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SACM Working Group                                           H. Birkholz
Internet-Draft                                            Fraunhofer SIT
Intended status: Informational                          October 14, 2015
Expires: April 16, 2016


     Secure Automation and Continuous Monitoring (SACM) Terminology
                   draft-ietf-sacm-terminology-08

Abstract

   This memo documents terminology used in the documents produced by
   SACM (Security Automation and Continuous Monitoring).

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on April 16, 2016.

Copyright Notice

   Copyright (c) 2015 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
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   described in the Simplified BSD License.






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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terms and Definitions . . . . . . . . . . . . . . . . . . . .   2
   3.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   5.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  10
   6.  Change Log  . . . . . . . . . . . . . . . . . . . . . . . . .  10
   7.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  12
   8.  Informative References  . . . . . . . . . . . . . . . . . . .  14
   Appendix A.  The Attic  . . . . . . . . . . . . . . . . . . . . .  14
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   Our goal with this document is to improve our agreement on the
   terminology used in documents produced by the IETF Working Group for
   Security Automation and Continuous Monitoring.  Agreeing on
   terminology should help reach consensus on which problems we're
   trying to solve, and propose solutions and decide which ones to use.

2.  Terms and Definitions

   This section describes terms that have been defined by other RFC's
   and defines new ones.  The predefined terms will reference the RFC
   and where appropriate will be annotated with the specific context by
   which the term is used in SACM.

   Assertion:  Defined by the ITU in [X.1252] as "a statement made by an
      entity without accompanying evidence of its validity".  In the
      context of SACM, an assertion is a collection result that includes
      metadata about the data source (and optionally a timestamp
      indicating the point in time the assertion was created at).  The
      validity of an assertion cannot be verified.

   Assessment:  Defined in [RFC5209] as "the process of collecting
      posture for a set of capabilities on the endpoint (e.g., host-
      based firewall) such that the appropriate validators may evaluate
      the posture against compliance policy."

      Within SACM the use of the term is expanded to support other uses
      of collected posture (e.g. reporting, network enforcement,
      vulnerability detection, license management).  The phrase "set of
      capabilities on the endpoint" includes: hardware and software
      installed on the endpoint."

   Asset:  Defined in [RFC4949] as "a system resource that is (a)
      required to be protected by an information system's security



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      policy, (b) intended to be protected by a countermeasure, or (c)
      required for a system's mission".  In the scope of SACM, an asset
      can be composed of other assets.  Examples of Assets include:
      Endpoints, Software, Guidance, or X.509 public key certificates.
      An asset is not necessarily owned by an organization.

   Asset Characterization:  Asset characterization is the process of
      defining attributes that describe properties of an identified
      asset.

   Asset Management:  The process by which assets are provisioned,
      updated, maintained and deprecated.

   Attribute:  Defined in [RFC5209] as "data element including any
      requisite meta-data describing an observed, expected, or the
      operational status of an endpoint feature (e.g., anti-virus
      software is currently in use)."  If not indicated otherwise,
      attributes in SACM are represented and processed as attribute
      value pairs, and the terms attribute and endpoint attribute are
      synonyms.

   Authentication:  Defined in [RFC4949] as "the process of verifying a
      claim that a system entity or system resource has a certain
      attribute value."

   Authorization:  Defined in [RFC4949] as "an approval that is granted
      to a system entity to access a system resource."

   Broker:  A broker is a specific controller type that contains control
      plane functions to provide and/or connect services on behalf of
      other SACM components via interfaces on the control plane.  A
      broker may provide, for example, authorization services and find,
      upon request, SACM components providing requested services.

   Building Block:  For SACM, a building block is a unit of
      functionality that is used to compose SACM components.  It
      contains SACM functions and may apply to one or more use cases.
      The functions of a building block can have interfaces on the data
      plane, the control plane, or on the management plane.

   Capability:  The extent of an SACM component's ability enabled by the
      functions (bundled into building blocks) it is composed of.
      Capabilities are propagated by a SACM component and can be
      discovered by or negotiated with other SACM components.  For
      example, the capability of a SACM Provider may be to provide
      endpoint management data, or only a subset of that data.





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   Collection Result:  Information about a target endpoint that is
      produced by a collector conducting a collection task.  A
      collection result is composed of one or more endpoint attributes.

   Collection Task:  The task by which endpoint attributes and/or
      corresponding attribute values about a target endpoint are
      collected.  There are three types of collection tasks, each
      requiring an appropriate set of functions to be included in the
      SACM component conducting the collection task:

      Self-Reported: A SACM component located on the target endpoint
      itself conducts the collection task.

