, the
        Template IDs received on the incoming Transport Session and
        exported to the outgoing Transport Session would be same, the
        IPFIX Mediator MUST maintain a Template Mapping composed of
        related received and exported (Options) Template Records:
     
          - for each received (Options) Template Record: Template
            Record Flow Keys and non Flow Keys, Template ID,
            Observation Domain Id, and Transport Session Information
     
          - for each exported (Options) Template Record: Template
            Record Flow Keys and non Flow Keys, Template ID, Collector,
            Observation Domain Id, and Transport Session Information
     
        If an IPFIX Mediator receives an IPFIX Withdrawal Message for a
        (Options) Template Record that is not used anymore in any other
        Template Mappings, the IPFIX Mediator SHOULD export the
        appropriate IPFIX Withdrawal Message(s) on the outgoing
     
     
     
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        Transport Session, and remove the corresponding entry in the
        Template Mapping.
     
        If a (Options) Template Record is not used anymore in an
        outgoing Transport Session, it MUST be withdrawn with an IPFIX
        Template Withdrawal Message on that specific outgoing Transport
        Session, and its entry MUST be removed from the Template
        Mapping.
     
        If an incoming or outgoing Transport Session is gracefully
        shutdown or reset, the (Options) Template Records corresponding
        to that Transport Session MUST be removed from the Template
        Mapping.
     
        For example, Figure B displays an example of an Intermediate
        Selection Process, re-distributing Data Records to Collectors on
        the basis of customer networks, i.e. the Route Distinguisher
        (RD).  In this example, the Template Record received from the
        Exporter#1 is reused towards Collector#1, Collector#2, and
        Collector#3.
     
     
                                         Templ. .---------.
                                         ID 256 |         |
                                          .---->|Collector|<==>Customer
                                          |     |#1       |    #A
                                          |     |         |
                                       RD=100:1 '---------'
        .---------.Templ.  .---------.    |
        |         |Id      |         |----'     .---------.
        |         |258     |         | RD=100:2 |         |
        |IPFIX    |------->|IPFIX    |--------->|Collector|<==>Customer
        |Exporter |        |Mediator | Templ.   |#2       |    #B
        |#1       |        |         | ID 257   |         |
        |         |        |         |----.     '---------'
        '---------'        '---------'    |
                                         RD=100:3
                                    Templ.|     .---------.
                                    ID    |     |         |
                                    257   '---->|Collector|<==>Customer
                                                |#3       |    #C
                                                |         |
                                                '---------'
     
             Figure B: Intermediate Aggregation Process Example
     
        The following table shows the Template Mapping for the system
        shown in Figure B.
     
     
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        Template Entry A:
         Incoming Transport Session Information (from Exporter#1):
           Source IP: <Exporter#1 export IP address>
           Destination IP: <IPFIX Mediator IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
         Template Id: 258
           Flow Keys: <series of Flow Keys>
           Non Flow Keys: <series of non Flow Keys>
     
        Template Entry B:
         Outgoing Transport Session Information (to Collector#1):
           Source IP: <IPFIX Mediator IP address>
           Destination IP: <IPFIX Collector#1 IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
         Template Id: 256
           Flow Keys: <series of Flow Keys>
           Non Flow Keys: <series of non Flow Keys>
     
        Template Entry C:
         Outgoing Transport Session Information (to Collector#2):
           Source IP: <IPFIX Mediator IP address>
           Destination IP: <IPFIX Collector#2 IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
         Template Id: 257
           Flow Keys: <series of Flow Keys>
           Non Flow Keys: <series of non Flow Keys>
     
        Template Entry D:
         Outgoing Transport Session Information (to Collector#3):
           Source IP: <IPFIX Mediator IP address>
           Destination IP: <IPFIX Collector#3 IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
           Template Id: 257
           Flow Keys: <series of Flow Keys>
     
     
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           Non Flow Keys: <series of non Flow Keys>
     
        The Template Mapping corresponding to figure B can be displayed
        as:
     
           Template Entry A   <----> Template Entry B
           Template Entry A   <----> Template Entry C
           Template Entry A   <----> Template Entry D
     
        Alternatively, the Template Mapping may be optimized as:
     
                                  +--> Template Entry B
                                  |
            Template Entry A   <--+--> Template Entry C
                                  |
                                  +--> Template Entry D
     
        Note that all examples use Transport Sessions based on the SCTP
        protocol, as simplified use cases.  However, the protocol would
        be important in situations such as an Intermediate Conversion
        Process doing transport protocol conversion.
     
