Network Working Group                                      A. Westerinen
Request for Comments: 3198                                 J. Schnizlein
Category: Informational                                    Cisco Systems
                                                           J. Strassner
                                                 Intelliden Corporation
                                                           M. Scherling
                                                                  xCert
                                                               B. Quinn
                                                         Celox Networks
                                                              S. Herzog
                                                       PolicyConsulting
                                                               A. Huynh
                                                    Lucent Technologies
                                                             M. Carlson
                                                       Sun Microsystems
                                                               J. Perry
                                                      Network Appliance
                                                          S. Waldbusser
                                                          November 2001


               Terminology for Policy-Based Management

Status of this Memo

  This memo provides information for the Internet community.  It does
  not specify an Internet standard of any kind.  Distribution of this
  memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2001).  All Rights Reserved.

Abstract

  This document is a glossary of policy-related terms.  It provides
  abbreviations, explanations, and recommendations for use of these
  terms.  The document takes the approach and format of RFC 2828, which
  defines an Internet Security Glossary. The intent is to improve the
  comprehensibility and consistency of writing that deals with network
  policy, particularly Internet Standards documents (ISDs).










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Table of Contents

  1. Introduction...................................................  2
  2. Explanation of Paragraph Markings..............................  3
  3. Terms..........................................................  3
  4. Intellectual Property.......................................... 16
  5. Acknowledgements............................................... 17
  6. Security Considerations........................................ 17
  7. References..................................................... 17
  8. Authors' Addresses............................................. 19
  9. Full Copyright Statement....................................... 21

1. Introduction

  This document provides abbreviations, definitions, and explanations
  of terms related to network policy.  All definitions are provided in
  Section 3, with the terms listed in alphabetical order.

  The intent is to improve the comprehensibility and consistency of
  Internet Standards documents (ISDs) -- i.e., RFCs, Internet-Drafts,
  and other material produced as part of the Internet Standards Process
  [RFC2026].  Benefits across the ISDs are well-stated in the
  Introduction to RFC 2828 [RFC2828]:

  o  "Clear, Concise, and Easily Understood Documentation" - Requires
     that the set of terms and definitions be consistent, self-
     supporting and uniform across all ISDs.

  o  Technical Excellence - Where all ISDs use terminology accurately,
     precisely, and unambiguously.

  o  Prior Implementation and Testing - Requires that terms are used in
     their plainest form, that private and "made-up" terms are avoided
     in ISDs, and that new definitions are not created that conflict
     with established ones.

  o  "Openness, Fairness, and Timeliness" - Where ISDs avoid terms that
     are proprietary or otherwise favor a particular vendor, or that
     create a bias toward a particular technology or mechanism.

  Common and/or controversial policy terms are defined.  These terms
  are directly related and specific to network policy.

  Wherever possible, this document takes definitions from existing
  ISDs.  It should be noted that:

  o  Expired Internet-Drafts are not referenced, nor are their
     terminology and definitions used in this document.



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  o  Multiple definitions may exist across the ISDs.  Each definition
     is listed, with its source.

2. Explanation of Paragraph Markings

  Section 3 marks terms and definitions as follows:

  o  Capitalization: Only terms that are proper nouns are capitalized.

  o  Paragraph Marking: Definitions and explanations are stated in
     paragraphs that are marked as follows:

     -  "P" identifies basic policy-related terms.

     -  "T" identifies various techniques to create or convey policy-
        related information in a network.  For example, COPS and an
        "Information Model" are two techniques for communicating and
        describing policy-related data.  SNMP and MIBs are another.

     -  "A" identifies specific Work Groups and general "areas of use"
        of policy.  For example, AAA and QoS are two "areas of use"
        where policy concepts are extremely important to their function
        and operation.

3. Terms

  Note:  In providing policy definitions, other "technology specific"
  terms (for example, related to Differentiated Services) may be used
  and referenced.  These non-policy terms will not be defined in this
  document, and the reader is requested to go to the referenced ISD for
  additional detail.

  $ AAA
     See "Authentication, Authorization, Accounting".

  $ abstraction levels
     See "policy abstraction".

  $ action
     See "policy action".

