A YANG Data Model for Routing Policy ManagementHuawei2330 Central ExpresswaySanta ClaraCA 95050USAyingzhen.qu@huawei.comNuage Networksjefftant.ietf@gmail.comCisco301 Mindenhall WayCaryNC27513USacee@cisco.comJabil8281 Greensboro Drive, Suite 200McleanVA22102USxufeng_liu@jabil.comGoogle1600 Amphitheatre PkwyMountain ViewCA94043USaashaikh@google.com
Routing
RTGWGThis document defines a YANG data model for configuring and
managing routing policies in a vendor-neutral way and based on
actual operational practice. The model provides a generic policy
framework which can be augmented with protocol-specific policy
configuration.
This document describes a YANG data model for routing policy configuration based on operational
usage and best practices in a variety of service provider
networks. The model is intended to be vendor-neutral, in order
to allow operators to manage policy configuration in a
consistent, intuitive way in heterogeneous
environments with routers supplied by multiple vendors.
The YANG modules in this document conform to the Network Management Datastore
Architecture (NMDA).
This model does not aim to be feature complete -- it is a
subset of the policy configuration parameters available
in a variety of vendor implementations, but supports widely
used constructs for managing how routes are imported,
exported, and modified across different routing protocols.
The model development approach has been to examine actual
policy configurations in use across a number of operator
networks. Hence the focus is on enabling policy configuration
capabilities and structure that are in wide use.
Despite the differences in details of policy expressions and
conventions in various vendor implementations, the model
reflects the observation that a relatively simple condition-action
approach can be readily mapped to several existing vendor
implementations, and also gives operators an intuitive and
straightforward way to express policy without sacrificing
flexibility. A side affect of this design decision is that
legacy methods for expressing policies are not considered. Such
methods could be added as an augmentation to the model if
needed.
Consistent with the goal to produce a data model that is vendor
neutral, only policy expressions that are deemed to be widely
available in existing major implementations are included in the
model. Those configuration items that are only available from
a single implementation are omitted from the model with the
expectation they will be available in separate vendor-provided
modules that augment the current model.
The routing policy module has three main parts:
A generic framework to express policies as sets of related
conditions and actions. This includes match sets and actions
that are useful across many routing protocols.
A structure that allows routing protocol models to add
protocol-specific policy conditions and actions though
YANG augmentations. There is a complete example of this
for BGP policies in the proposed vendor-neutral
BGP data model.
A reusable grouping for attaching import and export rules in
the context of routing configuration for different
protocols, VRFs, etc. This also enables creation of policy
chains and expressing default policy behavior.
The module makes use of the standard Internet types,
such as IP addresses, autonomous system numbers, etc.,
defined in RFC 6991.
Policies are expressed as a sequence of top-level policy
definitions each of which consists of a sequence of policy statements.
Policy statements in turn consist of simple condition-action
tuples. Conditions may include multiple match or comparison
operations, and similarly, actions may effect multiple changes to
route attributes, or indicate a final disposition of accepting
or rejecting the route. This structure is shown below.
+--rw routing-policy
+--rw policy-definitions
+--rw policy-definition* [name]
+--rw name string
+--rw statements
+--rw statement* [name]
+--rw name string
+--rw conditions
| ...
+--rw actions
...
The models provides a set of generic sets that can be used for
matching in policy conditions. These sets are applicable for
route selection across multiple routing protocols. They may be
further augmented by
protocol-specific models which have their own defined sets. The
supported defined sets include:
prefix sets - define a set of IP prefixes, each with an
associated CIDR netmask range (or exact length)
neighbor sets - define a set of neighboring nodes by their
IP addresses. These sets are used for selecting routes based on the
neighbors advertising the routes.
tag set - define a set of generic tag values that can be used
in matches for filtering routes
The model structure for defined sets is shown below.
