One document matched: draft-ietf-i2rs-traceability-10.xml


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<rfc category="info" docName="draft-ietf-i2rs-traceability-10"
     ipr="trust200902">
  <front>
    <title abbrev="I2RS Traceability">Interface to the Routing System
    (I2RS) Traceability: Framework and Information Model</title>

    <author fullname="Joe Clarke" initials="J." surname="Clarke">
      <organization abbrev="Cisco">Cisco Systems, Inc.</organization>

      <address>
        <postal>
          <street>7200-12 Kit Creek Road</street>

          <city>Research Triangle Park</city>

          <region>NC</region>

          <code>27709</code>

          <country>US</country>
        </postal>

        <phone>+1-919-392-2867</phone>

        <email>jclarke@cisco.com</email>
      </address>
    </author>

    <author fullname="Gonzalo Salgueiro" initials="G."
            surname="Salgueiro">
      <organization abbrev="Cisco">Cisco Systems, Inc.</organization>

      <address>
        <postal>
          <street>7200-12 Kit Creek Road</street>

          <city>Research Triangle Park</city>

          <region>NC</region>

          <code>27709</code>

          <country>US</country>
        </postal>

        <email>gsalguei@cisco.com</email>
      </address>
    </author>

    <author fullname="Carlos Pignataro" initials="C."
            surname="Pignataro">
      <organization abbrev="Cisco">Cisco Systems, Inc.</organization>

      <address>
        <postal>
          <street>7200-12 Kit Creek Road</street>

          <city>Research Triangle Park</city>

          <region>NC</region>

          <code>27709</code>

          <country>US</country>
        </postal>

        <email>cpignata@cisco.com</email>
      </address>
    </author>

    <date/>

    <area>Routing</area>

    <workgroup>I2RS</workgroup>

    <keyword>I2RS</keyword>

    <keyword>I2RS Traceability</keyword>

    <keyword>Traceability</keyword>

    <abstract>
      <t>This document describes a framework for traceability in the
      Interface to the Routing System (I2RS) and information model for
      that framework. It specifies the motivation, requirements, use
      cases, and defines an information model for recording
      interactions between elements implementing the I2RS protocol.
      This framework provides a consistent tracing interface for
      components implementing the I2RS architecture to record what was
      done, by which component, and when. It aims to improve the
      management of I2RS implementations, and can be used for
      troubleshooting, auditing, forensics, and accounting
      purposes.</t>
    </abstract>
  </front>

  <middle>
    <section anchor="intro" title="Introduction">
      <t>The architecture for the Interface to the Routing System
      (<xref target="I-D.ietf-i2rs-architecture"/>) specifies that
      I2RS Clients wishing to retrieve or change routing state on a
      routing element MUST authenticate to an I2RS Agent. The I2RS
      Client will have a unique identity it provides for
      authentication, and should provide another, opaque identity
      for applications communicating through it. The
      programming of routing state will produce a return code
      containing the results of the specified operation and associated
      reason(s) for the result. All of this is critical information to
      be used for understanding the history of I2RS interactions.</t>

      <t>This document defines the framework necessary
      to trace those interactions between the I2RS Client and I2RS Agent.
      It goes on to describe use cases for traceability within I2RS.
      Based on these use cases, the document proposes an information
      model and reporting requirements to provide for effective
      recording of I2RS interactions. In this context, effective
      troubleshooting means being able to identify what operation was
      performed by a specific I2RS Client via the I2RS Agent,
      what was the result of the operation, and when that operation
      was performed.</t>
    </section>

    <section anchor="terminology" title="Terminology and Conventions">
      <t>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 <xref target="RFC2119"/>.</t>

      <t>The architecture specification for I2RS <xref
      target="I-D.ietf-i2rs-architecture"/> defines additional terms
      used in this document that are specific to the I2RS domain, such
      as "I2RS Agent", "I2RS Client", etc. The reader is expected to
      be familiar with the terminology and concepts defined in <xref
      target="I-D.ietf-i2rs-architecture"/>.</t>
    </section>