  $ Authentication, Authorization, Accounting (AAA)
     (A) AAA deals with control, authentication, authorization and
         accounting of systems and environments based on policies set
         by the administrators and users of the systems.  The use of
         policy may be implicit - as defined by RADIUS [RFC2138]. In
         RADIUS, a network access server sends dial-user credentials to
         an AAA server, and receives authentication that the user is



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         who he/she claims, along with a set of attribute-value pairs
         authorizing various service features. Policy is implied in
         both the authentication, which can be restricted by time of
         day, number of sessions, calling number, etc., and the
         attribute-values authorized.

  $ CIM
     See "Common Information Model".

  $ Common Information Model (CIM)
     (T) An object-oriented information model published by the DMTF
         (Distributed Management Task Force) [DMTF].  It consists of a
         Specification detailing the abstract modeling constructs and
         principles of the Information Model, and a textual language
         definition to represent the Model.  CIM's schemas are defined
         as a set of files, written in the language of the
         Specification, with graphical renderings using UML [UML].
         Sets of classes and associations represent CIM's Core and
         Common Models, defining an information model for the
         "enterprise" - addressing general concepts (in Core), and
         systems, devices, users, software distribution, the physical
         environment, networks and policy (in the Common Models).  (See
         also "information model".)

  $ Common Open Policy Service (COPS)
     (T) A simple query and response TCP-based protocol that can be
         used to exchange policy information between a Policy Decision
         Point (PDP) and its clients (Policy Enforcement Points, PEPs)
         [RFC2748].  The COPS protocol is used to provide for the
         outsourcing of policy decisions for RSVP [RFC2749]. Another
         usage is for the provisioning of policy [RFC3084]. (See also
         "Policy Decision Point" and "Policy Enforcement Point".)

  $ condition
     See "policy condition".

  $ configuration
     (P) "Configuration" can be defined from two perspectives:
         -  The set of parameters in network elements and other systems
            that determine their function and operation. Some
            parameters are static, such as packet queue assignment and
            can be predefined and downloaded to a network element.
            Others are more dynamic, such as the actions taken by a
            network device upon the occurrence of some event.  The
            distinction between static (predefined) "configuration" and
            the dynamic state of network elements blurs as setting
            parameters becomes more responsive, and signaling controls
            greater degrees of a network device's behavior.



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         -  A static setup of a network element, done before shipment
            to a customer and which cannot be modified by the customer.
         The first is the accepted usage in the Internet community.

  $ COPS
     See "Common Open Policy Service".

  $ data model
     (T) A mapping of the contents of an information model into a form
         that is specific to a particular type of data store or
         repository.  A "data model" is basically the rendering of an
         information model according to a specific set of mechanisms
         for representing, organizing, storing and handling data.  It
         has three parts [DecSupp]:
         -  A collection of data structures such as lists, tables,
            relations, etc.
         -  A collection of operations that can be applied to the
            structures such as retrieval, update, summation, etc.
         -  A collection of integrity rules that define the legal
            states (set of values) or changes of state (operations on
            values).
         (See also "information model".)

  $ DEN
     See "Directory Enabled Networks".

  $ Differentiated Services (DS)
     (T) The IP header field, called the DS-field.  In IPv4, it defines
         the layout of the ToS (Type of Service) octet; in IPv6, it is
         the Traffic Class octet [RFC2474].
     (A) "Differentiated Services" is also an "area of use" for QoS
         policies.  It requires policy to define the correspondence
         between codepoints in the packet's DS-field and individual
         per-hop behaviors (to achieve a specified per-domain
         behavior).  In addition, policy can be used to specify the
         routing of packets based on various classification criteria.
         (See also "Quality of Service" and "filter".)

  $ diffserv
     See "Differentiated Services".

  $ Directory Enabled Networks (DEN)
     (T) A data model that is the LDAP mapping of CIM (the Common
         Information Model).  Its goals are to enable the deployment
         and use of policy by starting with common service and user
         concepts (defined in the information model), specifying their





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         mapping/storage in an LDAP-based repository, and using these
         concepts in vendor/device-independent policy rules [DMTF].
         (See also "Common Information Model" and "data model".)

  $ domain
     (P) A collection of elements and services, administered in a
         coordinated fashion.  (See also "policy domain".)

  $ DS
     See "Differentiated Services".

  $ filter
     (T) A set of terms and/or criteria used for the purpose of
         separating or categorizing.  This is accomplished via single-
         or multi-field matching of traffic header and/or payload data.
         "Filters" are often manipulated and used in network operation
         and policy.  For example, packet filters specify the criteria
         for matching a pattern (for example, IP or 802 criteria) to
         distinguish separable classes of traffic.

