[Docs] [txt|pdf|xml|html] [Tracker] [Email] [Diff1] [Diff2] [Nits] [IPR]
Versions: 00 01 02 03
OPSAWG B. Claise
Internet-Draft J. Quilbeuf
Intended status: Standards Track Cisco Systems, Inc.
Expires: July 16, 2020 P. Lucente
NTT
P. Fasano
TIM S.p.A
January 13, 2020
YANG Modules for Service Assurance
draft-claise-opsawg-service-assurance-yang-03
Abstract
This document proposes YANG modules for the Service Assurance for
Intent-based Networking Architecture.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on July 16, 2020.
Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
Claise, et al. Expires July 16, 2020 [Page 1]
Internet-Draft YANG Modules for Service Assurance January 2020
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
3. YANG Models Overview . . . . . . . . . . . . . . . . . . . . 3
4. Base ietf-service-assurance YANG module . . . . . . . . . . . 4
4.1. Tree View . . . . . . . . . . . . . . . . . . . . . . . . 4
4.2. Concepts . . . . . . . . . . . . . . . . . . . . . . . . 4
4.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 6
5. Subservice Extension: ietf-service-assurance-device YANG
module . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.1. Tree View . . . . . . . . . . . . . . . . . . . . . . . . 12
5.2. Complete Tree View . . . . . . . . . . . . . . . . . . . 13
5.3. Concepts . . . . . . . . . . . . . . . . . . . . . . . . 13
5.4. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 14
6. Vendor-specific Subservice Extension: example-service-
assurance-device-acme YANG module . . . . . . . . . . . . . . 16
6.1. Tree View . . . . . . . . . . . . . . . . . . . . . . . . 16
6.2. Complete Tree View . . . . . . . . . . . . . . . . . . . 16
6.3. Concepts . . . . . . . . . . . . . . . . . . . . . . . . 17
6.4. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 18
7. Security Considerations . . . . . . . . . . . . . . . . . . . 19
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20
8.1. The IETF XML Registry . . . . . . . . . . . . . . . . . . 20
8.2. The YANG Module Names Registry . . . . . . . . . . . . . 20
9. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . 20
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 20
10.1. Normative References . . . . . . . . . . . . . . . . . . 20
10.2. Informative References . . . . . . . . . . . . . . . . . 21
Appendix A. Changes between revisions . . . . . . . . . . . . . 21
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 21
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22
1. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
The terms used in this document are defined in draft-claise-opsawg-
service-assurance-architecture IETF draft.
Claise, et al. Expires July 16, 2020 [Page 2]
Internet-Draft YANG Modules for Service Assurance January 2020
2. Introduction
The "Service Assurance for Intent-based Networking Architecture"
draft-claise-opsawg-service-assurance-architecture, specifies the
framework and all of its components for service assurance. This
document complements the architecture by providing open interfaces
between components. More specifically, the goal is to provide YANG
modules for the purpose of service assurance in a format that is:
o machine readable
o vendor independent
o augmentable
3. YANG Models Overview
The main YANG module, ietf-service-assurance, defines objects for
assuring network services based on their decomposition into so-called
subservices. The subservices are hierarchically organised by
dependencies. The subservices, along with the dependencies,
constitute an assurance graph. This module should be supported by an
agent, able to interact with the devices in order to produce a health
status and symptoms for each subservice in the assurance graph. This
module is intended for the following use cases:
o Assurance graph configuration:
* Subservices: configure a set of subservices to assure, by
specifying their types and parameters.
* Dependencies: configure the dependencies between the
subservices, along with their type.
o Assurance telemetry: export the health status of the subservices,
along with the observed symptoms.
The second YANG module, ietf-service-assurance-device, extends the
ietf-service-assurance module to add support for the subservice
DeviceHealthy. Additional subservice types might be added the same
way.