    <section anchor="motivation" title="Motivation">
      <t>As networks scale and policy becomes an increasingly
      important part of the control plane that creates and maintains
      the forwarding state, operational complexity increases as well.
      I2RS offers more granular and coherent control over policy and
      control plane state, but it also removes or reduces the locality
      of the policy that has been applied to the control plane at any
      individual forwarding device. The ability to automate and
      abstract even complex policy-based controls highlights the need
      for an equally scalable traceability function to provide
      recording at event-level granularity of the evolution of the routing
      system compliant with the
      requirements of I2RS (Section 5 of <xref
      target="I-D.ietf-i2rs-problem-statement"/>).</t>
    </section>

    <section anchor="use_cases" title="Use Cases">
      <t>An obvious motivation for I2RS traceability is the need to
      troubleshoot and identify root-causes of problems in these
      increasingly complex routing systems. For example, since I2RS is
      a high-throughput multi-channel, full duplex and highly
      responsive interface, I2RS Clients may be performing a large
      number of operations on I2RS Agents concurrently or at nearly
      the same time and quite possibly in very rapid succession. As
      these many changes are made, the network reacts accordingly.
      These changes might lead to a race condition, performance
      issues, data loss, or disruption of services. In order to
      isolate the root cause of these issues it is critical that a
      network operator or administrator has visibility into what
      changes were made via I2RS at a specific time.</t>

      <t>Some network environments have strong auditing requirements
      for configuration and runtime changes. Other environments have
      policies that require saving logging information for operational
      or regulatory compliance considerations. These requirements
      therefore demand that I2RS provides an account of changes made
      to network element routing systems.</t>

      <t>As I2RS becomes increasingly pervasive in routing
      environments, a traceability model that supports controllable trace
      log retention using a standardized structured data format offers
      significant advtanges, such as the ability to create common tools
      supporting automated testing,
      and facilitates the following use cases:</t>

      <t><list style="symbols">
	  <t>Real-time monitoring and troubleshooting of router events;</t>

          <t>Automated event correlation, trend analysis, and anomaly
          detection;</t>

          <t>Offline (manual or tools-based) analysis of router state evolution
	  from the retained trace logs;</t>

	  <t>Enhanced network audit, management and forensic analysis
          capabilities;</t>

          <t>Improved accounting of routing system operations; and</t>

	  <t>Providing a standardized format for incident reporting and
	  test logging.</t>
        </list></t>
    </section>

    <section anchor="information_model" title="Information Model">
      <t>These sections describe the I2RS traceability information model
      and the detail corresponding to each of the fields to be logged.</t>

      <section anchor="info_framework"
               title="I2RS Traceability Framework">
        <t>This section describes a framework for I2RS traceability
	based on the I2RS Architecture.</t>

        <t>The interaction between the optional network application that
	drives Client activity, I2RS
        Client, I2RS Agent, the Routing System and the data captured
        in the I2RS trace log is shown in <xref
        target="i2rs_interaction_trace"/>.<vspace
        blankLines="35"/></t>