  $ goal
     See "policy goal".

  $ information model
     (T) An abstraction and representation of the entities in a managed
         environment, their properties, attributes and operations, and
         the way that they relate to each other.  It is independent of
         any specific repository, software usage, protocol, or
         platform.

  $ Management Information Base (MIB)
     (T) A collection of information that can be accessed via the
         Simple Network Management Protocol.  Management information is
         defined in MIB modules using the rules contained in SNMP's
         Structure of Management Information (SMI) specifications
         [RFC2570].  Management information is an abstract concept, and
         definitions can be created for high level policy
         specifications, low level policy, as well as technology and
         vendor specific configurations, status and statistics.  (See
         also "Simple Network Management Protocol" and "Structure of
         Management Information".)

  $ MIB
     See "Management Information Base".







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  $ MPLS
     See "Multiprotocol Label Switching".  (Also, MPLS may refer to
     Multi-Protocol Lambda Switching in optical networks.  But, this is
     unrelated to policy and not discussed further in this document.)

  $ Multiprotocol Label Switching (MPLS)
     (T) Integrates a label swapping and switching framework with
         network layer routing [RFC2702].  The basic idea involves
         assigning short fixed length labels to packets at the ingress
         to an MPLS cloud.  Throughout the interior of the MPLS domain,
         the labels attached to packets are used to make forwarding
         decisions (usually without recourse to the original packet
         headers).

  $ outsourced policy
     (P) An execution model where a policy enforcement device issues a
         query to delegate a decision for a specific policy event to
         another component, external to it.  For example, in RSVP, the
         arrival of a new RSVP message to a PEP requires a fast policy
         decision (not to delay the end-to-end setup). The PEP may use
         COPS-RSVP to send a query to the PDP, asking for a policy
         decision [RFC2205, RFC2748].  "Outsourced policy" is
         contrasted with "provisioned policy", but they are not
         mutually exclusive and operational systems may combine the
         two.

  $ PCIM
     See "Policy Core Information Model".

  $ PDP
     See "Policy Decision Point".

  $ PEP
     See "Policy Enforcement Point".

  $ PIB
     See "Policy Information Base".

  $ policy
     (P) "Policy" can be defined from two perspectives:
         -  A definite goal, course or method of action to guide and
            determine present and future decisions.  "Policies" are
            implemented or executed within a particular context (such
            as policies defined within a business unit).
         -  Policies as a set of rules to administer, manage, and
            control access to network resources [RFC3060].





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         Note that these two views are not contradictory since
         individual rules may be defined in support of business goals.
         (See also "policy goal", "policy abstraction" and "policy
         rule".)

  $ policy abstraction
     (P) Policy can be represented at different levels, ranging from
         business goals to device-specific configuration parameters.
         Translation between different levels of "abstraction" may
         require information other than policy, such as network and
         host parameter configuration and capabilities.  Various
         documents and implementations may specify explicit levels of
         abstraction.  However, these do not necessarily correspond to
         distinct processing entities or the complete set of levels in
         all environments.  (See also "configuration" and "policy
         translation".)

  $ policy action
     (P) Definition of what is to be done to enforce a policy rule,
         when the conditions of the rule are met.  Policy actions may
         result in the execution of one or more operations to affect
         and/or configure network traffic and network resources.
         -  In [RFC3060], a rule's actions may be ordered.

  $ policy condition
     (P) A representation of the necessary state and/or prerequisites
         that define whether a policy rule's actions should be
         performed.  This representation need not be completely
         specified, but may be implicitly provided in an implementation
         or protocol.  When the policy condition(s) associated with a
         policy rule evaluate to TRUE, then (subject to other
         considerations such as rule priorities and decision
         strategies) the rule should be enforced.
     (T) In [RFC3060], a rule's conditions can be expressed as either
         an ORed set of ANDed sets of statements (disjunctive normal
         form), or an ANDed set of ORed sets of statements (conjunctive
         normal form).  Individual condition statements can also be
         negated.

  $ policy conflict
     (P) Occurs when the actions of two rules (that are both satisfied
         simultaneously) contradict each other.  The entity
         implementing the policy would not be able to determine which
         action to perform.  The implementers of policy systems must
         provide conflict detection and avoidance or resolution
         mechanisms to prevent this situation.  "Policy conflict" is
         contrasted with "policy error".