     
     3.2.2. Template Management With New Template Records
     
        The second case is a situation where the IPFIX Mediator
        generates new (Options) Template Records as a result of the
        Intermediate Process.
     
        In such a situation, the IPFIX Mediator doesn't need to maintain
        a Template Mapping, as it generates its own series of (Options)
        Template Records.  However, the following special case might
        still require a Template Mapping, i.e. a situation where the
        IPFIX Mediator, typically containing an Intermediate Conversion
        Process, Intermediate Aggregation Process [IPFIX-MED-AGGR], or
        Intermediate Anonymization Process in case of black-marker
        Anonymization [RFC6235], generates new (Options) Template
        Records based on what it receives from the Exporter(s), and
        based on the Intermediate Process function.  In such a case,
        it's interesting to keep the correlation between the received
        (Options) Template Records and exported Derived (Options)
        Template Records in the Template Mapping.
     
        Therefore, the IPFIX Mediator MAY maintain a Template Mapping
        composed of received (Options) Template Records and exported
        derived Options) Template Records:
     
     
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          - for each received (Options) Template Record: Template
            Record Flow Keys and non Flow Keys, Template ID,
            Observation Domain, and Transport Session Information
     
          - for each exported derived Options) Template Record:
            Template Record Flow Keys and non Flow Keys, Template ID,
            Collector, Observation Domain, and Transport Session
            Information
     
       If an IPFIX Mediator receives an IPFIX Withdrawal Message for a
       (Options) Template Record that is not used anymore as the basis
       of an inferred (Options) Template Record(s), the IPFIX Mediator
       SHOULD export the appropriate IPFIX Withdrawal Message(s) for
       the inferred (Options) Template Record on the outgoing Transport
       Session, and remove the corresponding entry in the Template
       Mapping.
     
       The following two examples illustrate this.
     
       First, consider an IPFIX Mediator hosting an Intermediate
       Aggregation Process that generates time-series traffic octet
       counts per source IP address (as in the example in section 8.1
       of [IPFIX-MED-AGGR]).  Here, the Intermediate Process accepts
       Flow Records fitting any Template, discards all Information
       Elements other than the sourceIPv[46]Address and
       octetDeltaCount, aggregates these across all Original Exporters
       in a given regular time interval, and exports Flow Records
       according to a Template Record containing
       flowStartTimeMilliseconds, flowEndTimeMilliseconds,
       sourceIPv[46]Address, and octetDeltaCount.
     
       In this case, no Template Mapping is necessary.  New Templates
       and Template Withdrawals in the Transport Sessions from the
       Original Exporters are handled as they would be at any
       Collecting Process.  Records according to Templates which do not
       contain at least a timestamp, sourceIPv[46]Address, and
       octetDeltaCount IE are simply discarded by the Collector.
     
       Next, consider a more generic case of this Intermediate
       Aggregation Process, which creates time-series aggregates across
       all Original Exporters, imposing a time interval but keeping a
       subset of the incoming Flow Key received from the Original
       Exporter.  In this case, a Template Mapping is necessary, as
       there is a relationship between incoming and outgoing Templates.
     
        .--------. tid 256
     
     
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        |IPFIX   |
        |Exporter|----+
        |#1      |    |
        '--------'    |
        .--------.    |          .----------.              .---------.
        |IPFIX   |    '--------->|          |              |         |
        |Exporter|-------------->|IPFIX     |------------->|IPFIX    |
        |#2      | tid 257       |Mediator  |tid 256       |Collector|
        '--------'    +--------->|          |    257       |         |
        .--------.    |          '----------'              '---------'
        |IPFIX   |    |
        |Exporter|----'
        |#3      | tid 257
        '--------'
     
             Figure C: Intermediate Aggregation Process Example
     
       In Figure C, above, the Mediator accepts a Template Record
       containing only the sourceIPv4Address as the Flow Key from
       Exporters 1 and 2, and a Template Record containing only the
       destinationIPv4Address as the Flow Key from exporter 3.  It
       exports time-series source aggregates as Template ID 256, and
       time-series destination aggregates as Template ID 257. The
       Template Entries in this case are as follows:
     