The third YANG module, example-service-assurance-device-acme, extends
the ietf-service-assurance-device module as an example to add support
for the subservice DeviceHealthy, with specifics for the fictional
ACME Corporation. Additional vendor-specific parameters might be
added the same way.
Claise, et al. Expires July 16, 2020 [Page 3]
Internet-Draft YANG Modules for Service Assurance January 2020
4. Base ietf-service-assurance YANG module
4.1. Tree View
The following tree diagram [RFC8340] provides an overview of the
ietf-service-assurance data model.
module: ietf-service-assurance
+--ro assurance-graph-version? yang:counter32
+--ro assurance-graph-last-change? yang:date-and-time
+--rw subservices
+--rw subservice* [type id]
+--rw type identityref
+--rw id string
+--ro last-change? yang:date-and-time
+--ro label? string
+--rw under-maintenance? boolean
+--rw maintenance-contact string
+--rw (parameter)?
| +--:(service-instance-parameter)
| +--rw service-instance-parameter
| +--rw service? string
| +--rw instance-name? string
+--ro health-score? uint8
+--rw symptoms
| +--ro symptom* [start-date-time id]
| +--ro id string
| +--ro health-score-weight? uint8
| +--ro label? string
| +--ro start-date-time yang:date-and-time
| +--ro stop-date-time? yang:date-and-time
+--rw dependencies
+--rw dependency* [type id]
+--rw type -> /subservices/subservice/type
+--rw id -> /subservices/subservice[type=current()/../type]/id
+--rw dependency-type? identityref
4.2. Concepts
The ietf-service-assurance YANG model assumes an identified number of
subservices, to be assured independently. A subservice is a feature
or a subpart of the network system that a given service instance
might depend on. Example of subservices include:
o DeviceHealthy: whether a device is healthy, and if not, what are
the symptoms. Potential symptoms are "CPU overloaded", "Out of
RAM", or "Out of TCAM".
Claise, et al. Expires July 16, 2020 [Page 4]
Internet-Draft YANG Modules for Service Assurance January 2020
o ConnectivityHealthy: given two IP addresses owned by two devices,
what is the quality of the connection between them. Potential
symptoms are "No route available" or "ECMP Imbalance".
The first example is a subservice representing a subpart of the
network system, while the second is a subservice representing a
feature of the network, In both cases, these subservices might depend
on other subservices, for instance, the connectivity might depend on
a subservice representing the routing mechanism and on a subservice
representing ECMP.
The symptoms are listed for each subservice. Each symptom is
specified by a unique id and contains a health-score-weight (the
impact to the health score incurred by this symptom), a label (text
describing what the symptom is), and dates and times at which the
symptom was detected and stopped being detected. While the unique id
is sufficient as an unique key list, the start-date-time second key
help sorting and retrieving relevant symptoms.
The assurance of a given service instance can be obtained by
composing the assurance of the subservices that it depends on, via
the dependency relations.
In order to declare a subservice MUST provide:
o A type: identity inheriting of the base identity for subservice,
o An id: string uniquely identifying the subservice among those with
the same identity,
o Some parameters, which should be specified in an augmenting model,
as described in the next sections.
The type and id uniquely identify a given subservice. They are used
to indicate the dependencies. Dependencies have types as well. Two
types are specified in the model:
o Impacting: such a dependency indicates an impact on the health of
the dependent,
o Informational: such a dependency might explain why the dependent
has issues but does not impact its health.
To illustrate the difference between "impacting" and "informational",
consider the subservice InterfaceHealthy, representing a network
interface. If the device to which the network interface belongs goes
down, the network interface will transition to a down state as well.
Therefore, the dependency of InterfaceHealthy towards DeviceHealthy
Claise, et al. Expires July 16, 2020 [Page 5]
Internet-Draft YANG Modules for Service Assurance January 2020
is "impacting". On the other hand, as a the dependency towards the
ECMPLoad subservice, which checks that the load between ECMP remains
ce remains stable throughout time, is only "informational". Indeed,
services might be perfectly healthy even if the load distribution
between ECMP changed. However, such an instability might be a
relevant symptom for diagnosing the root cause of a problem.