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  $ policy conversion
     See "policy translation".

  $ Policy Core Information Model (PCIM) [RFC3060]
     (T) An information model describing the basic concepts of policy
         groups, rules, conditions, actions, repositories and their
         relationships.  This model is described as a "core" model
         since it cannot be applied without domain-specific extensions
         (for example, extensions for QoS or IPsec).  PCIM is "core"
         with respect to the area of policy.  However, it is a "Common
         Model," with respect to CIM - in that it extends the basic CIM
         concepts for policy.  (See also "Common Information Model".)

  $ policy decision
     (P) Two perspectives of "policy decision" exist:
         -  A "process" perspective that deals with the evaluation of a
            policy rule's conditions
         -  A "result" perspective that deals with the actions for
            enforcement, when the conditions of a policy rule are TRUE

  $ Policy Decision Point (PDP)
     (P) A logical entity that makes policy decisions for itself or for
         other network elements that request such decisions [RFC2753].
         (See also "policy decision".)

  $ policy domain
     (P) A collection of elements and services, and/or a portion of an
         Internet over which a common and consistent set of policies
         are administered in a coordinated fashion [RFC2474]. This
         definition of a policy domain does not preclude multiple
         sources of policy creation within an organization, but does
         require that the resultant policies be coordinated.
         -  Policies defined in the context of one domain may need to
            be communicated or negotiated outside of that domain. (See
            also "policy negotiation".)

  $ policy enforcement
     (P) The execution of a policy decision.

  $ Policy Enforcement Point (PEP)
     (P) A logical entity that enforces policy decisions [RFC2753].
         (See also "policy enforcement".)

  $ policy error
     (P) "Policy errors" occur when attempts to enforce policy actions
         fail, whether due to temporary state or permanent mismatch
         between the policy actions and the device enforcement
         capabilities.  This is contrasted with "policy conflict".



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  $ policy goal
     (P) Goals are the business objectives or desired state intended to
         be maintained by a policy system.  As the highest level of
         abstraction of policy, these goals are most directly described
         in business rather than technical terms.  For example, a goal
         might state that a particular application operate on a network
         as though it had its own dedicated network, despite using a
         shared infrastructure. 'Policy goals' can include the
         objectives of a service level agreement, as well as the
         assignment of resources to applications or individuals.  A
         policy system may be created that automatically strives to
         achieve a goal through feedback regarding whether the goal
         (such as a service level) is being met.

  $ Policy Information Base (PIB)
     (T) Collections of related PRovisioning Classes (PRCs), defined as
         a module.  (See also "PRovisioning Class".)

  $ policy mapping
     See "policy translation".

  $ policy negotiation
     (P) Exposing the desired or appropriate part of a policy to
         another domain.  This is necessary to support partial
         interconnection between domains, which are operating with
         different sets of policies.

  $ policy repository
     (P) "Policy repository" can be defined from three perspectives:
         -  A specific data store that holds policy rules, their
            conditions and actions, and related policy data.  A
            database or directory would be an example of such a store.
         -  A logical container representing the administrative scope
            and naming of policy rules, their conditions and actions,
            and related policy data.  A "QoS policy" domain would be an
            example of such a container.
         -  In [RFC3060], a more restrictive definition than the prior
            one exists.  A PolicyRepository is a model abstraction
            representing an administratively defined, logical container
            for reusable policy elements.

  $ policy request
     (P) A message requesting a policy-related service.  This may refer
         to a request to retrieve a specific set of policy rules, to
         determine the actions to enforce, or other policy requests.
         When sent by a PEP to a PDP, it is more accurately qualified
         as a "policy decision request" [RFC2753].  (See also "policy
         decision".)



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  $ policy rule
     (P) A basic building block of a policy-based system.  It is the
         binding of a set of actions to a set of conditions - where the
         conditions are evaluated to determine whether the actions are
         performed [RFC3060].

  $ policy server
     (P) A marketing term whose definition is imprecise. Originally,
         [RFC2753] referenced a "policy server".  As the RFC evolved,
         this term became more precise and known as the Policy Decision
         Point (PDP).  Today, the term is used in marketing and other
         literature to refer specifically to a PDP, or for any entity
         that uses/services policy.