        Template Entry A:
         Incoming Transport Session Information (from Exporter#1):
           Source IP: <Exporter#1 export IP address>
           Destination IP: <IPFIX Mediator IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
         Template Id: 256
           Flow Keys: sourceIPv4Address
           Non Flow Keys: octetDeltaCount, [others]
     
        Template Entry B:
         Incoming Transport Session Information (from Exporter#2):
           Source IP: <Exporter#2 export IP address>
           Destination IP: <IPFIX Mediator IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
         Template Id: 257
           Flow Keys: sourceIPv4Address
     
     
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           Non Flow Keys: octetDeltaCount, [others]
     
        Template Entry C:
         Incoming Transport Session Information (from Exporter#3):
           Source IP: <Exporter#3 export IP address>
           Destination IP: <IPFIX Mediator IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
         Template Id: 257
           Flow Keys: destinationIPv4Address
           Non Flow Keys: octetDeltaCount, [others]
     
        Template Entry D:
         Outgoing Transport Session Information (to IPFIX Collector):
           Source IP: <IPFIX Mediator export IP address>
           Destination IP: <IPFIX Collector IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
           Template Id: 256
           Flow Keys: sourceIPv4Address
           Non Flow Keys: octetDeltaCount
     
        Template Entry E:
         Outgoing Transport Session Information (to IPFIX Collector):
           Source IP: <IPFIX Mediator export IP address>
           Destination IP: <IPFIX Collector IP address>
           Protocol: SCTP
           Source Port: <source port>
           Destination Port: 4739 (IPFIX)
         Observation Domain Id: <Observation Domain ID>
           Template Id: 257
           Flow Keys: destinationIPv4Address
           Non Flow Keys: octetDeltaCount
     
        The Template Mapping corresponding to figure C can be displayed
        as:
     
           Template Entry A   <----> Template Entry D
           Template Entry B   <----> Template Entry D
           Template Entry C   <----> Template Entry E
     
        Note that all examples use Transport Sessions based on the SCTP
        protocol, as simplified use cases.  However, the protocol would
     
     
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        be important in situations such as an Intermediate Conversion
        Process doing transport protocol conversion.
     
     
     3.3. Time Management
     
        The IPFIX Message Header "Export Time" field is the time in
        seconds since 0000 UTC Jan 1, 1970, at which the IPFIX Message
        leaves the IPFIX Mediator.  However, in the specific case of an
        IPFIX Mediator containing an Intermediate Conversion Process,
        the IPFIX Mediator MAY keep the export time received from the
        incoming Transport Session.
     
        It is RECOMMENDED that Mediators handle time using absolute
        timestamps (e.g. flowStartSeconds, flowStartMilliseconds,
        flowStartNanoseconds), which are specified relative to the UNIX
        epoch (00:00 UTC 1 Jan 1970), where possible, rather than
        relative timestamps (e.g. flowStartSysUpTime,
        flowStartDeltaMicroseconds), which are specified relative to
        protocol structures such as system initialization or message
        export time.
     
        The latter are difficult to manage for two reasons.  First,
        they require constant translation, as the system
        initialization time of an intermediate system and the export
        time of an intermediate message will change across mediation
        operations.  Further, relative timestamps introduce range
        problems. For example, when using the
        flowStartDeltaMicroseconds and flowEndDeltaMicroseconds
        Information Elements [RFC5102], the Data Record must be
        exported within a maximum of 71 minutes after its creation.
        Otherwise, the 32-bit counter would not be sufficient to
        contain the flow start time offset.  Those time constraints
        might be incompatible with some of the Intermediate Processes:
        Intermediate Aggregation Process (temporal) and Intermediate
        Correlation Process, for example.
     
        When an Intermediate Aggregation Process aggregates information
        from different Flow Records, the typical reporting times SHOULD
        be the minimum of the start times and the maximum of the end
        times.  However, if the Flow Records do not overlap, i.e. if
        there is a time gap between the times in the Flow Records, then
        the report may be inaccurate.  The IPFIX Mediator is only
        reporting what it knows, on the basis of the information made
        available to it - and there may not have been any data to
        observe during the gap.  Then again, if there is an overlap in
        timestamps, there's the potential of double-accounting:
     
     
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        different Observation Points may have observed the same traffic
        simultaneously.  Therefore, as there is not a single rule that
        fits all different situations, a complete specification of the
        precise rules of applying Flow Record timestamps at IPFIX
        Mediators is out of the scope of this document.
     