+--rw routing-policy
+--rw defined-sets
| +--rw prefix-sets
| | +--rw prefix-set* [name]
| | +--rw name string
| | +--rw mode? enumeration
| | +--rw prefixes
| | +--rw prefix* [ip-prefix masklength-range]
| | +--rw ip-prefix inet:ip-prefix
| | +--rw masklength-range string
| +--rw neighbor-sets
| | +--rw neighbor-set* [name]
| | +--rw name string
| | +--rw address* inet:ip-address
| +--rw tag-sets
| +--rw tag-set* [name]
| +--rw name string
| +--rw tag-value* tag-type
Policy statements consist of a set of conditions and actions
(either of which may be empty). Conditions are used to
match route attributes against a defined set (e.g., a prefix
set), or to compare attributes against a specific value.
Match conditions may be further modified using the
match-set-options configuration which allows operators to
change the behavior of a match. Three options are supported:
ALL - match is true only if the given value matches
all members of the set.
ANY - match is true if the given value matches any
member of the set.
INVERT - match is true if the given value does not
match any member of the given set.
Not all options are appropriate for matching against all
defined sets (e.g., match ALL in a prefix set does not make sense).
In the model, a restricted set of match options is used where
applicable.
Comparison conditions may similarly use options to change how
route attributes should be tested, e.g., for equality or
inequality, against a given value.
While most policy conditions will be added by individual
routing protocol models via augmentation, this routing policy
model includes several generic match conditions and also the
ability to test which protocol or mechanism installed a route
(e.g., BGP, IGP, static, etc.). The conditions included in
the model are shown below.
+--rw routing-policy
+--rw policy-definitions
+--rw policy-definition* [name]
+--rw name string
+--rw statements
+--rw statement* [name]
+--rw conditions
| +--rw call-policy?
| +--rw install-protocol-eq?
| +--rw match-interface
| | +--rw interface?
| +--rw match-prefix-set
| | +--rw prefix-set?
| | +--rw match-set-options?
| +--rw match-neighbor-set
| | +--rw neighbor-set?
| | +--rw match-set-options?
| | match-set-options-restricted-type
| +--rw match-tag-set
| +--rw tag-set?
| +--rw match-set-options?
match-set-options-restricted-type
When policy conditions are satisfied, policy actions are used
to set various attributes of the route being processed, or to
indicate the final disposition of the route, i.e., accept or
reject.
Similar to policy conditions, the routing policy model includes
generic actions in addition to the basic route
disposition actions. These are shown below.
+--rw routing-policy
+--rw policy-definitions
+--rw policy-definition* [name]
+--rw statements
+--rw statement* [name]
+--rw actions
+--rw policy-result? policy-result-type
Policy 'subroutines' (or nested policies) are
supported by allowing policy statement conditions to reference
other policy definitions using the call-policy configuration.
Called policies apply their conditions and
actions before returning to the calling policy statement and
resuming evaluation. The outcome of the called policy affects
the evaluation of the calling policy. If the called policy
results in an accept-route (either explicit or by default),
then the subroutine returns an effective boolean true value to
the calling policy. For the calling policy, this is equivalent
to a condition statement evaluating to a true value and
evaluation of the policy continues
(see ). Note that
the called policy may also modify attributes of the route in
its action statements. Similarly, a reject-route action
returns false and the calling policy evaluation will be
affected accordingly. Consequently, a subroutine cannot
explicitly accept or reject a route. Rather it merely provides
an indication that 'call-policy' condition returns boolean true
or false indicating whether or not the condition matches. Route
acceptance or rejection is solely determined by the top-level
policy.
Note that the called policy may itself call other policies (subject
to implementation limitations). The model does not prescribe a
nesting depth because this varies among implementations. For example,
some major implementation may only support a single level of
subroutine recursion. As with any routing policy construction, care
must be taken with nested policies to ensure that the effective
return value results in the intended behavior. Nested policies
are a convenience in many routing policy constructions but
creating policies nested beyond a small number of levels (e.g., 2-3)
should be discouraged.
Evaluation of each policy definition proceeds by evaluating its
corresponding individual policy statements in order. When a
condition statement in a policy statement is satisfied, the
corresponding action statement is executed. If the action
statement has either accept-route or reject-route actions,
evaluation of the current policy definition stops, and no further
policy definitions in the chain are evaluated.