Service instances MUST be modeled as a particular type of subservice
with two parameters, a type and an instance name. The type is the
name of the service defined in the network orchestrator, for instance
"point-to-point-l2vpn". The instance name is the name assigned to
the particular instance that we are assuring, for instance the name
of the customer using that instance.
The "under-maintenance" and "maintenance-contact" flags inhibit the
emission of symptoms for that subservice and subservices that depend
on them. See Section 3.7 of
[draft-claise-opsawg-service-assurance-architecture] for a more
detailed discussion.
By specifying service instances and their dependencies in terms of
subservices, one defines the whole assurance to apply for them. An
assurance agent supporting this model should then produce telemetry
in return with, for each subservice: a health-status indicating how
healthy the subservice is and when the subservice is not healthy, a
list of symptoms explaining why the subservice is not healthy.
4.3. YANG Module
<CODE BEGINS> file "ietf-service-assurance@2020-01-13.yang"
mmodule ietf-service-assurance {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-service-assurance";
prefix service-assurance;
import ietf-yang-types {
prefix yang;
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Author: Benoit Claise <mailto:bclaise@cisco.com>
Author: Jean Quilbeuf <mailto:jquilbeu@cisco.com>";
description
Claise, et al. Expires July 16, 2020 [Page 6]
Internet-Draft YANG Modules for Service Assurance January 2020
"This module defines objects for assuring network services based on
their decomposition into so-called subservices, according to the SAIN
(Service Assurance for Intent-based Networking) architecture.
The subservices hierarchically organised by dependencies constitute an
assurance graph. This module should be supported by an assurance agent,
able to interact with the devices in order to produce a health status
and symptoms for each subservice in the assurance graph.
This module is intended for the following use cases:
* Assurance graph configuration:
* subservices: configure a set of subservices to assure, by specifying
their types and parameters.
* dependencies: configure the dependencies between the subservices,
along with their type.
* Assurance telemetry: export the health status of the subservices, along
with the observed symptoms.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
are to be interpreted as described in BCP 14 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.
Copyright (c) 2019 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices.
revision 2020-01-13 {
description
"Added the maintenance window concept.";
reference
"RFC xxxx: Title to be completed";
}
revision 2019-11-16 {
description
"Initial revision.";
Claise, et al. Expires July 16, 2020 [Page 7]
Internet-Draft YANG Modules for Service Assurance January 2020
reference
"RFC xxxx: Title to be completed";
}
identity subservice-idty {
description
"Root identity for all subservice types.";
}
identity service-instance-idty {
base subservice-idty;
description
"Identity representing a service instance.";
}
identity dependency-type {
description
"Base identity for representing dependency types.";
}
identity informational-dependency {
base dependency-type;
description
"Indicates that symptoms of the dependency might be of interest for the
dependent, but the status of the dependency should not have any
impact on the dependent.";
}
identity impacting-dependency {
base dependency-type;
description
"Indicates that the status of the dependency directly impacts the status
of the dependent.";
}
grouping symptom {
description
"Contains the list of symptoms for a specific subservice.";
leaf id {
type string;
description
"A unique identifier for the symptom.";
}
leaf health-score-weight {
type uint8 {
range "0 .. 100";
}
description
Claise, et al. Expires July 16, 2020 [Page 8]
Internet-Draft YANG Modules for Service Assurance January 2020
"The weight to the health score incurred by this symptom. The higher the
value, the more of an impact this symptom has. If a subservice health
score is not 100, there must be at least one symptom with a health
score weight larger than 0.";
}
leaf label {
type string;
description
"Label of the symptom, i.e. text describing what the symptom is, to
be used in a graphical user interfaces. ";
}
leaf start-date-time {
type yang:date-and-time;
description
"Date and time at which the symptom was detected.";
}
leaf stop-date-time {
type yang:date-and-time;
description
"Date and time at which the symptom stopped being detected.";
}
}
grouping subservice-dependency {
description
"Represent a dependency to another subservice.";
leaf type {
type leafref {
path "/subservices/subservice/type";
}
description
"The type of the subservice to refer to (e.g. DeviceHealthy).";
}
leaf id {
type leafref {
path "/subservices/subservice[type=current()/../type]/id";
}
description
"The identifier of the subservice to refer to.";
}
leaf dependency-type {
type identityref {
base dependency-type;
}
description
"Represents the type of dependency (i.e. informational, impacting).";
}
// augment here if more info are needed (i.e. a percentage) depending on the dependency type.