        Note that [IPFIX-MED-AGGR] provides additional specifications
        for handling of timestamps at an Intermediate Aggregation
        Process.
     
     
     3.4. Observation Point Management
     
        Depending on the use case, the Collector in an Exporter-
        Mediator-Collector structure model may need to receive the
        Original Observation Point(s), otherwise it may wrongly conclude
        that the IPFIX Device exporting the Flow Records to him, i.e.
        the IPFIX Mediator, directly observed the packets that generated
        the Flow Records.  Two new Information Elements are introduced
        to solve this use case: originalExporterIPv4Address and
        originalExporterIPv6Address.  Practically, the Original
        Exporters will not exporting these Information Elements.
        Therefore, the Intermediate Process SHOULD report the Original
        Observation Point(s) to the best of its knowledge.  Note that
        the Configuration Data Model for IPFIX and PSAMP [IPFIX-CONF]
        may help.
     
        In the IPFIX Mediator, the Observation Point(s) may be
        represented by:
            - A single Original Exporter (represented by the
            originalExporterIPv4Address or originalExporterIPv6Address
            Information Elements)
            - A list of Original Exporter (represented by the
            originalExporterIPv4Address or originalExporterIPv6Address
            Information Elements)
            - Any combination or list of Information Elements
            representing Observation Points. For example:
                o  A list of Original Exporter interface(s)
                (represented by the originalExporterIPv4Address or
                originalExporterIPv6Address, the ingressInterface
                and/or egressInterface Information Elements,
                respectively)
                o  A list of Original Exporter line card (represented
                by the originalExporterIPv4Address or
                originalExporterIPv6Address, the lineCardId Information
                Elements, respectively)
     
     
     
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        Some Information Elements characterizing the Observation Point
        may be added.  For example, the flowDirection Information
        Element specifies the direction of the observation, and, as
        such, characterizes the Observation Point.
     
        Any combination of the above examples is possible.  For example,
        in case of an Intermediate Aggregation Process, an Original
        Observation Point can be composed of:
              exporterIPv4Address 192.0.2.1
              exporterIPv4Address 192.0.2.2,
                       interface ethernet 0, direction ingress
                       interface ethernet 1, direction ingress
                       interface serial 1, direction egress
                       interface serial 2, direction egress
              exporterIPv4Address 192.0.2.3,
                       lineCardId 1, direction ingress
     
        If the Original Observation Point is composed of a list, then
        the IPFIX Structured Data [RFC6313] MUST be used to export it
        from the IPFIX Mediator.
     
        The most generic way to export the Original Observation Point is
        to use a subTemplateMultiList, with the semantic "exactlyOneOf".
        Taking the previous example, the following encoding can be used:
     
                 Template Record 257: exporterIPv4Address
                 Template Record 258: exporterIPv4Address, basicList of
                                    ingressInterface, flowDirection
                 Template Record 259: exporterIPv4Address, lineCardId,
                                    flowDirection
     
        The Original Observation Point is modeled with the Data Records
        corresponding to either Template Record 1, Template Record 2, or
        Template Record 3 but not more than one of these ("exactlyOneOf"
        semantic).  This implies that the Flow was observed at exactly
        one of the Observation Points reported.
     
        When an IPFIX Mediator receives Flow Records containing the
        Original Observation Point Information Element, i.e.
        originalExporterIPv6Address or originalExporterIPv4Address, the
        IPFIX Mediator SHOULD NOT modify its value(s) when composing new
        Flow Records in the general case.   Known exceptions include
        anonymization per [RFC6235] section 7.2.4 and an Intermediate
        Correlation Process rewriting addresses across NAT.  In other
        words, the Original Observation Point should not be replaced the
     
     
     
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        IPFIX Mediator Observation Point.  The daisy chain of (Exporter,
        Observation Point) representing the path the Flow Records took
        from the Exporter to the top Collector in the Exporter-
        Mediator(s)-Collector structure model is out of the scope of
        this specification.
     
     
     
     3.4.1. Observation Domain Management
     
        In any case, the Observation Domain ID of any IPFIX Message
        containing Flow Records relevant to no particular Observation
        Domain, or to multiple Observation Domains, MUST have an
        Observation Domain ID of 0, as in section 3.1 above, and section
        3.1 of [RFC5101bis].
     
        IPFIX Mediators that do not change (Options) Template Records
        MUST maintain a Template Mapping, as detailed in section 3.2.1,
        to ensure that the combination of Observation Domain IDs and
        Template IDs do not collide on export.
     