If the condition is not satisfied, then evaluation proceeds to
the next policy statement. If none of the policy statement
conditions are satisfied, then evaluation of the current policy
definition stops, and the next policy definition in the chain is
evaluated. When the end of the policy chain is reached, the
default route disposition action is performed (i.e., reject-route
unless an alternate default action is specified for the
chain).
Routing policy is applied by defining and attaching policy chains
in various routing contexts. Policy chains are sequences of
policy definitions (described in ) that have an associated direction (import or export)
with respect to the routing context in which they are defined.
The routing policy model defines an apply-policy grouping that
can be imported and used by other models. As shown below, it
allows definition of import and export policy chains, as well as
specifying the default route disposition to be used when no
policy definition in the chain results in a final decision.
+--rw apply-policy
| +--rw import-policy*
| +--rw default-import-policy? default-policy-type
| +--rw export-policy*
| +--rw default-export-policy? default-policy-type
The default policy defined by the model is to reject the route for
both import and export policies.
Routing models that require the ability to apply routing policy
may augment the routing policy model with protocol or other
specific policy configuration. The routing policy model
assumes that additional defined sets, conditions, and actions
may all be added by other models.
An example of this is shown below, in which the BGP configuration
model in
adds new defined sets to match on community values or AS paths.
The model similarly augments BGP-specific conditions and actions
in the corresponding sections of the routing policy model.
+--rw routing-policy
+--rw defined-sets
+--rw prefix-sets
| +--rw prefix-set* [prefix-set-name]
| +--rw prefix-set-name
| +--rw prefix* [ip-prefix masklength-range]
| +--rw ip-prefix
| +--rw masklength-range
+--rw neighbor-sets
| +--rw neighbor-set* [neighbor-set-name]
| +--rw neighbor-set-name
| +--rw neighbor* [address]
| +--rw address
+--rw tag-sets
| +--rw tag-set* [tag-set-name]
| +--rw tag-set-name
| +--rw tag* [value]
| +--rw value
+--rw bgp-pol:bgp-defined-sets
+--rw bgp-pol:community-sets
| +--rw bgp-pol:community-set* [community-set-name]
| +--rw bgp-pol:community-set-name
| +--rw bgp-pol:community-member*
+--rw bgp-pol:ext-community-sets
| +--rw bgp-pol:ext-community-set*
| [ext-community-set-name]
| +--rw bgp-pol:ext-community-set-name
| +--rw bgp-pol:ext-community-member*
+--rw bgp-pol:as-path-sets
+--rw bgp-pol:as-path-set* [as-path-set-name]
+--rw bgp-pol:as-path-set-name
+--rw bgp-pol:as-path-set-member*
Routing policy configuration has a significant impact on network operations,
and, as such, any related model carries potential security risks.
YANG data models are generally designed to be used with the
NETCONF protocol over an SSH transport. This provides an
authenticated and secure channel over which to transfer
configuration and operational data. Note that use of
alternate transport or data encoding (e.g., JSON over HTTPS)
would require similar mechanisms for authenticating and
securing access to configuration data.
Most of the data elements in the policy model could be
considered sensitive from a security standpoint. Unauthorized
access or invalid data could cause major disruption.
This YANG data model and the component modules currently use
a temporary ad-hoc namespace. If and when it is placed on redirected for
the standards track, an appropriate namespace URI will be
registered in the IETF XML Registry".
The routing policy YANG modules will be registered in the
"YANG Module Names" registry [RFC6020].