  $ policy translation
     (P) The transformation of a policy from a representation and/or
         level of abstraction, to another representation or level of
         abstraction.  For example, it may be necessary to convert PIB
         data to a command line format.  In this "conversion," the
         translation to the new representation is likely to require a
         change in the level of abstraction (becoming more or less
         specific).  Although these are logically distinct tasks, they
         are (in most cases) blurred in the act of
         translating/converting/mapping.  Therefore, this is also known
         as "policy conversion" or "policy mapping".

  $ PolicyGroup
     (T) An abstraction in the Policy Core Information Model [RFC3060].
         It is a class representing a container, aggregating either
         policy rules or other policy groups.  It allows the grouping
         of rules into a Policy, and the refinement of high-level
         Policies to lower-level or different (i.e., converted or
         translated) peer groups.

  $ PRC
     See "PRovisioning Class".

  $ PRI
     See "PRovisioning Instance".

  $ provisioned policy
     (P) An execution model where network elements are pre-configured,
         based on policy, prior to processing events. Configuration is
         pushed to the network device, e.g., based on time of day or at
         initial booting of the device.  The focus of this model is on
         the distribution of configuration information, and is
         exemplified by Differentiated Services [RFC2475].  Based on
         events received, devices use downloaded (pre-provisioned)



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         mechanisms to implement policy. "Provisioned policy" is
         contrasted with "outsourced policy".

  $ PRovisioning Class (PRC)
     (T) An ordered set of attributes representing a type of policy
         data.  PRCs are defined in PIB modules (encoded using SPPI)
         and registered in the Object Identifier tree.  Instances of
         each PRC are organized in tables, similar to conceptual tables
         in SMIv2.  (See also "Structure of Policy Provisioning
         Information" and "Policy Information Base".)
         The acronym, PRC, has evolved from "policy rule class" to
         "provisioning class".  The reason for the change is that a
         discrepancy existed between the use of the words, "policy
         rule" in the PRC context versus other uses in PCIM and the
         industry.  In the latter, rules are If/Then statements - a
         binding of conditions to actions.  PRCs are not "rules" by
         this definition, but the encoding of (network-wide)
         configuration information for a device.

  $ PRovisioning Instance (PRI)
     (T) An instantiation of a PRovisioning Class.  (See also
         "PRovisioning Class".)

  $ QoS
     See "Quality of Service".

  $ Quality of Service (QoS)
     (A) At a high level of abstraction, "Quality of Service" refers to
         the ability to deliver network services according to the
         parameters specified in a Service Level Agreement. "Quality"
         is characterized by service availability, delay, jitter,
         throughput and packet loss ratio.  At a network resource
         level, "Quality of Service" refers to a set of capabilities
         that allow a service provider to prioritize traffic, control
         bandwidth, and network latency.  There are two different
         approaches to "Quality of Service" on IP networks: Integrated
         Services [RFC1633], and Differentiated Service [RFC2475].
         Integrated Services require policy control over the creation
         of signaled reservations, which provide specific quantitative
         end-to-end behavior for a (set of) flow(s).  In contrast,
         Differentiated Services require policy to define the
         correspondence between codepoints in the packet's DS-field and
         individual per-hop behaviors (to achieve a specified per-
         domain behavior).  A maximum of 64 per-hop behaviors limit the
         number of classes of service traffic that can be marked at any
         point in a domain.  These classes of service signal the
         treatment of the packets with respect to various QoS aspects,
         such as flow priority and packet drop precedence.  In



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         addition, policy can be used to specify the routing of packets
         based on various classification criteria.  Policy controls the
         set of configuration parameters and routing for each class in
         Differentiated Service, and the admission conditions for
         reservations in Integrated Services.  (See also "policy
         abstraction" and "Service Level Agreement".)

  $ Resource reSerVation Protocol (RSVP)
     (T) A setup protocol designed for an Integrated Services Internet,
         to reserve network resources for a path [RFC2205]. And, a
         signaling mechanism for managing application traffic's QoS in
         a Differentiated Service network.