        For IPFIX Mediators that export New (Options) Template Records
        unchanged, as in section 3.2.2, there are two options for
        Observation Domain ID management.  The first and simplest of
        these is to completely decouple exported Observation Domain IDs
        from received Observation Domain IDs; the IPFIX Mediator, in
        this case, comprises its own set of Observation Domain(s)
        independent of the Observation Domain(s) of the Original
        Exporters.
     
        The second option is to provide or maintain a Template Mapping
        for received (Options) Template Records and exported inferred
        (Options) Template Records, along with the appropriate
        Observation Domain IDs per Transport Session, which ensures that
        the combination of Observation Domain IDs and Template IDs do
        not collide on export.
     
        In some cases where the IPFIX Message Header can't contain a
        consistent Observation Domain for the entire IPFIX Message, but
        the Flow Records exported from the IPFIX Mediator should anyway
        contain the Observation Domain of the Original Exporter, the
        (Options) Template Record must contain the
        originalObservationDomainId Information Element.  When an IPFIX
        Mediator receives Flow Records containing the
        originalObservationDomainId Information Element, the IPFIX
        Mediator MUST NOT modify its value(s) when composing new Flow
        Records with the originalObservationDomainId Information
     
     
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        Element.
     
     
     
     3.5. Specific Reporting Requirements
     
        Some specific Options Templates and Options Template Records are
        necessary to provide extra information about the Flow Records
        and about the Metering Process.
     
        The Options Template Records defined in these subsections, which
        impose some constraints on the Metering Process and Exporting
        Process implementations in Intermediate Processes, MAY be
        implemented.  If implemented, the specific Option Templates
        SHOULD be implemented as specified in these subsections.
     
        The minimum set of Information Elements is always specified in
        these specific IPFIX Options Templates.  Nevertheless, extra
        Information Elements may be used in these specific Options
        Templates.
     
     
     3.5.1. The Flow Keys Options Template
     
        Exactly like the IPFIX protocol [RFC5101bis], the Flow Keys
        Option Template specifies the structure of a Data Record for
        reporting the Flow Keys of reported Flows.  A Flow Keys Data
        Record extends a particular Template Record that is referenced
        by its templateId identifier.  The Template Record is extended
        by specifying which of the Information Elements contained in the
        corresponding Data Records describe Flow properties that serve
        as Flow Keys of the reported Flow.
     
        The Flow Keys Option Template SHOULD contain the following
        Information Elements that are defined in [RFC5102]
     
           templateId              An identifier of a Template.  This
                                   Information Element MUST be defined
                                   as a Scope Field.
     
           flowKeyIndicator        Bitmap with the positions of the Flow
                                   Keys in the Data Records.
        When any Intermediate Process changes the Flow Keys, the Flow
        Keys Option Template MUST include the new set of Flow Keys.
        Typically, an Intermediate Aggregation Process keeps or reduces
        the number of Flow Keys.  However, the number of Flow Keys may
     
     
     
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        increase when the Original Exporter or/and Original Observation
        Point is/are added.
     
     3.5.2. IPFIX Protocol Options Template
     
        The "Metering Process Statistics Options Template", "The
        Metering Process Reliability Statistics Options Template", and
        "The Exporting Process Reliability Statistics Options Template",
        as specified in [RFC5101bis], SHOULD be implemented on the IPFIX
        Mediator.
     
        Refer to the document specifying a particular Intermediate
        Process type for specific values for these Options Template
        Records.  For example, in case of an Intermediate Aggregation
        Process, [IPFIX-MED-AGGR] specifies which values to insert into
        the fields of "Metering Process Statistics Options Template",
        "The Metering Process Reliability Statistics Options Template",
        and "The Exporting Process Reliability Statistics Options
        Template"
     
     
     3.5.3. IPFIX Mediator Options Template
     
        There is no need for a specific Options Template for the IPFIX
        Mediator; instead, each Intermediate Process type requires some
        particular metadata.  For example, a specification of IPFIX flow
        Anonymization including an Options Template for the export of
        metadata about Anonymized flows is described in [RFC6235]; when
        Anonymizing Flows Records, IPFIX Mediators SHOULD add the
        Options Template specified therein to annotate the exported
        data.
     