The routing policy model is described by the YANG modules in the
sections below.
file "ietf-routing-policy@2018-02-26.yang"
module ietf-routing-policy {
yang-version "1.1";
namespace "urn:ietf:params:xml:ns:yang:ietf-routing-policy";
prefix rt-pol;
import ietf-inet-types {
prefix "inet";
}
import ietf-yang-types {
prefix "yang";
}
import ietf-interfaces {
prefix "if";
}
import ietf-routing {
prefix "rt";
}
import ietf-interfaces-common {
prefix if-cmn;
}
import ietf-if-l3-vlan {
prefix "if-l3-vlan";
}
organization
"IETF RTGWG - Routing Area Working Group";
contact
"WG Web:
WG List:
Editor: Yingzhen Qu
Jeff Tantsura
Acee Lindem
Xufeng Liu
Anees Shaikh
";
description
"This module describes a YANG model for routing policy
configuration. It is a limited subset of all of the policy
configuration parameters available in the variety of vendor
implementations, but supports widely used constructs for
managing how routes are imported, exported, and modified across
different routing protocols. This module is intended to be used
in conjunction with routing protocol configuration modules
(e.g., BGP) defined in other models.
Route policy expression:
Policies are expressed as a set of top-level policy definitions,
each of which consists of a sequence of policy statements.
Policy statements consist of simple condition-action tuples.
Conditions may include mutiple match or comparison operations,
and similarly actions may be multitude of changes to route
attributes or a final disposition of accepting or rejecting the
route.
Route policy evaluation:
Policy definitions are referenced in routing protocol
configurations using import and export configuration statements.
The arguments are members of an ordered list of named policy
definitions which comprise a policy chain, and optionally, an
explicit default policy action (i.e., reject or accept).
Evaluation of each policy definition proceeds by evaluating its
corresponding individual policy statements in order. When a
condition statement in a policy statement is satisfied, the
corresponding action statement is executed. If the action
statement has either accept-route or reject-route actions,
policy evaluation of the current policy definition stops, and
no further policy definitions in the chain are evaluated.
If the condition is not satisfied, then evaluation proceeds to
the next policy statement. If none of the policy statement
conditions are satisfied, then evaluation of the current policy
definition stops, and the next policy definition in the chain is
evaluated. When the end of the policy chain is reached, the
default route disposition action is performed (i.e.,
reject-route unless an alternate default action is specified
for the chain).
Policy 'subroutines' (or nested policies) are supported by
allowing policy statement conditions to reference another policy
definition which applies conditions and actions from the
referenced policy before returning to the calling policy
statement and resuming evaluation. If the called policy
results in an accept-route (either explicit or by default), then
the subroutine returns an effective true value to the calling
policy. Similarly, a reject-route action returns false. If the
subroutine returns true, the calling policy continues to
evaluate the remaining conditions (using a modified route if the
subroutine performed any changes to the route).";
revision "2018-02-26" {
description
"Initial revision.";
reference
"RFC XXXX: Routing Policy Configuration Model for Service
Provider Networks";
}
// typedef statements
typedef default-policy-type {
// this typedef retained for name compatibiity with default
// import and export policy
type enumeration {
enum accept-route {
description
"Default policy to accept the route";
}
enum reject-route {
description
"Default policy to reject the route";
}
}
description
"Type used to specify route disposition in
a policy chain";
}
typedef policy-result-type {
type enumeration {
enum accept-route {
description "Policy accepts the route";
}
enum reject-route {
description "Policy rejects the route";
}
}
description
"Type used to specify route disposition in
a policy chain";
}
typedef tag-type {
type union {
type uint32;
type yang:hex-string;
}
description "Type for expressing route tags on a local system,
including IS-IS and OSPF; may be expressed as either decimal
or hexadecimal integer";
reference
"RFC 2178 - OSPF Version 2
RFC 5130 - A Policy Control Mechanism in IS-IS Using
Administrative Tags";
}
typedef match-set-options-type {
type enumeration {
enum any {
description "Match is true if given value matches any member