Claise, et al. Expires July 16, 2020 [Page 9]
Internet-Draft YANG Modules for Service Assurance January 2020
}
leaf assurance-graph-version {
type yang:counter32;
config false;
description
"The assurance graph version, which increases by 1 for each new version.";
}
leaf assurance-graph-last-change {
type yang:date-and-time;
config false;
description
"Date and time at which the assurance graph last changed.";
}
container subservices {
description
"Root container for the subservices.";
list subservice {
key "type id";
description
"List of subservice configured.";
leaf type {
type identityref {
base subservice-idty;
}
description
"Name of the subservice, e.g. DeviceHealthy.";
}
leaf id {
type string;
description
"Unique identifier of the subservice instance, for each type.";
}
leaf last-change {
type yang:date-and-time;
config false;
description
"Date and time at which the assurance graph for this subservice
instance last changed.";
}
leaf label {
type string;
config false;
description
"Label of the symptom, i.e. text describing what the symptom is, to
be computer-consumable and be displayed on a human interface.";
}
leaf under-maintenance {
Claise, et al. Expires July 16, 2020 [Page 10]
Internet-Draft YANG Modules for Service Assurance January 2020
type boolean;
default false;
description
"An optional flag indicating whether this particular subservice is under
maintenance. Under this circumstance, the subservice symptoms and the
symptoms of its dependencies in the assurance graph should not be taken
into account. Instead, the subservice should send a 'Under Maintenance'
single symptom.
The operator changing the under-maintenance value must set the
maintenance-contact variable.
When the subservice is not under maintenance any longer, the
under-maintenance flag must return to its default value and
the under-maintenance-owner variable deleted.";
}
leaf maintenance-contact {
when "../under-maintenance";
type string;
mandatory true;
description
"A string used to model an administratively assigned name of the
resource that changed the under-maintenance value to 'true.
It is suggested that this name contain one or more of the following:
IP address, management station name, network manager's name, location,
or phone number. In some cases the agent itself will be the owner of
an entry. In these cases, this string shall be set to a string
starting with 'monitor'.";
}
choice parameter {
description
"Specify the required parameters per subservice type.";
container service-instance-parameter {
when "derived-from-or-self(../type, 'service-instance-idty')";
description
"Specify the parameters of a service instance.";
leaf service {
type string;
description "Name of the service.";
}
leaf instance-name{
type string;
description "Name of the instance for that service.";
}
}
// Other modules can augment their own cases into here
}
Claise, et al. Expires July 16, 2020 [Page 11]
Internet-Draft YANG Modules for Service Assurance January 2020
leaf health-score {
type uint8 {
range "0 .. 100";
}
config false;
description
"Score value of the subservice health. A value of 100 means that
subservice is healthy. A value of 0 means that the subservice is
broken. A value between 0 and 100 means that the subservice is
degraded.";
}
container symptoms {
description
"Symptoms for the subservice.";
list symptom {
key "start-date-time id";
config false;
description
"List of symptoms the subservice. While the start-date-time key is not
necessary per se, this would get the entries sorted by start-date-time
for easy consumption.";
uses symptom;
}
}
container dependencies {
description
"configure the dependencies between the subservices, along with their types.";
list dependency {
key "type id";
description
"List of soft dependencies of the subservice.";
uses subservice-dependency;
}
}
}
}
}
<CODE ENDS>
5. Subservice Extension: ietf-service-assurance-device YANG module
5.1. Tree View
The following tree diagram [RFC8340] provides an overview of the
ietf-service-assurance-device data model.