      Remote: A SACM component located on an Endpoint different from the
      target endpoint conducts the collection task via interfaces
      available on the target endpoint, e.g.  SNMP/NETCONF or WMI.

      Observed: A SACM component located on an Endpoint different from
      the target endpoint observes network traffic related to the target
      endpoint and conducts the collection task via interpretation of
      that network traffic.

   Collector:  A piece of software that acquires information about one
      or more target endpoints by conducting collection tasks.  A
      collector provides acquired information to SACM components in the
      form of collection results.  A SACM component that consumes
      collection results may take on the role of a provider and publish
      the collection results in a SACM domain.  (TBD: A collector may
      not be a SACM component and therefore not part of a SACM domain).

   Consumer:  A consumer is a SACM role that is assigned to a SACM
      component that contains functions to receive information from
      other SACM components.

   Control Plane:  An architectural component providing common control
      functions to all SACM components, including authentication,
      authorization, capability discovery or negotiation.  The control
      plane orchestrates the flow on the data plane according to
      guidance and/or input from the management plane.

   Controller:  A controller is a SACM role that is assigned to a SACM
      component containing control plane functions that manage and
      facilitate information sharing or execute on security functions.
      There are three types of SACM controllers: Broker, Proxy, and
      Repository.  Depending on its type, a controller can also contain
      functions that have interfaces on the data plane.





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   Data Confidentiality:  Defined in [RFC4949] as "the property that
      data is not disclosed to system entities unless they have been
      authorized to know the data."

   Data Integrity:  Defined in [RFC4949] as "the property that data has
      not been changed, destroyed, or lost in an unauthorized or
      accidental manner."

   Data Source:  One or more properties that enable a SACM component to
      identify an (target) endpoint that is claimed to be the original
      source of received data.

   Data Origin:  One or more properties that enable a SACM component to
      identify the SACM component that initially acquired or produced
      data about a (target) endpoint (e.g. via collection from a data
      source).

   Data Provenance:  A historical record of the sources, origins and
      evolution of data that is influenced by inputs, entities,
      functions and processes.

   Endpoint:  Defined in [RFC5209] as "any computing device that can be
      connected to a network.  Such devices normally are associated with
      a particular link layer address before joining the network and
      potentially an IP address once on the network.  This includes:
      laptops, desktops, servers, cell phones, or any device that may
      have an IP address."

      To further clarify the [RFC5209] definition, an endpoint is any
      physical or virtual device that may have a network address.  Note
      that, network infrastructure devices (e.g. switches, routers,
      firewalls), which fit the definition, are also considered to be
      endpoints within this document.

      The SACM architecture differentiates two essential categories of
      endpoints: Endpoints whose security posture is intended to be
      assessed (target endpoints) and endpoints that are specifically
      excluded from endpoint posture assessment (excluded endpoints).

      Based on the definition of an asset, an endpoint is a type of
      asset.

   Endpoint Attribute:  In the context of SACM, endpoint attribute is a
      synonym for the term attribute.  Endpoint Attributes are typically
      represented as AVP.

   Evaluation Task:  The task by which endpoint attributes are
      evaluated.



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   Evaluation Result:  The resulting value from having evaluated a set
      of posture attributes.

   Excluded Endpoint:  A specific designation, which is assigned to an
      endpoint that is not supposed to be the subject of a collection
      task (and therefore is not a target endpoint).  Typically but not
      necessarily, endpoints that contain a SACM component (and are
      therefore part of the SACM domain) are designated as excluded
      endpoints.  Target endpoints that contain a SACM component cannot
      be designated as excluded endpoints and are part of the SACM
      domain.

   Expected Endpoint State:  The required state of an endpoint that is
      to be compared against.  This, for example, can be a policy or a
      recorded past state.  A state is represented via a single or an
      associated set of attribute value pairs.

   SACM Function:  A behavioral aspect or capacity of a particular
      building block that is part of a SACM component, which belies that
      SACM component's purpose.  For example, a SACM function with
      interfaces on the control plane can provide a brokering function
      to other SACM components.  Via data plane interfaces, a function
      can act as a provider and/or as a consumer of information.  SACM
      functions can be propagated as the capabilities of a SACM
      component and can be discovered by or negotiated with other SACM
      components.