        Transport Session Management SCTP [RFC4960] using the PR-SCTP
        extension specified in [RFC3758] MUST be implemented by all
        compliant IPFIX Mediator implementations.  UDP [RFC768] MAY also
        be implemented by compliant IPFIX Mediator implementations.  TCP
        [RFC793] MAY also be implemented by IPFIX Mediator compliant
        implementations.
     
        PR-SCTP SHOULD be used in deployments where IPFIX Mediators and
        Collectors are communicating over links that are susceptible to
        congestion.  PR-SCTP is capable of providing any required degree
        of reliability.
     
        TCP MAY be used in deployments where IPFIX Mediators and
        Collectors communicate over links that are susceptible to
        congestion, but PR-SCTP is preferred due to its ability to limit
     
     
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        back pressure on Exporters and its message versus stream
        orientation.
     
        UDP MAY be used, although it is not a congestion-aware protocol.
        However, in this case, the IPFIX traffic between IPFIX Mediator
        and Collector MUST run in an environment where IPFIX traffic has
        been provisioned for, or is contained through some other means.
     
     
     3.6. The Collecting Process's Side
     
        An IPFIX Mediator produces IPFIX Messages understandable by a
        IPFIX-compliant Collector, with the additional specifications in
        IPFIX Structured Data [RFC6313].
     
        Therefore the Collecting Process on the top Collector MUST
        support the IPFIX protocol [RFC5101bis] and the IPFIX Structured
        Data [RFC6313].
     
     
     3.7. Configuration Management
     
        In some cases such as an Intermediate Aggregation Process
        aggregating Flow Records from multiple Original Exporters, a
        consistent configuration of the Metering Processes and Exporting
        Processes on these Original Exporters offers some advantages.
        For example, consistent active timeout, inactive timeout, and/or
        consistent export time allows the number of the Flow Records per
        period of time to be compared.  For example, consistent Sampling
        algorithm and parameters might allow Flow Records accuracy to be
        compared.
     
        While this is tempting to include all configuration parameters
        in Flow Records for the IPFIX Mediator to draw its own
        conclusion, the consistency of the configuration should be
        verified out of band, with the MIB modules ([RFC5815bis] and
        [PSAMP-MIB]) or with the Configuration Data Model for IPFIX and
        PSAMP [IPFIX-CONF]
     
     
     4. New Information Elements
     
       Three new Information Elements are requested in this
       specifications: originalExporterIPv4Address,
       originalExporterIPv6Address, and originalObservationDomainId.
       See Section 6.1. , Section 6.2. , and Section 6.3. ,
       respectively, for the formal definitions.
     
     
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     5. Security Considerations
     
        The same security considerations as for the IPFIX Protocol
        [RFC5101bis] apply.
     
        As they act as both IPFIX Collecting Processes and Exporting
        Processes, the Security Considerations for IPFIX Protocol
        [RFC5101bis] also apply to Mediators.  The Security
        Considerations for IPFIX Files [RFC5655] also apply to IPFIX
        Mediators that write IPFIX Files or use them for internal
        storage.  However, there are a few specific considerations that
        IPFIX Mediator implementations must also take into account.
     
        By design, IPFIX Mediators are "men-in-the-middle": they
        intercede in the communication between an Original Exporter (or
        another upstream Mediator) and a downstream Collecting Process.
        This has two important implications for the level of
        confidentiality provided across an IPFIX Mediator, and the
        ability to protect data integrity and Original Exporter
        authenticity across a Mediator. These are addressed in more
        detail in the Security Considerations for Mediators in [IPFIX-
        MED-FMWK].
     
        Note that, while Mediators can use the exporterCertificate and
        collectorCertificate Information Elements defined in [RFC5655]
        as described in section 9.3 of [IPFIX-MED-FMWK] to export
        information about X.509 identities in upstream TLS-protected
        Transport Sessions, this mechanism cannot be used to provide
        true end-to-end assertions about a chain of IPFIX Mediators: any
        Mediator in the chain can simply falsify the information about
        upstream Transport Sessions  In situations where information
        about the chain of mediation is important, it must be determined
        out of band.
     
     
     6. IANA Considerations
     
      This document specifies three new IPFIX Information Elements: the
      applicationDescription, applicationTag and the applicationName.
     
      New Information Elements to be added to the IPFIX Information
      Element registry at [IANA-IPFIX] are listed below.
     
      XML specifications of these elements can be found in Appendix A.
     