        <figure align="center" anchor="i2rs_interaction_trace"
                title="I2RS Interaction Trace Log Capture">
          <artwork align="center"><![CDATA[
           +---------------+
      +----------------+   |
      |Application     |   |
      |..............  |   |  0 or more Applications
      | Application ID |   +
      +----------------+
             ^
             |
             |
             v
          +-------------+
      +-------------+   |
      |I2RS Client  |   |
      |.............|   |  1 or more Clients
      |  Client ID  |   +
      +-------------+
             ^
             |
             |
             v
      +-------------+                 +-----------------------------+
      |I2RS Agent   |---------------->|Trace Log                    |
      |             |                 |.............................|
      +-------------+                 |Log Entry  [1 .. N]          |
            |  ^                      |.............................|
            |  |                      |Event ID                     |
            |  |                      |Starting Timestamp           |
            |  |                      |Request State                |
            |  |                      |Client ID                    |
            |  |                      |Client Priority              |
            |  |                      |Secondary ID                 |
Operation + |  | Result Code          |Client Address               |
 Op Data    |  |                      |Requested Operation          |
            |  |                      |Applied Operation            |
            |  |                      |Operation Data Present       |
            |  |                      |Requested Operation Data     |
            |  |                      |Applied Operation Data       |
            |  |                      |Transaction ID               |
            |  |                      |Result Code                  |
            |  |                      |Ending Timestamp             |
            |  |                      |Timeout Occurred             |
            v  |                      |End Of Message               |
      +-------------+                 +-----------------------------+
      |Routing      |
      |System       |
      +-------------+
]]></artwork>
        </figure>
      </section>

      <section anchor="info_required"
               title="I2RS Trace Log Fields">
        <t>The following fields comprise an I2RS Trace Log.  These fields
	ensure that each I2RS interaction can be properly traced back to the
	Client that made the request at a specific point in time.</t>

        <t>The list below describes the fields captured in the I2RS
        trace log.</t>

        <t><list style="hanging">
	  <t hangText="Event ID: ">This is a unique identifier for each
	      event in the I2RS trace log.  An event can be a Client
	      authenticating with the Agent, a Client to Agent operation,
	      or a Client disconnecting from an Agent.  Operation
	      events can either be logged atomically upon completion
	      (in which case they will have both a Starting and an Ending
	      Timestamp field) or they can be logged at the beginning of each
	      Request State transition.
            Since operations can occur from the same Client at the same
            time, it is important to have an identifier that can be
	    unambiguously associated to a specific entry.  If each state
	    transition is logged for an operation, the same ID
	    MUST be used for each of Request State log entries
	    In this way, the life of a request can be easily
	    followed in the I2RS trace log.  Beyond the requirement that
	    the Event ID MUST be unique for each event, the specific
	    type and value is left up to the implementation.</t>

            <t hangText="Starting Timestamp: ">The specific time
	    at which the I2RS operation enters the specified
	    Request State within the Agent.  If the log entry covers the
	    entire duration of the request, then this will be time the
	    was first received by the Agent. This field MUST be present in
	    all entries that specify the beginning of the state transition,
	    as well as those entries that log the entire duration of the
	    request.
	    The time is passed in the full <xref target="RFC3339"/> format
	    including date and offset from Coordinated Universal Time (UTC).
            Given that many I2RS operations
	    can occur in rapid succession, the
	    fractional seconds element of the timestamp MUST be used to
	    provide adequate granularity.
	    Fractional seconds SHOULD be expressed with at least three
	    significant digits in second.microsecond format.</t>

	    <t hangText="Request State: ">The state of the given operation
	    within the I2RS Agent state machine at the specified
	    Starting or Ending Timestamps.  The I2RS Agent SHOULD generate
	    a log entry at the moment a request enters and exits a
	    state.  Upon entering a new state, the log entry will have
	    a Starting Timestamp set to the time of entry and no
	    Ending Timestamp.  Upon exiting a state, the log entry will
	    have an Ending Timestamp set to the time of exit and no
	    Starting Timestamp.  The progression of the request through
	    its various states and be linked using the Event ID.
	    The states can be one of the following values:

	      <list>
	        <t>PENDING: The request has been received and queued for
		    processing.</t>
		<t>IN PROCESS: The request is currently being handled by
		    the I2RS Agent.</t>
		<t>COMPLETED: The request has reached a terminal point.</t>
	      </list>
	    </t>

	    <t>Every state transition SHOULD be logged unless doing so will put
	    an undue performance burden on the I2RS Agent.  However, an entry
	    with Request State set to COMPLETED MUST be logged for all
	    operations.  If the COMPLETED state is the only entry for a
	    given request, then it MUST have both Starting and Ending Timestamps
	    that cover the entire duration of the request from ingress to
	    the Agent until completion.</t>