  $ role
     (P) "Role" is defined from three perspectives:
         -  A business position or function, to which people and
            logical entities are assigned [X.500]
         -  The labeled endpoints of a UML (Unified Modeling Language)
            association.  Quoting from [UML], "When a class
            participates in an association, it has a specific role that
            it plays in that relationship; a role is just the face the
            class at the near end of the association presents to the
            class at the other end of the association".  The Policy
            Core Information Model [RFC3060] uses UML to depict its
            class hierarchy. Relationships/associations are significant
            in the model.
         -  An administratively specified characteristic of a managed
            element (for example, an interface).  It is a selector for
            policy rules and PRovisioning Classes (PRCs), to determine
            the applicability of the rule/PRC to a particular managed
            element [RFC3060].
         Only the third definition (roles as selectors of policy) is
         directly related to the management of network policy. However,
         the first definition (roles as business positions and
         functions) may be referenced in policy conditions and actions.

  $ role combination
     (P) A lexicographically ordered set of roles that characterize
         managed elements and indicate the applicability of policy
         rules and PRovisioning Classes (PRCs).  A policy system uses
         the set of roles reported by the managed element to determine
         the correct rules/PRCs to be sent for enforcement.  That
         determination may examine all applicable policy rules
         identified by the role combination, its sub-combinations and
         the individual roles in the combination [RFC3060].  In the
         case of PRCs, a PRC must explicitly match the role combination
         of the managed element in order to be applicable and/or
         enforced.  (The comparison is typically case-sensitive.)  The



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         final set of rules/PRCs for enforcement are defined by the
         policy system, as appropriate for the specified role
         combination of the managed element.

  $ RSVP
     See "Resource reSerVation Protocol".

  $ rule
     See "policy rule".

  $ rule based engine
     (T) A rule based engine is able to evaluate policy condition(s)
         and trigger appropriate policy actions.  A particular rule
         based engine may only be capable of acting upon policy rules
         that are formatted in a specified way or adhere to a specific
         language.

  $ schema
     (T) Two different perspectives of schema are defined:
         -  A set of rules that determines what data can be stored in a
            database or directory service [DirServs]
         -  A collection of data models that are each bound to the same
            type of repository.
         The latter is the preferred and recommended one for Internet
         Standards documents.  (See also "data model".)

  $ service
     (P) The behavior or functionality provided by a network, network
         element or host [DMTF, RFC2216].  Quoting from RFC 2216
         [RFC2216], in order to completely specify a "service", one
         must define the "functions to be performed ..., the
         information required ... to perform these functions, and the
         information made available by the element to other elements of
         the system".  Policy can be used to configure a "service" in a
         network or on a network element/host, invoke its
         functionality, and/or coordinate services in an interdomain or
         end-to-end environment.

  $ Service Level Agreement (SLA)
     (P) The documented result of a negotiation between a
         customer/consumer and a provider of a service, that specifies
         the levels of availability, serviceability, performance,
         operation or other attributes of the service [RFC2475]. (See
         also "Service Level Objective".)







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  $ Service Level Objective (SLO)
     (P) Partitions an SLA into individual metrics and operational
         information to enforce and/or monitor the SLA.  "Service Level
         Objectives" may be defined as part of an SLA, an SLS, or in a
         separate document.  It is a set of parameters and their
         values.  The actions of enforcing and reporting monitored
         compliance can be implemented as one or more policies.  (See
         also "Service Level Agreement".)

  $ Service Level Specification (SLS)
     (P) Specifies handling of customer's traffic by a network
         provider.  It is negotiated between a customer and the
         provider, and (for example) in a DiffServ environment, defines
         parameters such as specific Code Points and the Per-Hop-
         Behavior, profile characteristics and treatment of the traffic
         for those Code Points.  An SLS is a specific SLA (a negotiated
         agreement) and its SLOs (the individual metrics and
         operational data to enforce) to guarantee quality of service
         for network traffic.  (See also "Service Level Agreement" and
         "Service Level Objective".)

  $ Simple Network Management Protocol (SNMP)
     (T) SNMP is a framework (including a protocol) for managing
         systems in a network environment [RFC2570].  It can be used
         for policy-based configuration and control using a specific
         MIB Module designed to execute policies on managed elements
         via scripts.  The elements (instances) in a network device are
         evaluated using a policy filter, to determine where policy
         will be applied.

  $ SLA
     See "Service Level Agreement".

  $ SLO
     See "Service Level Objective".

  $ SLS
     See "Service Level Specification".

  $ SMIv2
     See "Structure of Management Information".

  $ SNMP
     See "Simple Network Management Protocol".

  $ SPPI
     See "Structure of Policy Provisioning Information".