     
     
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      EDITOR'S NOTE: please change the TBD1, TBD2, and TBD3, with the
      IANA newly assigned numbers. Note that the XML specification in
      Appendix A must also be updated with the elementId values
      allocated.
     
     6.1. originalExporterIPv4Address
     
      Name: originalExporterIPv4Address
      Description:
        The IPv4 address used by the Exporting Process on the Original
        Exporter. This is used by an IPFIX Mediator Exporting Process
        to identify the Original Exporter.
      Abstract Data Type: ipv4Address
      Data Type Semantics: identifier
      ElementId: TBD1
      Status: current
     
     
     6.2. originalExporterIPv6Address
     
      Name: originalExporterIPv6Address
      Description:
        The IPv6 address used by the Exporting Process on the Original
        Exporter. This is used by the IPFIX Mediator Exporting Process
        to identify the Original Exporter.
      Abstract Data Type: ipv6Address
      Data Type Semantics: identifier
      ElementId: TBD2
      Status: current
     
     
     6.3. originalObservationDomainId
     
      Name: originalObservationDomainId
      Description:
         An identifier of the Observation Domain on the Original
         Exporter, where the metered IP packets are observed. This is
         used by the IPFIX Mediator Exporting Process to identify an
         Observation Domain as received from the Original Exporter.
      Abstract Data Type: unsigned32
     Data Type Semantics: identifier
     ElementId: TBD3
     Status: current
     
     
     
     
     
     
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     7. References
     
     7.1. Normative References
     
        [RFC2119] S. Bradner, Key words for use in RFCs to Indicate
                Requirement Levels, BCP 14, RFC 2119, March 1997
     
        [RFC3758] Stewart, R., Ramalho, M, Xie, Q., Tuexen, M., and P.
                Conrad, "Stream Control Transmission Protocol (SCTP),
                Partial Reliability Extension", May 2004
     
        [RFC4960] Stewart, R., Ed., "Stream Control Transmission
                Protocol", RFC 4960, September 2007.
     
        [RFC5102] Quittek, J., Bryant, S., Claise, B., Aitken, P., and
                J. Meyer, "Information Model for IP Flow Information
                Export", RFC 5102, January 2008.
     
        [RFC5655] Trammell, B., Boschi, E., Mark, L., Zseby, T., and A.
                Wagner, "Specification of the IP Flow Information
                Export (IPFIX) File Format", RFC 5655, October 2009.
     
        [RFC6313] Claise, B., Dhandapani, G., Aitken, P., and S. Yates,
                "Export of Structured Data in IP Flow Information
                Export (IPFIX)", RFC6313, July 2011.
     
        [IPFIX-MED-FLOWSEL] D'antonio, S., Zseby, T., Henke, C. and L.
                Peluso, "Flow Selection Techniques", draft-ietf-ipfix-
                flow-selection-tech-09.txt, Internet-Draft work in
                progress, November 2011.
     
        [IPFIX-MED-AGGR] Trammell, B., Boschi, E., A. Wagner, and B.
                Claise, "Exporting Aggregated Flow Data using the IP
                Flow Information Export (IPFIX) Protocol", draft-
                trammell-ipfix-a9n-03.txt, Internet-Draft work in
                progress, June 2011.
     
        [PSAMP-MIB] Dietz, T., Claise, B., and J. Quittek "Definitions
                of Managed Objects for Packet Sampling", draft-ietf-
                ipfix-psamp-mib-04.txt, Internet-Draft work in
                progress, October 2011.
     
        [IPFIX-CONF] Muenz, G., Claise, B., and P. Aitken "Configuration
                Data Model for IPFIX and PSAMP", draft-ietf-ipfix-
                configuration-model-10, Internet-Draft work in
                progress, July 2011.
     
     
     
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        [RFC5101bis] Claise, B., and B. Trammell, "Specification of the
                IP Flow Information eXport (IPFIX) Protocol for the
                Exchange of IP Traffic Flow Information", draft-ietf-
                ipfix-protocol-rfc5101bis-00, Work in Progress,
                November 2011.
     
        [RFC5815bis] Dietz, T., Kobayashi, A., Claise, B., and G. Muenz,
                "Definitions of Managed Objects for IP Flow Information
                Export", draft-ietf-ipfix-rfc5815bis-00.txt, Work in
                Progress, April 2010.
     
     
     
     7.2. Informative References
     
     
        [RFC768] Postel, J., "User Datagram Protocol", STD 6, RFC 768,
                August 1980.
     