            <t hangText="Client Identity: ">The I2RS Client
            identity used to authenticate the Client to the I2RS
            Agent.</t>

            <t hangText="Client Priority: ">The I2RS Client priority
            assigned by the access control model that authenticates the
            Client.  For example, this can be set by the NETCONF Access
            Control Model (NACM) as described in <xref target="RFC6536"/>.</t>

            <t hangText="Secondary Identity: ">This is an opaque
            identity that may be known to the Client from a
            controlling network application. This is used to trace
            the network application driving the actions of the Client.
            The Client may not provide this identity to the Agent if
	    there is no external network application driving the Client.
	    However, this field MUST be logged even if the Client does not
	    provide a Secondary Identity.  In that case, the field will be
	    logged with an empty value.</t>

            <t hangText="Client Address: ">This is the network address
            of the Client that connected to the Agent. For example,
            this may be an IPv4 or IPv6 address.</t>

            <t hangText="Requested Operation: ">This is the I2RS operation
            that was requested to be performed. For example, this may be an
            add route operation if a route is being inserted into a routing
            table.  This may not be the operation that was actually applied
            to the Agent.</t>

	    <t>In the case of a Client authenticating to the Agent, the
	    Requested Operation MUST be "CLIENT AUTHENTICATE".  In the case of
	    a Client disconnecting from the Agent, the Requested Operation
	    MUST be "CLIENT DISCONNECT".</t>

            <t hangText="Applied Operation: ">This is the I2RS operation
            that was actually performed.  This can differ from the Requested
            Operation in cases where the Agent cannot satisfy the Requested
	    Operation.  This field may not be logged unless the Request State
	    is COMPLETED.</t>

            <t hangText="Operation Data Present: ">This is a Boolean
            field that indicates whether or not addition per-Operation
            Data is present.</t>

            <t hangText="Requested Operation Data: ">This field comprises the
            data passed to the Agent to complete the desired
            operation. For example, if the operation is a route add
            operation, the Operation Data would include the route
            prefix, prefix length, and next hop information to be
            inserted as well as the specific routing table to which
            the route will be added. If Operation Data is
            provided, then the Operation Data Present field MUST
            be set to TRUE.  Some operations may not
            provide operation data.  In those cases, the
            Operation Data Present field MUST be set to FALSE, and
            this field MUST be empty.  This may not represent the
            data that was used for the operation that was actually
            applied on the Agent.</t>

	    <t>When a Client authenticates to the Agent, the
	    Requested Operation Data MUST contain the Client priority.
	    Other attributes such as credentials used for authentication
	    MAY be logged.</t>

            <t hangText="Applied Operation Data: ">This field comprises the
            data that was actually applied as part of the Applied Operation.
            If the Agent cannot satisfy the Requested Operation with the
            Requested Operation Data, then this field can differ from the
	    Requested Operation Data.  This field will be empty unless
	    Requested Operation Data was specified.  This field may not be
	    logged unless the Request State is COMPLETED.</t>

            <t hangText="Transaction ID: ">The Transaction Identity
            represents that this particular operation
            is part of a long-running I2RS transaction that can consist
            of multiple, related I2RS operations.  Using this value,
            one can relate multiple log entries together as they are
	    part of a single, overall I2RS operation.  This is an optional
	    field that may not be logged unless the event is part of a
	    long-running transaction.</t>

            <t hangText="Result Code: ">This field holds the result of
	    the operation once the Request State is COMPLETED. In the case
	    of Routing Information Base (RIB) operations, this MUST be
            the return code as specified in Section 4 of <xref
            target="I-D.ietf-i2rs-rib-info-model"/>. The operation
            may not complete with a result code in the case of a
            timeout. If the operation fails to complete, it MUST still
            log the attempted operation with an appropriate result
	    code.</t>