Claise, et al. Expires July 16, 2020 [Page 12]
Internet-Draft YANG Modules for Service Assurance January 2020
module: ietf-service-assurance-device
augment /service-assurance:subservices/service-assurance:subservice/service-assurance:parameter:
+--rw device-idty
+--rw device? string
5.2. Complete Tree View
The following tree diagram [RFC8340] provides an overview of the
ietf-service-assurance and ietf-service-assurance-device data models.
module: ietf-service-assurance
+--ro assurance-graph-version? yang:counter32
+--ro assurance-graph-last-change? yang:date-and-time
+--rw subservices
+--rw subservice* [type id]
+--rw type identityref
+--rw id string
+--ro last-change? yang:date-and-time
+--ro label? string
+--rw under-maintenance? boolean
+--rw maintenance-contact string
+--rw (parameter)?
| +--:(service-instance-parameter)
| | +--rw service-instance-parameter
| | +--rw service? string
| | +--rw instance-name? string
| +--:(service-assurance-device:device-idty)
| +--rw service-assurance-device:device-idty
| +--rw service-assurance-device:device? string
+--ro health-score? uint8
+--rw symptoms
| +--ro symptom* [start-date-time id]
| +--ro id string
| +--ro health-score-weight? uint8
| +--ro label? string
| +--ro start-date-time yang:date-and-time
| +--ro stop-date-time? yang:date-and-time
+--rw dependencies
+--rw dependency* [type id]
+--rw type -> /subservices/subservice/type
+--rw id -> /subservices/subservice[type=current()/../type]/id
+--rw dependency-type? identityref
5.3. Concepts
As the number of subservices will grow over time, the YANG module is
designed to be extensible. A new subservice type requires the
precise specifications of its type and expected parameters. Let us
Claise, et al. Expires July 16, 2020 [Page 13]
Internet-Draft YANG Modules for Service Assurance January 2020
illustrate the example of the new DeviceHealthy subservice type. As
the name implies, it monitors and reports the device health, along
with some symptoms in case of degradation.
For our DeviceHealthy subservice definitions, the new device-idty is
specified, as an inheritance from the base identity for subservices.
This indicates to the assurance agent that we are now assuring the
health of a device.
The typical parameter for the configuration of the DeviceHealthy
subservice is the name of the device that we want to assure. By
augmenting the parameter choice from ietf-service-assurance YANG
module for the case of the device-idty subservice type, this new
parameter is specified.
5.4. YANG Module
<CODE BEGINS> file "ietf-service-assurance-device@2020-01-13.yang"
module ietf-service-assurance-device {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-service-assurance-device";
prefix service-assurance-device;
import ietf-service-assurance {
prefix "service-assurance";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Author: Benoit Claise <mailto:bclaise@cisco.com>
Author: Jean Quilbeuf <mailto:jquilbeu@cisco.com>";
description
"This module extends the ietf-service-assurance module to add
support for the subservice DeviceHealthy.
Network Device is healthy.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
are to be interpreted as described in BCP 14 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.
