Terminology for Policy-Based Management
RFC 3198
| Document | Type | RFC - Informational (November 2001) | |
|---|---|---|---|
| Authors | Steven Waldbusser , Jay Perry , Shai Herzog , Mark A. Carlson , Dr. John M. Schnizlein , Bob Quinn , Mark Scherling , Andrea Westerinen , Anni Huynh , John Strassner | ||
| Last updated | 2013-03-02 | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Stream | WG state | (None) | |
| Document shepherd | (None) | ||
| IESG | IESG state | RFC 3198 (Informational) | |
| Consensus boilerplate | Unknown | ||
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
RFC 3198
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.
Westerinen, et al. Informational [Page 17]
RFC 3198 Terminology for Policy-Based Management November 2001
[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.
Westerinen, et al. Informational [Page 18]
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: andreaw@cisco.com
John Schnizlein
Cisco Systems
9123 Loughran Road
Fort Washington, MD 20744
EMail: john.schnizlein@cisco.com
John Strassner
Intelliden Corporation
90 South Cascade Avenue
Colorado Springs, CO 80903
Phone: +1-719-785-0648
EMail: john.strassner@intelliden.com
Mark Scherling
Xcert International Inc.
Suite 300
505 Burrard Street
Vancouver, BC
V7X 1M3
EMail: mscherling@xcert.com
Westerinen, et al. Informational [Page 19]
RFC 3198 Terminology for Policy-Based Management November 2001
Bob Quinn
Celox Networks
2 Park Central Drive
Southborough, MA 01772
EMail: bquinn@celoxnetworks.com
Jay Perry
Network Appliance
495 East Java Drive
Sunnyvale, CA 94089
EMail: jay.perry@netapp.com
Shai Herzog
PolicyConsulting.com
200 Clove Rd.
New Rochelle, NY 10801
EMail: herzog@PolicyConsulting.com
An-Ni Huynh
Lucent Technologies
2139 Route 35
Holmdel, NJ 07733
Mark Carlson
Sun Microsystems, Inc.
500 Eldorado Boulevard
Broomfield, CO 80021
EMail: mark.carlson@sun.com
Steve Waldbusser
Phone: +1-650-948-6500
Fax: +1-650-745-0671
EMail: waldbusser@nextbeacon.com
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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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