	    <t hangText="Timeout Occurred: ">This is a Boolean field that
	    indicates whether or not a timeout occurred in the operation.
	    When this is true, the value of the Ending Timestamp MUST be
	    set to the time the Agent recorded for the timeout
	    occurrence.  This field may not be logged unless the Request
	    State is COMPLETED.</t>

            <t hangText="Ending Timestamp: ">The specific time
	    at which the I2RS operation exits the specified Request State
	    within the I2RS Agent. If the log entry covers the entire duration
	    of the request, then this will be time the request reached a
	    terminal point within the Agent.  This field MUST be present in
            all entries that specify the ending of the state transition,
            as well as those entries that log the entire duration of the
            request.
	    The time is passed in the full
	    <xref target="RFC3339"/> format including date and offset from
	    Coordinated Universal Time (UTC).  See the description for
	    Starting Timestamp above for the proper format of Ending
	    Timestamp.</t>

            <t hangText="End Of Message: ">Each log entry SHOULD have
            an appropriate End Of Message (EOM) indicator. See section
            <xref target="eom"/> below for more details.</t>
          </list></t>
      </section>

      <section anchor="eom" title="End of Message Marker">
        <t>Because of variability within I2RS trace log fields,
        implementors MUST use a format-appropriate end of message
        (EOM) indicator in order to signify the end of a particular
        record. That is, regardless of format, the I2RS trace log MUST
        provide a distinct way of distinguishing between the end of
        one record and the beginning of another. For example, in a
        linear formated log (similar to syslog) the EOM marker may be
        a newline character. In an XML formated log, the schema would
        provide for element tags that denote beginning and end of
        records. In a JSON formated log, the syntax would provide
        record separation (likely by comma-separated array
        elements).</t>
      </section>

      <!--      <section anchor="info_optional"
               title="I2RS Trace Log Extensibility and Optional Fields">
        <t/>

        <t>[NOTE: This section is TBD based on further development of
        I2RS WG milestones.]</t>

        <t/>
      </section>-->
    </section>

    <section title="Examples">
      <t>This section shows a sample of what the fields and values could look
        like. <vspace blankLines="1"/></t>

      <figure>
        <artwork><![CDATA[
Event ID:                 1
Starting Timestamp:       2013-09-03T12:00:01.21+00:00
Request State:            COMPLETED
Client ID:                5CEF1870-0326-11E2-A21F-0800200C9A66
Client Priority:          100
Secondary ID:             com.example.RoutingApp
Client Address:           2001:db8:c0c0::2
Requested Operation:      ROUTE_ADD
Applied Operation:        ROUTE_ADD
Operation Data Present:   TRUE
Requested Operation Data: PREFIX 2001:db8:feed:: PREFIX-LEN 64
                          NEXT-HOP 2001:db8:cafe::1
Applied Operation Data:   PREFIX 2001:db8:feed:: PREFIX-LEN 64
                          NEXT-HOP 2001:db8:cafe::1
Transaction ID:           2763461
Result Code:              SUCCESS(0)
Timeout Occurred:         FALSE
Ending Timestamp:         2013-09-03T12:00:01.23+00:00
        ]]></artwork>
      </figure>
    </section>

    <section anchor="operational_guidance"
             title="Operational Guidance">
      <t/>

      <t>Specific operational procedures regarding temporary log
      storage, rollover, retrieval, and access of I2RS trace logs is
      out of scope for this document. Organizations employing I2RS
      trace logging are responsible for establishing proper
      operational procedures that are appropriately suited to their
      specific requirements and operating environment. In this section
      we only provide fundamental and generalized operational
      guidelines that are implementation-independent.</t>

      <t/>

      <section anchor="responsibilities" title="Trace Log Creation">
        <t>The I2RS Agent interacts with the Routing and Signaling
        functions of the Routing Element. Since the I2RS Agent is
        responsible for actually making the routing changes on the
        associated network device, it creates and maintains a log of
        operations that can be retrieved to troubleshoot
	I2RS-related impact to the network.   Changes that occur
	to the network element's local configuration outside of the I2RS
	protocol that preempt I2RS state will only be logged if the
	network element notifies the I2RS Agent.</t>
      </section>