   Information Model:  An information model is an abstract
      representation of data, their properties, relationships between
      data and the operations that can be performed on the data.  While
      there is some overlap with a data model, [RFC3444] distinguishes
      an information model as being protocol and implementation neutral
      whereas a data model would provide such details.

   Internal Collector:  Internal Collector: a collector that runs on a
      target endpoint to acquire information from that target endpoint.
      (TBD: An internal collector is not a SACM component and therefore
      not part of a SACM domain).

   Management Plane:  An architectural component providing common
      functions to all SACM participants, including [TBD].

   Network Address:  Network addresses are layer specific and follow
      layer specific address schemes.  Each interface of a specific
      layer can be associated with one or more addresses appropriate for
      that layer.  There is no guarantee that an address is globally
      unique.  In general, there is a scope to an address in which it is
      intended to be unique.



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      Examples include: physical Ethernet port with a MAC address, layer
      2 VLAN interface with a MAC address, layer 3 interface with
      multiple IPv6 addresses, layer 3 tunnel ingress or egress with an
      IPv4 address.

   Network Interface:  An endpoint is connected to a network via one or
      more interfaces.  Interfaces can be physical or virtual.
      Interfaces of an endpoint can operate on different layers, most
      prominently what is now commonly called layer 2 and 3.  Within a
      layer, interfaces can be nested.  On layer 2, a root interface is
      typically associated with a physical interface port and nested
      interfaces are virtual interfaces.  In the case of a virtual
      endpoint, a root interface can be a virtual interface.  Virtual
      layer 2 interfaces of one or more endpoints can also constitute an
      aggregated group of links that act as one.  On layer 3, nested
      interfaces typically constitute virtual tunnels or networks.

      Examples include: physical Ethernet port, layer 2 VLAN interface,
      a MC-LAG setup, layer 3 Point-to-Point tunnel ingress or egress.

   Posture:  Defined in [RFC5209] as "configuration and/or status of
      hardware or software on an endpoint as it pertains to an
      organization's security policy."

      This term is used within the scope of SACM to represent the
      configuration and state information that is collected from a
      target endpoint in the form of endpoint attributes (e.g. software/
      hardware inventory, configuration settings, dynamically assigned
      addresses).  This information may constitute one or more posture
      attributes.

   Posture Attributes:  Defined in [RFC5209] as "attributes describing
      the configuration or status (posture) of a feature of the
      endpoint.  A Posture Attribute represents a single property of an
      observed state.  For example, a Posture Attribute might describe
      the version of the operating system installed on the system."

      Within this document this term represents a specific assertion
      about endpoint configuration or state (e.g. configuration setting,
      installed software, hardware) represented via endpoint attributes.
      The phrase "features of the endpoint" highlighted above refers to
      installed software or software components.

   Provider:  A provider is a SACM role that is assigned to a SACM
      component that contains functions to provide information to other
      SACM components.





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   Proxy:  A proxy is a specific controller type that provides data
      plane and control plane functions, information, or services on
      behalf of another component, which is not directly participating
      in the SACM architecture.

   Repository:  A repository is a specific controller type that contains
      functions to store information of a particular kind - typically
      data transported on the data plane, but potentially also data and
      metadata from the control and management plane.  A single
      repository may provide the functions of more than one specific
      repository type (i.e. configuration baseline repository,
      assessment results repository, etc.)

   SACM Role:  SACM roles are associated with SACM components and are
      defined by the set of functions and interfaces a SACM component
      includes.  There are three SACM roles: provider, consumer, and
      controller.  The roles associated with a SACM component are
      determined by the purpose of the functions and corresponding
      interfaces the SACM component is composed of.

   SACM Component:  A composition of building blocks that contain SACM
      functions (acting on control plane, data plane or management
      plane).  SACM defines a set of standard components (e.g. a
      collector, a broker, or a data store).  A SACM component contains
      at least a basic set of control plane building blocks and can
      contain data plane and management plane building blocks.  A SACM
      component residing on an endpoint assigns one or more SACM roles
      to the corresponding endpoint due to the SACM functions it is
      composed of.  A SACM component "resides on" an endpoint and an
      endpoint "contains" a SACM component, correspondingly.  For
      example, a SACM component that is composed solely of building
      blocks that provide information is a provider.

   SACM Component Discovery:  The function by which a SACM component
      (e.g. by role, capabilities, or data provided/consumed) can be
      discovered.