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  $ Structure of Policy Provisioning Information (SPPI)
     (T) An adapted subset of SNMP's Structure of Management
         Information (SMIv2) that is used to encode collections of
         related PRovisioning Classes as a PIB [RFC3159]. (See also
         "Policy Information Base" and "PRovisioning Class".)

  $ Structure of Management Information, version 2 (SMIv2)
     (T) An adapted subset of OSI's Abstract Syntax Notation One, ASN.1
         (1988) used to encode collections of related objects as SNMP
         Management Information Base (MIB) modules [RFC2578].

  $ subject
     (P) An entity, or collection of entities, which originates a
         request, and is verified as authorized/not authorized to
         perform that request.

  $ target
     (P) An entity, or collection of entities, which is affected by a
         policy.  For example, the "targets" of a policy to reconfigure
         a network device are the individual services that are updated
         and configured.

4. Intellectual Property

  The IETF takes no position regarding the validity or scope of any
  intellectual property or other rights that might be claimed to
  pertain to the implementation or use of the technology described in
  this document or the extent to which any license under such rights
  might or might not be available; neither does it represent that it
  has made any effort to identify any such rights.  Information on the
  IETF's procedures with respect to rights in standards-track and
  standards-related documentation can be found in BCP-11.

  Copies of claims of rights made available for publication and any
  assurances of licenses to be made available, or the result of an
  attempt made to obtain a general license or permission for the use of
  such proprietary rights by implementers or users of this
  specification can be obtained from the IETF Secretariat.

  The IETF invites any interested party to bring to its attention any
  copyrights, patents or patent applications, or other proprietary
  rights which may cover technology that may be required to practice
  this standard.  Please address the information to the IETF Executive
  Director.







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5. Acknowledgements

  This document builds on the work of previous terminology drafts. The
  authors of these documents were Fran Reichmeyer, Dan Grossman, John
  Strassner, Ed Ellesson and Matthew Condell.  Also, definitions for
  the general concepts of policy and policy rule include input from
  Predrag Spasic.  Very helpful comments and suggestions were received
  from Juergen Schoenwaelder, Joe Salowey, Jon Saperia, Ravi Sahita,
  Bob Moore, Guus Sliepen, T.H. Jonatan and Dave Perkins.

6. Security Considerations

  This document only defines policy-related terms.  It does not
  describe in detail the vulnerabilities of, threats to, or mechanisms
  that protect specific policy implementations or policy-related
  Internet protocols.

7. References

  [DecSupp]    Building Effective Decision Support Systems.  R.
               Sprague, and E. Carleson.  Prentice Hall, 1982.

  [DirServs]   Understanding and Deploying LDAP Directory Services. T.
               Howes, M. Smith, and G. Good.  MacMillan Technical
               Publications, 1999.

  [DMTF]       Common Information Model (CIM) Schema, version 2.x.
               Distributed Management Task Force, Inc. The components
               of the CIM v2.x schema are available via links on the
               following DMTF web page:
               http://www.dmtf.org/standards/standard_cim.php.

  [RFC1633]    Braden, R., Clark, D. and S. Shenker, "Integrated
               Services in the Internet Architecture: An Overview", RFC
               1633, June 1994.

  [RFC2026]    Bradner, S., "The Internet Standards Process -- Revision
               3", BCP 9, RFC 2026, October 1996.

  [RFC2138]    Rigney, C., Rubens, A., Simpson, W. and S. Willens,
               "Remote Authentication Dial In User Service (RADIUS)",
               RFC 2138, April 1997.

  [RFC2205]    Braden, R., Zhang, L., Berson, S., Herzog, S. and S.
               Jamin, "Resource ReSerVation Protocol (RSVP) -- Version
               1 Functional Specification", RFC 2205, September 1997.





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  [RFC2216]    Shenker, S. and J. Wroclawski, "Network Element Service
               Specification Template", September 1997.

  [RFC2474]    Nichols, K., Blake, S., Baker, F. and D. Black,
               "Definition of the Differentiated Services Field (DS
               Field) in the IPv4 and IPv6 Headers", RFC 2474, December
               1998.

  [RFC2475]    Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.
               and W. Weiss, "An Architecture for Differentiated
               Service", RFC 2475, December 1998.

  [RFC2570]    Case, J., Mundy, R., Partain, D. and B. Stewart,
               "Introduction to Version 3 of the Internet-standard
               Network Management Framework", RFC 2570, April 1999.