Claise, et al. Expires July 16, 2020 [Page 14]
Internet-Draft YANG Modules for Service Assurance January 2020
Copyright (c) 2019 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices. ";
revision 2020-01-13 {
description
"Added the maintenance window concept.";
reference
"RFC xxxx: Title to be completed";
}
revision 2019-11-16 {
description
"Initial revision.";
reference
"RFC xxxx: Title to be completed";
}
identity device-idty {
base service-assurance:subservice-idty;
description "Network Device is healthy.";
}
augment /service-assurance:subservices/service-assurance:subservice/service-assurance:parameter {
description
"Specify the required parameters for a new subservice type";
container device-idty{
when "derived-from-or-self(../service-assurance:type, 'device-idty')";
description
"Specify the required parameters for the device-idty subservice type";
leaf device {
type string;
description "The device to monitor.";
}
}
}
}
Claise, et al. Expires July 16, 2020 [Page 15]
Internet-Draft YANG Modules for Service Assurance January 2020
<CODE ENDS>
6. Vendor-specific Subservice Extension: example-service-assurance-
device-acme YANG module
6.1. Tree View
The following tree diagram [RFC8340] provides an overview of the
example-service-assurance-device-acme data model.
module: example-service-assurance-device-acme
augment /service-assurance:subservices/service-assurance:subservice/service-assurance:parameter:
+--rw acme-device-idty
+--rw device? string
+--rw acme-specific-parameter? string
6.2. Complete Tree View
The following tree diagram [RFC8340] provides an overview of the
ietf-service-assurance, ietf-service-assurance-device, and example-
service-assurance-device-acme data models.
Claise, et al. Expires July 16, 2020 [Page 16]
Internet-Draft YANG Modules for Service Assurance January 2020
module: ietf-service-assurance
+--ro assurance-graph-version? yang:counter32
+--ro assurance-graph-last-change? yang:date-and-time
+--rw subservices
+--rw subservice* [type id]
+--rw type identityref
+--rw id string
+--ro last-change? yang:date-and-time
+--ro label? string
+--rw under-maintenance? boolean
+--rw maintenance-contact string
+--rw (parameter)?
| +--:(service-instance-parameter)
| | +--rw service-instance-parameter
| | +--rw service? string
| | +--rw instance-name? string
| +--:(service-assurance-device:device-idty)
| | +--rw service-assurance-device:device-idty
| | +--rw service-assurance-device:device? string
| +--:(example-service-assurance-device-acme:acme-device-idty)
| +--rw example-service-assurance-device-acme:acme-device-idty
| +--rw example-service-assurance-device-acme:device? string
| +--rw example-service-assurance-device-acme:acme-specific-parameter? string
+--ro health-score? uint8
+--rw symptoms
| +--ro symptom* [start-date-time id]
| +--ro id string
| +--ro health-score-weight? uint8
| +--ro label? string
| +--ro start-date-time yang:date-and-time
| +--ro stop-date-time? yang:date-and-time
+--rw dependencies
+--rw dependency* [type id]
+--rw type -> /subservices/subservice/type
+--rw id -> /subservices/subservice[type=current()/../type]/id
+--rw dependency-type? identityref
6.3. Concepts
Under some circumstances, vendor-specific subservice types might be
required. As an example of this vendor-specific implementation, this
section shows how to augment the ietf-service-assurance-device module
to add support for the subservice DeviceHealthy, specific to the ACME
Corporation. The new parameter is acme-specific-parameter.
Claise, et al. Expires July 16, 2020 [Page 17]
Internet-Draft YANG Modules for Service Assurance January 2020
6.4. YANG Module
module ietf-service-assurance-device {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-service-assurance-device";
prefix service-assurance-device;
import ietf-service-assurance {
prefix "service-assurance";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Author: Benoit Claise <mailto:bclaise@cisco.com>
Author: Jean Quilbeuf <mailto:jquilbeu@cisco.com>";
description
"This module extends the ietf-service-assurance module to add
support for the subservice DeviceHealthy.
Network Device is healthy.
The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
are to be interpreted as described in BCP 14 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.