of the defined set";
}
enum all {
description "Match is true if given value matches all
members of the defined set";
}
enum invert {
description "Match is true if given value does not match any
member of the defined set";
}
}
default any;
description
"Options that govern the behavior of a match statement. The
default behavior is any, i.e., the given value matches any
of the members of the defined set";
}
// grouping statements
grouping prefix-set {
description
"Configuration data for prefix sets used in policy
definitions.";
leaf name {
type string;
description
"Name of the prefix set -- this is used as a label to
reference the set in match conditions";
}
leaf mode {
type enumeration {
enum ipv4 {
description
"Prefix set contains IPv4 prefixes only";
}
enum ipv6 {
description
"Prefix set contains IPv6 prefixes only";
}
enum mixed {
description
"Prefix set contains mixed IPv4 and IPv6 prefixes";
}
}
description
"Indicates the mode of the prefix set, in terms of which
address families (IPv4, IPv6, or both) are present. The
mode provides a hint, but the device must validate that all
prefixes are of the indicated type, and is expected to
reject the configuration if there is a discrepancy. The
MIXED mode may not be supported on devices that require
prefix sets to be of only one address family.";
}
}
grouping prefix-set-top {
description
"Top-level data definitions for a list of IPv4 or IPv6
prefixes which are matched as part of a policy";
container prefix-sets {
description
"Enclosing container ";
list prefix-set {
key "name";
description
"List of the defined prefix sets";
uses prefix-set;
uses prefix-top;
}
}
}
grouping prefix {
description
"Configuration data for a prefix definition";
leaf ip-prefix {
type inet:ip-prefix;
mandatory true;
description
"The prefix member in CIDR notation -- while the
prefix may be either IPv4 or IPv6, most
implementations require all members of the prefix set
to be the same address family. Mixing address types in
the same prefix set is likely to cause an error.";
}
leaf masklength-range {
type string {
pattern '([0-9]{2}\.\.[0-9]{2})|([0-9]{2})';
}
description
"Defines a range for the masklength, or 'exact' if
the prefix has an exact length.
Example: 10.3.192.0/21 through 10.3.192.0/24 would be
expressed as prefix: 10.3.192.0/21,
masklength-range: 21..24.
Example: 10.3.192.0/21 would be expressed as
prefix: 10.3.192.0/21,
masklength-range: exact";
}
}
grouping prefix-top {
description
"Top-level grouping for prefixes in a prefix list";
container prefixes {
description
"Enclosing container for the list of prefixes in a policy
prefix list";
list prefix-list {
key "ip-prefix masklength-range";
description
"List of prefixes in the prefix set";
uses prefix;
}
}
}
grouping neighbor-set {
description
"This grouping provides neighbor set definitions";
leaf name {
type string;
description
"Name of the neighbor set -- this is used as a label
to reference the set in match conditions";
}
leaf-list address {
type inet:ip-address;
description
"List of IP addresses in the neighbor set";
}
}
grouping neighbor-set-top {
description
"Top-level data definition for a list of IPv4 or IPv6
neighbors which can be matched in a routing policy";
container neighbor-sets {
description
"Enclosing container for the list of neighbor set
definitions";
list neighbor-set {
key "name";
description
"List of defined neighbor sets for use in policies.";
uses neighbor-set;
}
}
}
grouping tag-set {
description
"This grouping provides tag set definitions.";
leaf name {
type string;
description
"Name of the tag set -- this is used as a label to reference
the set in match conditions";
}
leaf-list tag-value {
type tag-type;
description
"Value of the tag set member";
}
}
grouping tag-set-top {
description
"Top-level data definitions for a list of tags which can
be matched in policies";
container tag-sets {
description
"Enclosing container for the list of tag sets.";
list tag-set {
key "name";
description
"List of tag set definitions.";
uses tag-set;
}
}
}
grouping match-set-options-group {
description
"Grouping containing options relating to how a particular set
should be matched";
leaf match-set-options {
type match-set-options-type;
description
"Optional parameter that governs the behavior of the
match operation";
}
}
grouping match-set-options-restricted-group {
description
"Grouping for a restricted set of match operation modifiers";
leaf match-set-options {
type match-set-options-type {
enum any {
description "Match is true if given value matches any
member of the defined set";
}
enum invert {