   SACM Domain:  Endpoints that include a SACM component compose a SACM
      domain.  (To be revised, additional definition content TBD,
      possible dependencies to SACM architecture)

   Security Automation:  The process of which security alerts can be
      automated through the use of different tools to monitor, evaluate
      and analyze endpoint and network traffic for the purposes of
      detecting misconfigurations, misbehaviors or threats.

   Statement:  The output of a provider, e.g. a report or an assertion
      acquired via a collection result from a collector, that includes



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      metadata about the data origin and the point in time the statement
      was created at.  A statement can be accompanied by evidence of the
      validity of its metadata.

   Supplicant:  The entity seeking to be authenticated by the Management
      Plane for the purpose of participating in the SACM architecture.

   System Resource:  Defined in [RFC4949] as "data contained in an
      information system; or a service provided by a system; or a system
      capacity, such as processing power or communication bandwidth; or
      an item of system equipment (i.e., hardware, firmware, software,
      or documentation); or a facility that houses system operations and
      equipment.

   Target Endpoint:  A target endpoint is an "endpoint under assessment"
      (even if it is not actively under assessment at all times) or
      "endpoint of interest".  Every endpoint that is not specifically
      designated as an excluded endpoint is a target endpoint.  A target
      endpoint is not part of a SACM domain unless it contains a SACM
      component (e.g. a SACM component that publishes collection results
      coming from an internal collector).

      A target endpoint is similar to a device that is a Target of
      Evaluation (TOE) as defined in Common Criteria.

   Target Endpoint Discovery:  The function by which target endpoints
      can be discovered.  The output of target endpoint discovery
      typically includes identifying endpoint attributes.

   Target Endpoint Identifier:  The target endpoint discovery process
      and collection tasks targeted at target endpoints can result in a
      set of identifying endpoint attributes.  This set of identifying
      endpoint attributes is used as a target endpoint identifier
      referring to a specific target endpoint.  Depending on the
      available identifying attributes this reference can be ambiguous
      and is a "best-effort" mechanism.  Every distinct set of
      identifying endpoint attributes can be associated with a unique
      target endpoint label.

   Target Endpoint Label:  An artificially created id that references a
      distinct set of identifying attributes (Target Endpoint
      Identifier).  A target endpoint label is unique in a SACM domain
      and created by a SACM component that contains an appropriate
      building block of functions.

   Timestamps :  Defined in [RFC4949] as "with respect to a data object,
      a label or marking in which is recorded the time (time of day or
      other instant of elapsed time) at which the label or marking was



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      affixed to the data object" and as "with respect to a recorded
      network event, a data field in which is recorded the time (time of
      day or other instant of elapsed time) at which the event took
      place.".

      This term is used in SACM to describe a recorded point in time at
      which an endpoint attribute is created or updated by a target
      endpoint and observed, transmitted or processed by a SACM
      component.  Timestamps can be created by target endpoints or SACM
      components and are associated with endpoint attributes provided or
      consumed by SACM components.  Outside of the domain of SACM
      components the assurance of correctness of time stamps is
      typically significantly lower than inside a SACM domain.  In
      general, it cannot be simply assumed that the source of time a
      target endpoint uses is synchronized or trustworthy.

3.  IANA Considerations

   This memo includes no request to IANA.

4.  Security Considerations

   This memo documents terminology for security automation.  While it is
   about security, it does not affect security.

5.  Acknowledgements

6.  Change Log

   Changes from version 00 to version 01:

   o  Added simple list of terms extracted from UC draft -05.  It is
      expected that comments will be received on this list of terms as
      to whether they should be kept in this document.  Those that are
      kept will be appropriately defined or cited.

   Changes from version 01 to version 02:

   o  Added Vulnerability, Vulnerability Management, xposure,
      Misconfiguration, and Software flaw.

   Changes from version 02 to version 03:

   o  Removed Section 2.1.  Cleaned up some editing nits; broke terms
      into 2 sections (predefined and newly defined terms).  Added some
      of the relevant terms per the proposed list discussed in the IETF
      89 meeting.




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   Changes from version 03 to version 04:

   o  TODO

   Changes from version 04 to version 05:

   o  TODO

   Changes from version 05 to version 06:

   o  Updated author information.

   o  Combined "Pre-defined Terms" with "New Terms and Definitions".

   o  Removed "Requirements language".

   o  Removed unused reference to use case draft; resulted in removal of
      normative references.

   o  Removed introductory text from Section 1 indicating that this
      document is intended to be temporary.

   o  Added placeholders for missing change log entries.