  [RFC2578]    McCloghrie, K., Perkins, D., Schoenwaelder, J., Case,
               J., Rose, M. and S.Waldbusser, "Structure of Management
               Information Version 2 (SMIv2)", RFC 2578, April 1999.

  [RFC2702]    Awduche, D., Malcolm, J., Agogbua, J., O'Dell, M. and J.
               McManus, "Requirements for Traffic Engineering Over
               MPLS", RFC 2702, September 1999.

  [RFC2748]    Durham, D., Boyle, J., Cohen, R., Herzog, S., Rajan, R.
               and A. Sastry, "The COPS (Common Open Policy Service)
               Protocol", RFC 2748, January 2000.

  [RFC2749]    Herzog, S., Boyle, J., Cohen, R., Durham, D., Rajan, R.
               and A. Sastry, "COPS Usage for RSVP", RFC 2749, January
               2000.

  [RFC2753]    Yavatkar, R., Pendarakis, D. and R. Guerin, "A Framework
               for Policy-based Admission Control", RFC 2753, January
               2000.

  [RFC2828]    Shirey, R., "Internet Security Glossary", FYI 36, RFC
               2828, May 2000.

  [RFC3060]    Moore, B., Ellesson, E., Strassner, J. and A.
               Westerinen, "Policy Core Information Model -- Version 1
               Specification", RFC 3060, February 2001.

  [RFC3084]    Chan, K., Seligson, J., Durham, D., Gai, S., McCloghrie,
               K., Herzog, S., Reichmeyer, F., Yavatkar, R. and A.
               Smith, "COPS Usage for Policy Provisioning (COPS-PR)",
               RFC 3084, February 2001.




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RFC 3198        Terminology for Policy-Based Management    November 2001


  [RFC3159]    McCloghrie, K., Fine, M., Seligson, J., Chan, K., Hahn,
               S., Sahita, R., Smith, A. and F. Reichmeyer, "Structure
               of Policy Provisioning Information," RFC 3159, August
               2001.

  [UML]        The Unified Modeling Language User Guide.  G. Booch, J.
               Rumbaugh, and I. Jacobson.  Addison-Wesley, 1999.

  [X.500]      Data Communications Networks Directory, Recommendations
               X.500-X.521, Volume VIII - Fascicle VIII.8.  CCITT, IXth
               Plenary Assembly, Melbourne.  November 1988.

8. Authors' Addresses

  Andrea Westerinen
  Cisco Systems, Bldg 20
  725 Alder Drive
  Milpitas, CA 95035

  EMail: [email protected]


  John Schnizlein
  Cisco Systems
  9123 Loughran Road
  Fort Washington, MD  20744

  EMail: [email protected]


  John Strassner
  Intelliden Corporation
  90 South Cascade Avenue
  Colorado Springs, CO  80903
  Phone:   +1-719-785-0648

  EMail:   [email protected]


  Mark Scherling
  Xcert International Inc.
  Suite 300
  505 Burrard Street
  Vancouver, BC
  V7X 1M3

  EMail: [email protected]




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  Bob Quinn
  Celox Networks
  2 Park Central Drive
  Southborough, MA 01772

  EMail: [email protected]


  Jay Perry
  Network Appliance
  495 East Java Drive
  Sunnyvale, CA 94089

  EMail: [email protected]


  Shai Herzog
  PolicyConsulting.com
  200 Clove Rd.
  New Rochelle, NY 10801

  EMail: [email protected]


  An-Ni Huynh
  Lucent Technologies
  2139 Route 35
  Holmdel, NJ 07733


  Mark Carlson
  Sun Microsystems, Inc.
  500 Eldorado Boulevard
  Broomfield, CO 80021

  EMail: [email protected]


  Steve Waldbusser

  Phone: +1-650-948-6500
  Fax:   +1-650-745-0671
  EMail: [email protected]








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9. Full Copyright Statement

  Copyright (C) The Internet Society (2001).  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain it
  or assist in its implementation may be prepared, copied, published
  and distributed, in whole or in part, without restriction of any
  kind, provided that the above copyright notice and this paragraph are
  included on all such copies and derivative works.  However, this
  document itself may not be modified in any way, such as by removing
  the copyright notice or references to the Internet Society or other
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
  BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
  HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
  MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.



















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