description "Match is true if given value does not match
any member of the defined set";
}
}
description
"Optional parameter that governs the behavior of the
match operation. This leaf only supports matching on ANY
member of the set or inverting the match. Matching on ALL
is not supported";
}
}
grouping match-interface-condition {
description
"This grouping provides interface match condition";
container match-interface {
leaf interface {
type leafref {
path "/if:interfaces/if:interface/if:name";
}
description
"Reference to a base interface. If a reference to a
subinterface is required, this leaf must be specified
to indicate the base interface.";
}
leaf subinterface {
type leafref {
path "/if:interfaces/if:interface/if-cmn:encapsulation"
+ "/if-l3-vlan:dot1q-vlan"
+ "/if-l3-vlan:outer-tag/if-l3-vlan:vlan-id";
}
description
"Reference to a subinterface -- this requires the base
interface to be specified using the interface leaf in
this container. If only a reference to a base interface
is requuired, this leaf should not be set.";
}
description
"Container for interface match conditions";
}
}
grouping prefix-set-condition {
description
"This grouping provides prefix-set conditions";
container match-prefix-set {
leaf prefix-set {
type leafref {
path "../../../../../../../defined-sets/" +
"prefix-sets/prefix-set/name";
}
description "References a defined prefix set";
}
uses match-set-options-restricted-group;
description
"Match a referenced prefix-set according to the logic
defined in the match-set-options leaf";
}
}
grouping neighbor-set-condition {
description
"This grouping provides neighbor-set conditions";
container match-neighbor-set {
leaf neighbor-set {
type leafref {
path "../../../../../../../defined-sets/neighbor-sets/" +
"neighbor-set/name";
require-instance true;
}
description "References a defined neighbor set";
}
description
"Match a referenced neighbor set according to the logic
defined in the match-set-options-leaf";
}
}
grouping tag-set-condition {
description
"This grouping provides tag-set conditions";
container match-tag-set {
leaf tag-set {
type leafref {
path "../../../../../../../defined-sets/tag-sets/tag-set" +
"/name";
require-instance true;
}
description "References a defined tag set";
}
uses match-set-options-restricted-group;
description
"Match a referenced tag set according to the logic defined
in the match-options-set leaf";
}
}
grouping generic-conditions {
description "Condition statement definitions for checking
membership in a generic defined set";
uses match-interface-condition;
uses prefix-set-condition;
uses neighbor-set-condition;
uses tag-set-condition;
}
grouping generic-actions {
description
"Definitions for common set of policy action statements that
manage the disposition or control flow of the policy";
leaf policy-result {
type policy-result-type;
description
"Select the final disposition for the route, either
accept or reject.";
}
}
grouping policy-conditions {
description
"Data for general policy conditions, i.e., those
not related to match-sets";
leaf call-policy {
type leafref {
path "../../../../../../" +
"rt-pol:policy-definitions/" +
"rt-pol:policy-definition/rt-pol:name";
require-instance true;
}
description
"Applies the statements from the specified policy
definition and then returns control the current
policy statement. Note that the called policy may
itself call other policies (subject to
implementation limitations). This is intended to
provide a policy 'subroutine' capability. The
called policy should contain an explicit or a
default route disposition that returns an
effective true (accept-route) or false
(reject-route), otherwise the behavior may be
ambiguous and implementation dependent";
}
leaf install-protocol-eq {
type identityref {
base rt:control-plane-protocol;
}
description
"Condition to check the protocol / method used to install
the route into the local routing table";
}
}
grouping policy-conditions-top {
description
"Top-level grouping for policy conditions";
container conditions {
description
"Condition statements for the current policy statement";
uses policy-conditions;
uses generic-conditions;
}
}
grouping policy-statements {
description
"Data for policy statements";
leaf name {
type string;
description
"Name of the policy statement";
}
}
grouping policy-actions {
description
"Grouping for policy actions";
uses generic-actions;
}
grouping policy-actions-top {
description
"Top-level grouping for policy actions";
container actions {
description
"Top-level container for policy action statements";
uses policy-actions;
}
}
grouping policy-statements-top {
description