   Changes from version 06 to version 07:

   o  Added Contributors section.

   o  Updated author list.

   o  Changed title from "Terminology for Security Assessment" to
      "Secure Automation and Continuous Monitoring (SACM) Terminology".

   o  Changed abbrev from "SACM-Terms" to "SACM Terminology".

   o  Added appendix The Attic to stash terms for future updates.

   o  Added Authentication, Authorization, Data Confidentiality, Data
      Integrity, Data Origin, Data Provenance, SACM Component, SACM
      Component Discovery, Target Endpoint Discovery.

   o  Major updates to Building Block, Function, SACM Role, Target
      Endpoint.

   o  Minor updates to Broker, Capability, Collection Task, Evaluation
      Task, Posture.





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   o  Relabled Role to SACM Role, Endpoint Target to Target Endpoint,
      Endpoint Discovery to Endpoint Identification.

   o  Moved Asset Targeting, Client, Endpoint Identification to The
      Attic.

   o  Endpoint Attributes added as a TODO.

   o  Changed the structure of the Change Log.

   Changes from version 07 to version 08:

   o  Added Assertion, Collection Result, Collector, Excluded Endpoint,
      Internal Collector, Network Address, Network Interface, SACM
      Domain, Statement, Target Endpoint Identifier, Target Endpoint
      Label, Timestamp.

   o  Major updates to Attributes, Broker, Collection Task, Consumer,
      Controller, Control Plane, Endpoint Attributes, Expected Endpoint
      State, SACM Function, Provider, Proxy, Repository, SACM Role,
      Target Endpoint.

   o  Minor updates to Asset, Building Block, Data Origin, Data Source,
      Data Provenance, Endpoint, Management Plane, Posture, Posture
      Attribute, SACM Component, SACM Component Discovery, Target
      Endpoint Discovery.

   o  Relabled Function to SACM Function.

7.  Contributors

   David Waltermire
   National Institute of Standards and Technology
   100 Bureau Drive
   Gaithersburg, MD  20877
   USA

   Email: david.waltermire@nist.gov


   Adam W. Montville
   Center for Internet Security
   31 Tech Valley Drive
   East Greenbush, NY  12061
   USA

   Email: adam.w.montville@gmail.com




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   David Harrington
   Effective Software
   50 Harding Rd
   Portsmouth, NH  03801
   USA

   Email: ietfdbh@comcast.net


   Nancy Cam-Winget
   Cisco Systems
   3550 Cisco Way
   San Jose, CA  95134
   USA

   Email: ncamwing@cisco.com


   Jarrett Lu
   Oracle Corporation
   4180 Network Circle
   Santa Clara, CA  95054
   USA

   Email: jarrett.lu@oracle.com


   Brian Ford
   Lancope
   3650 Brookside Parkway, Suite 500
   Alpharetta, GA  30022
   USA

   Email: bford@lancope.com


   Merike Kaeo
   Double Shot Security
   3518 Fremont Avenue North, Suite 363
   Seattle, WA  98103
   USA

   Email: merike@doubleshotsecurity.com








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8.  Informative References

   [RFC3444]  Pras, A. and J. Schoenwaelder, "On the Difference between
              Information Models and Data Models", RFC 3444, DOI
              10.17487/RFC3444, January 2003,
              <http://www.rfc-editor.org/info/rfc3444>.

   [RFC4949]  Shirey, R., "Internet Security Glossary, Version 2", FYI
              36, RFC 4949, DOI 10.17487/RFC4949, August 2007,
              <http://www.rfc-editor.org/info/rfc4949>.

   [RFC5209]  Sangster, P., Khosravi, H., Mani, M., Narayan, K., and J.
              Tardo, "Network Endpoint Assessment (NEA): Overview and
              Requirements", RFC 5209, DOI 10.17487/RFC5209, June 2008,
              <http://www.rfc-editor.org/info/rfc5209>.

   [X.1252]   "ITU-T X.1252 (04/2010)", n.d..

Appendix A.  The Attic

   The following terms are stashed for now and will be updated later:

   Asset Targeting:  Asset targeting is the use of asset identification
      and categorization information to drive human-directed, automated
      decision making for data collection and analysis in support of
      endpoint posture assessment.

   Client:  An architectural component receiving services from another
      architectural component.

   Endpoint Identification (TBD per list; was "Endpoint Discovery"):
      The process by which an endpoint can be identified.

Author's Address

   Henk Birkholz
   Fraunhofer SIT
   Rheinstrasse 75
   Darmstadt  64295
   Germany

   Email: henk.birkholz@sit.fraunhofer.de









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