Copyright (c) 2019 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices. ";
revision 2020-01-13 {
description
"Added the maintenance window concept.";
reference
Claise, et al. Expires July 16, 2020 [Page 18]
Internet-Draft YANG Modules for Service Assurance January 2020
"RFC xxxx: Title to be completed";
}
revision 2019-11-16 {
description
"Initial revision.";
reference
"RFC xxxx: Title to be completed";
}
identity device-idty {
base service-assurance:subservice-idty;
description "Network Device is healthy.";
}
augment /service-assurance:subservices/service-assurance:subservice/service-assurance:parameter {
description
"Specify the required parameters for a new subservice type";
container device-idty{
when "derived-from-or-self(../service-assurance:type, 'device-idty')";
description
"Specify the required parameters for the device-idty subservice type";
leaf device {
type string;
description "The device to monitor.";
}
}
}
}
7. Security Considerations
The YANG module specified in this document defines a schema for data
that is designed to be accessed via network management protocols such
as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer
is the secure transport layer, and the mandatory-to-implement secure
transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer
is HTTPS, and the mandatory-to-implement secure transport is TLS
[RFC8446].
The Network Configuration Access Control Model (NACM) [RFC8341]
provides the means to restrict access for particular NETCONF or
RESTCONF users to a preconfigured subset of all available NETCONF or
RESTCONF protocol operations and content.
TO BE populated according to https://trac.ietf.org/trac/ops/wiki/
yang-security-guidelines
Claise, et al. Expires July 16, 2020 [Page 19]
Internet-Draft YANG Modules for Service Assurance January 2020
8. IANA Considerations
8.1. The IETF XML Registry
This document registers two URIs in the IETF XML registry [RFC3688].
Following the format in [RFC3688], the following registrations are
requested:
URI: urn:ietf:params:xml:ns:yang:ietf-service-assurance
Registrant Contact: The NETCONF WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-service-assurance-device
Registrant Contact: The NETCONF WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
8.2. The YANG Module Names Registry
This document registers two YANG modules in the YANG Module Names
registry [RFC7950]. Following the format in [RFC7950], the the
following registrations are requested:
name: ietf-service-assurance
namespace: urn:ietf:params:xml:ns:yang:ietf-service-assurance
prefix: inc
reference: RFC XXXX
name: ietf-service-assurance-device
namespace: urn:ietf:params:xml:ns:yang:ietf-service-assurance-device
prefix: inc
reference: RFC XXXX
9. Open Issues
-Complete the Security Considerations
10. References
10.1. Normative References
[draft-claise-opsawg-service-assurance-architecture]
Claise, B. and J. Quilbeuf, "draft-claise-opsawg-service-
assurance-architecture", 2019.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
Claise, et al. Expires July 16, 2020 [Page 20]
Internet-Draft YANG Modules for Service Assurance January 2020
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
10.2. Informative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
Appendix A. Changes between revisions
v00 - v01
o Terminology clarifications
o Provide example of impacting versus impacted dependencies
Claise, et al. Expires July 16, 2020 [Page 21]
Internet-Draft YANG Modules for Service Assurance January 2020
Acknowledgements
The authors would like to thank Jan Lindblad for his help during the
design of these YANG modules. The authors would like to thank
Stephane Litkowski and Charles Eckel for their reviews.
Authors' Addresses
Benoit Claise
Cisco Systems, Inc.
De Kleetlaan 6a b1
1831 Diegem
Belgium
Email: bclaise@cisco.com
Jean Quilbeuf
Cisco Systems, Inc.
1, rue Camille Desmoulins
92782 Issy Les Moulineaux
France
Email: jquilbeu@cisco.com
Paolo Lucente
NTT
Siriusdreef 70-72
Hoofddorp, WT 2132
Netherlands
Email: paolo@ntt.net
Paolo Fasano
TIM S.p.A
via G. Reiss Romoli, 274
10148 Torino
Italy
Email: paolo2.fasano@telecomitalia.it
Claise, et al. Expires July 16, 2020 [Page 22]
Html markup produced by rfcmarkup 1.129d, available from
https://tools.ietf.org/tools/rfcmarkup/