        [RFC793] Postel, J., "Transmission Control Protocol", STD 7, RFC
                793, September 1981.
     
        [RFC3917] Quittek, J., Zseby, T., Claise, B., and S. Zander,
                "Requirements for IP Flow Information Export", RFC
                3917, October 2004
     
        [RFC3954] Claise, B. (Ed), "Cisco Systems NetFlow Services
                Export Version 9", RFC 3954, October 2004
     
        [RFC5470] Sadasivan, G., Brownlee, N., Claise, B., and J.
                Quittek, "Architecture Model for IP Flow Information
                Export", RFC5470, March 2009
     
        [RFC5472] Zseby, T., Boschi, E., Brownlee, N., and B. Claise,
                "IP Flow Information Export (IPFIX) Applicability", RFC
                5472, March 2009
     
        [RFC5476] Claise, B., Quittek, J., and A. Johnson, "Packet
                Sampling (PSAMP) Protocol Specifications", RFC 5476,
                March 2009.
     
        [RFC5982] Kobayashi, A. (Ed), Claise, B. (Ed), "P Flow
                Information Export (IPFIX) Mediation: Problem
                Statement", RFC 5982, August 2010.
     
     
     
     
     
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     Internet-Draft     <Protocol for IPFIX Mediations>       Dec 2011
     
     
        [IPFIX-MED-FMWK] Kobayashi, A., Claise, B., Muenz, G., and K.
                Ishibashi, "IPFIX Mediation: Framework", RFC 6183,
                April 2011.
     
        [RFC6235] Boschi, E., Trammell, B. "IP Flow Anonymization
                Support", RFC 6235, May 2011.
     
        [IANA-IPFIX] http://www.iana.org/assignments/ipfix/ipfix.xhtml
     
     
        Acknowledgments
     
        We would like to thank the IPFIX contributors and specifically
        Paul Aitken for his thorough review.
     
     
     
     8. Author's Addresses
     
        Benoit Claise
        Cisco Systems, Inc.
        De Kleetlaan 6a b1
        Diegem 1813
        Belgium
     
        Phone: +32 2 704 5622
        Email: bclaise@cisco.com
     
     
        Atsushi Kobayashi
        NTT Information Sharing Platform Laboratories
        3-9-11 Midori-cho
        Musashino-shi, Tokyo  180-8585
        Japan
     
        Phone: +81-422-59-3978
        Email: akoba@nttv6.net
        URI:   http://www3.plala.or.jp/akoba/
     
     
        Brian Trammell
        ETH Zurich
        Gloriastrasse 35
        8092 Zurich
        Switzerland
     
        Phone: +41 44 632 70 13
     
     
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        EMail: trammell@tik.ee.ethz.ch
     
     
     
      Appendix A.  Additions to XML Specification of IPFIX Information
      Elements
     
        This appendix contains additions to the machine-readable
        description of the IPFIX information model coded in XML in
        Appendix A and Appendix B in [RFC5102].  Note that this appendix
        is of informational nature, while the text in Section 6.
        (generated from this appendix) is normative.
     
        The following field definitions are appended to the IPFIX
        information model in Appendix A of [RFC5102].
     
        <field name="originalExporterIPv4Address"
                 dataType="ipv4Address"
                 group="config"
                 elementId="TBD1" applicability="all" status="current">
            <description>
              <paragraph>
                The IPv4 address used by the Exporting Process on the
                Original Exporter. This is used by an IPFIX Mediator
                Exporting Process to identify the Original Exporter.
              </paragraph>
            </description>
          </field>
     
     
        <field name="originalExporterIPv6Address"
                 dataType="ipv6Address"
                 group="config"
                 elementId="TBD2" applicability="all" status="current">
            <description>
              <paragraph>
                The IPv6 address used by the Exporting Process on the
                Original Exporter. This is used by the IPFIX Mediator
                Exporting Process to identify the Original Exporter.
              </paragraph>
            </description>
          </field>
     
        <field name="originalObservationDomainId"
                 dataType="unsigned32"
                 group="config"
                 elementId="TBD3" applicability="all" status="current">
     
     
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            <description>
              <paragraph>
                An identifier of the Observation Domain on the Original
                Exporter, where the metered IP packets are observed.
                This is used by the IPFIX Mediator Exporting Process to
                identify an Observation Domain as received from the
                Original Exporter.
              </paragraph>
            </description>
          </field>
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
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