"Top-level grouping for the policy statements list";
container statements {
description
"Enclosing container for policy statements";
list statement {
key "name";
ordered-by user;
description
"Policy statements group conditions and actions
within a policy definition. They are evaluated in
the order specified (see the description of policy
evaluation at the top of this module.";
uses policy-statements;
uses policy-conditions-top;
uses policy-actions-top;
}
}
}
grouping policy-definitions {
description
"This grouping provides policy definitions";
leaf name {
type string;
description
"Name of the top-level policy definition -- this name
is used in references to the current policy";
}
}
grouping apply-policy-import {
description
"Grouping for applying import policies";
leaf-list import-policy {
type leafref {
path "/rt-pol:routing-policy/rt-pol:policy-definitions/" +
"rt-pol:policy-definition/rt-pol:name";
require-instance true;
}
ordered-by user;
description
"List of policy names in sequence to be applied on
receiving a routing update in the current context, e.g.,
for the current peer group, neighbor, address family,
etc.";
}
leaf default-import-policy {
type default-policy-type;
default reject-route;
description
"Explicitly set a default policy if no policy definition
in the import policy chain is satisfied.";
}
}
grouping apply-policy-export {
description
"Grouping for applying export policies";
leaf-list export-policy {
type leafref {
path "/rt-pol:routing-policy/rt-pol:policy-definitions/" +
"rt-pol:policy-definition/rt-pol:name";
require-instance true;
}
ordered-by user;
description
"List of policy names in sequence to be applied on
sending a routing update in the current context, e.g.,
for the current peer group, neighbor, address family,
etc.";
}
leaf default-export-policy {
type default-policy-type;
default reject-route;
description
"Explicitly set a default policy if no policy definition
in the export policy chain is satisfied.";
}
}
grouping apply-policy {
description
"Configuration data for routing policies";
uses apply-policy-import;
uses apply-policy-export;
container apply-policy-state {
description
"Operational state associated with routing policy";
//TODO: identify additional state data beyond the intended
//policy configuration.
}
}
grouping apply-policy-group {
description
"Top level container for routing policy applications. This
grouping is intended to be used in routing models where
needed.";
container apply-policy {
description
"Anchor point for routing policies in the model.
Import and export policies are with respect to the local
routing table, i.e., export (send) and import (receive),
depending on the context.";
uses apply-policy;
}
}
container routing-policy {
description
"Top-level container for all routing policy";
container defined-sets {
description
"Predefined sets of attributes used in policy match
statements";
uses prefix-set-top;
uses neighbor-set-top;
uses tag-set-top;
}
container policy-definitions {
description
"Enclosing container for the list of top-level policy
definitions";
list policy-definition {
key "name";
description
"List of top-level policy definitions, keyed by unique
name. These policy definitions are expected to be
referenced (by name) in policy chains specified in import
or export configuration statements.";
uses policy-definitions;
uses policy-statements-top;
}
}
}
}
]]>
Below we show an example of XML-encoded configuration data using
the routing policy and BGP models to illustrate both how policies
are defined, and also how they can be applied. Note that the XML
has been simplified for readability.
]]>
YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)Tail-f SystemsA Border Gateway Protocol 4 (BGP-4)Common YANG Data TypesJacobs UniversityThe IETF XML RegistryVerisign, Inc.The routing policy module defined in this draft is based on the OpenConfig
route policy model. The authors would like to thank to OpenConfig for their contributions,
especially Rob Shakir, Kevin D'Souza, and Chris Chase.
The authors are grateful for valuable contributions to this
document and the associated models from: Ebben Aires, Luyuan Fang,
Josh George, Acee Lindem, Stephane Litkowski, Ina Minei,
Carl Moberg, Eric Osborne, Steve Padgett, Juergen Schoenwaelder,
Jim Uttaro, and Russ White.
Updated the model to use IETF modules and be NMDA compliant.
Updated policy model with additional condition for matching interfaces.
This revision updates the draft name to reflect adoption as a working
document in the RTGWG. Minor changes include updates to references
and updated author contact information.