      <section anchor="trace_storage"
               title="Trace Log Temporary Storage">
        <t>The trace information may be temporarily stored either in
        an in-memory buffer or as a file local to the Agent. Care
        should be given to the number of I2RS operations expected on
        a given Agent so that the appropriate storage medium is used
        and to maximize the effectiveness of the log while not
        impacting the performance and health of the Agent.
	Client requests may not always be processed synchronously or within
	a bounded time period.
        Consequently, to ensure that trace log fields, such as "Operation"
        and "Result Code", are part of the same trace log record it may
        require buffering of the trace log entries. This buffering may
        result in additional resource load on the Agent and the network
        element.</t>

        <t><xref
        target="log_rotation"/> discusses rotating the trace log in
        order to preserve the operation history without exhausting
        Agent or network device resources. It is perfectly acceptable,
        therefore, to use both an in-memory buffer for recent
        operations while rotating or archiving older operations to
        a local file.</t>

        <t>It is outside the scope of this document to specify the
        implementation details (i.e., size, throughput, data
        protection, etc.) for the physical storage of the
	I2RS log file.  In terms of data retention,
	attention should be paid the length of time I2RS trace log
	data is kept when that data contains
	security or privacy-sensitive attributes.  The longer this
	data is retained, the higher the impact if it were to be leaked.
	It is also possible that legislation may impose some
	additional requirements on the minimum and/or maximum durations
	for which some kinds of data may be retained.</t>
      </section>

      <section anchor="log_rotation" title="Trace Log Rotation">
        <t>In order to prevent the exhaustion of resources on the I2RS
        Agent or its associated network device, it is RECOMMENDED that
        the I2RS Agent implements trace log rotation. The details on
        how this is achieved are left to the implementation and
        outside the scope of this document. However, it should be
        possible to do file rotation based on either time or size of
        the current trace log. If file rollover is supported, multiple
        archived log files should be supported in order to maximize
        the troubleshooting and accounting benefits of the trace
        log.</t>
      </section>

      <section anchor="log_retrieval" title="Trace Log Retrieval">
        <t>Implementors are free to provide their own, proprietary
        interfaces and develop custom tools to retrieve and display
        the I2RS trace log. These may include the display of the I2RS
        trace log as Command Line Interface (CLI) output. However, a
        key intention of defining this information model is to
        establish a vendor-agnostic and consistent interface to
        collect I2RS trace data. Correspondingly, retrieval of the
        data should also be made vendor-agnostic.</t>

        <t>Despite the fact that export of I2RS trace log
        information could be an invaluable diagnostic tool for
        off-box analysis, exporting this information MUST NOT interfere
        with the ability of the Agent to process new incoming operations.</t>

        <t>The following three sections describe potential ways the
	trace log can be accessed. The use of I2RS Pub-Sub
	for accessing trace log data is mandatory-to-implement, while
        others are optional.</t>

        <section anchor="trace_syslog" title="Retrieval Via Syslog">
          <t>The syslog protocol <xref target="RFC5424"/> is a
          standard way of sending event notification messages from a
          host to a collector. However, the protocol does not define
          any standard format for storing the messages, and thus
          implementors of I2RS tracing would be left to define their
          own format. So, while the data contained within the syslog
          message would adhere to this information model, and may be
          consumable by a human operator, it would not be easily
          parseable by a machine. Syslog MAY be employed as
          a means of retrieving or disseminating the I2RS trace log
          contents.</t>

          <t>If syslog is used for trace log retrieval, then existing
          logging infrastructure and capabilities of syslog
          <xref target="RFC5424"/> should be leveraged without the need
          to define or extend existing formats.
	  That is, the various fields described in
	  <xref target="info_required"/> SHOULD be
          modeled and encoded as Structured Data Elements (referred to
          as "SD-ELEMENT"), as described in Section 6.3.1 of
          <xref target="RFC5424"/>.</t>
        </section>

        <section anchor="i2rs_info_retrieval"
                 title="Retrieval Via I2RS Information Collection">
          <t>Section 6.7 of the I2RS architecture <xref
          target="I-D.ietf-i2rs-architecture"/> defines a mechanism
          for information collection. The information collected
          includes obtaining a snapshot of a large amount of data from
          the network element. It is the intent of I2RS to make this
          data available in an implementor-agnostic fashion.
          Therefore, the I2RS trace log SHOULD be made available via
          the I2RS information collection mechanism either as a single
          snapshot or via a subscription stream.</t>
        </section>

        <section anchor="pub_sub_retrieval"
                 title="Retrieval Via I2RS Pub-Sub">
          <t>Section 7.6 of the I2RS architecture <xref
          target="I-D.ietf-i2rs-architecture"/> goes on to describe
          notification mechanisms for a feed of changes happening
	  within the I2RS layer. Specifically, the requirements for
	  a publish-subscribe system for I2RS are defined in
	  <xref target="I-D.ietf-i2rs-pub-sub-requirements"/>.
	  I2RS Agents MUST support publishing
          I2RS trace log information to that feed as described in that
          document. Subscribers would then receive a live stream of
          I2RS interactions in trace log format and could flexibly
          choose to do a number of things with the log messages. For
          example, the subscribers could log the messages to a
          datastore, aggregate and summarize interactions from a
          single Client, etc. The full range of
          potential activites is virtually limitless and the details
          of how they are performed are outside the scope of this
          document, however.</t>
        </section>
      </section>
    </section>

    <section anchor="IANA" title="IANA Considerations">
      <t>This document makes no request of IANA.</t>
    </section>

    <section anchor="Security" title="Security Considerations">
      <t>The I2RS trace log, like any log file, reveals the state of
      the entity producing it as well as the identifying information
      elements and detailed interactions of the system containing it.
      The information model described in this document does not itself
      introduce any security issues, but it does define the set of
      attributes that make up an I2RS log file. These attributes may
      contain sensitive information and thus should adhere to the
      security, privacy and permission policies of the organization
      making use of the I2RS log file.</t>

      <t>It is outside the scope of this document to specify how to
      protect the stored log file, but it is expected that adequate
      precautions and security best practices such as disk encryption,
      appropriately restrictive file/directory permissions, suitable
      hardening and physical security of logging entities, mutual
      authentication, transport encryption, channel confidentiality,
      and channel integrity if transferring log files. Additionally,
      the potentially sensitive information contained in a log file
      SHOULD be adequately anonymized or obfuscated by operators to
      ensure its privacy.</t>
    </section>

    <section anchor="acknowledgements" title="Acknowledgments">
      <t>The authors would like to thank Alia Atlas for her initial
      feedback and overall support for this work. Additionally, the
      authors acknowledge Alvaro Retana, Russ White, Matt Birkner,
      Jeff Haas, Joel Halpern, Dean Bogdanovich, Ignas Bagdonas, Nobo Akiya,
      Kwang-koog Lee, Sue Hares, Mach Chen, Alex Clemm, Stephen Farrell,
      Benoit Claise, Les Ginsberg, Suresh Krishnan, and Elwyn Davies
      for their reviews,
      contributed text, and suggested improvements to this
      document.</t>
    </section>
  </middle>

  <back>
    <references title="Normative References">
      &I2RS-ARCHITECTURE;

      &I2RS-PUB-SUB-REQ;

      &RFC2119;

      &RFC3339;

      &RFC5424;
    </references>

    <references title="Informative References">
      &I2RS-PROBLEM-STATEMENT;

      &I2RS-RIB-INFO-MODEL;

      &RFC6536;
    </references>
  </back>
</rfc>

PAFTECH AB 2003-20262026-04-23 19:32:26