Internet Engineering Task Force (IETF) T. Zhou, Ed.

Internet Engineering Task Force (IETF) T. Zhou, Ed.
Request for Comments: 9617 Huawei
Category: Standards Track J. Guichard
ISSN: 2070-1721 Futurewei
F. Brockners
S. Raghavan
Cisco Systems
August 2024

A YANG Data Model for In Situ Operations, Administration, and
Maintenance (IOAM)

Abstract

In situ Operations, Administration, and Maintenance (IOAM) is an
example of an on-path hybrid measurement method. IOAM defines a
method for producing operational and telemetry information that may
be exported using the in-band or out-of-band method. RFCs 9197 and
9326 discuss the data fields and associated data types for IOAM.
This document defines a YANG module for the configuration of IOAM
functions.

Status of This Memo

This is an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.

Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9617.

Copyright Notice

Copyright (c) 2024 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 Revised BSD License text as described in Section 4.e of the
Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.

Table of Contents

1. Introduction
2. Conventions Used in This Document
2.1. Tree Diagrams
3. Design of the IOAM YANG Data Model
3.1. Overview
3.2. Pre-allocated Tracing Profile
3.3. Incremental Tracing Profile
3.4. Direct Export Profile
3.5. Proof of Transit Profile
3.6. Edge-to-Edge Profile
4. IOAM YANG Module
5. Security Considerations
6. IANA Considerations
7. Normative References
Appendix A. An Example of the Incremental Tracing Profile
Appendix B. An Example of the Pre-allocated Tracing Profile
Appendix C. An Example of the Direct Export Profile
Appendix D. An Example of the Proof of Transit Profile
Appendix E. An Example of the Edge-to-Edge Profile
Acknowledgements
Authors' Addresses

1. Introduction

In situ Operations, Administration, and Maintenance (IOAM) is an
example of an on-path hybrid measurement method. IOAM defines a
method for producing operational and telemetry information that may
be exported using the in-band or out-of-band method. The data types
and data formats for IOAM data records have been defined in [RFC9197]
and [RFC9326]. The IOAM data can be embedded in many protocol
encapsulations, such as the Network Service Header (NSH) [RFC9452]
and IPv6.

This document defines a data model for the configuration of IOAM
capabilities using the YANG data modeling language [RFC7950]. This
YANG data model supports five IOAM options, which are as follows:

* Incremental Trace-Option [RFC9197]

* Pre-allocated Trace-Option [RFC9197]

* Direct Export Option [RFC9326]

* Proof of Transit (POT) Option [RFC9197]

* Edge-to-Edge Option [RFC9197]

2. Conventions Used in This Document

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 following terms are defined in [RFC7950] and are used in this
specification:

* augment

* data model

* data node

The terminology for describing YANG data models is found in
[RFC7950].

2.1. Tree Diagrams

Tree diagrams used in this document follow the notation defined in
[RFC8340].

3. Design of the IOAM YANG Data Model

3.1. Overview

The IOAM model is organized as a list of profiles, as shown in the
following figure. Each profile associates with one flow and the
corresponding IOAM information.

module: ietf-ioam
+--rw ioam
+--ro info
| +--ro timestamp-type? identityref
| +--ro available-interface* [if-name]
| +--ro if-name if:interface-ref
+--rw admin-config
| +--rw enabled? boolean
+--rw profiles
+--rw profile* [profile-name]
+--rw profile-name string
+--rw filter
| +--rw filter-type? ioam-filter-type
| +--rw ace-name? -> /acl:acls/acl/aces/ace/name
+--rw protocol-type? ioam-protocol-type
+--rw incremental-tracing-profile {incremental-trace}?
| ...
+--rw preallocated-tracing-profile {preallocated-trace}?
| ...
+--rw direct-export-profile {direct-export}?
| ...
+--rw pot-profile {proof-of-transit}?
| ...
+--rw e2e-profile {edge-to-edge}?

The "info" parameter is a container for all the read-only information
that assists monitoring systems in the interpretation of the IOAM
data.

The "enabled" parameter is an administrative configuration. When it
is set to "true", IOAM configuration is enabled for the system.
Meanwhile, the IOAM data plane functionality is enabled.

The "filter" parameter is used to identify a flow, where the IOAM
profile can apply. There may be multiple filter types. Access
Control Lists (ACLs) [RFC8519] provide a common way to specify a
flow. Each IOAM profile can associate with an ACE (Access Control
Entry). When the matched ACE "forwarding" action is "accept", IOAM
actions MUST be driven by the accepted packets.

The IOAM data can be encapsulated into multiple protocols, e.g., IPv6
[RFC9486] and the NSH [RFC9452]. The "protocol-type" parameter is
used to indicate where IOAM is applied. For example, if "protocol-
type" is set to "ipv6", the IOAM ingress node will encapsulate the
associated flow according to [RFC9486].

In this document, IOAM data includes five encapsulation types, i.e.,
incremental tracing data, pre-allocated tracing data, direct export
data, proof of transit data, and end-to-end data. In practice,
multiple IOAM data types can be encapsulated into the same IOAM
header. The "profile" parameter contains a set of sub-profiles, each
of which relates to one encapsulation type. The configured object
may not support all the sub-profiles. The supported sub-profiles are
indicated by five defined features, i.e., "incremental-trace",
"preallocated-trace", "direct-export", "proof-of-transit", and "edge-
to-edge".

This document uses the "ietf-access-control-list" YANG module
[RFC8519], the "ietf-interfaces" YANG module [RFC8343], and the
"ietf-lime-time-types" YANG module [RFC8532].

The YANG data model in this document conforms to the Network
Management Datastore Architecture (NMDA) defined in [RFC8342].

3.2. Pre-allocated Tracing Profile

To ensure visibility into the entire path that a packet takes within
an IOAM domain, the IOAM tracing data is expected to be collected at
every node that a packet traverses. The Pre-allocated Trace-Option
will create pre-allocated space for each node to populate its
information. The "preallocated-tracing-profile" parameter contains
the detailed information for the pre-allocated tracing data. This
information includes:

node-action: indicates the operation (e.g., encapsulate the IOAM
header, transit the IOAM data, or decapsulate the IOAM header)
applied to the dedicated flow.

use-namespace: indicates the namespace used for the trace types.

trace-type: indicates the per-hop data to be captured by IOAM-
enabled nodes and included in the node data list.

max-length: specifies the maximum length of the node data list in
octets. "max-length" is only defined at the encapsulation node.

+--rw preallocated-tracing-profile {preallocated-trace}?
+--rw node-action? ioam-node-action
+--rw trace-types
| +--rw use-namespace? ioam-namespace
| +--rw trace-type* ioam-trace-type
+--rw max-length? uint32

3.3. Incremental Tracing Profile

The Incremental Trace-Option contains a variable-length list of node
data fields, where each node allocates and pushes its node data
immediately following the option header. The "incremental-tracing-
profile" parameter contains the detailed information for the
incremental tracing data. This information is the same as that for
the Pre-allocated Tracing Profile; see Section 3.2.

+--rw incremental-tracing-profile {incremental-trace}?
+--rw node-action? ioam-node-action
+--rw trace-types
| +--rw use-namespace? ioam-namespace
| +--rw trace-type* ioam-trace-type
+--rw max-length? uint32

3.4. Direct Export Profile

The Direct Export Option is used as a trigger for IOAM data to be
directly exported or locally aggregated without being pushed into in-
flight data packets. The "direct-export-profile" parameter contains
the detailed information for the direct export data. This
information is the same as that for the Pre-allocated Tracing Profile
(Section 3.2), but with two more optional variables:

flow-id: used to correlate the exported data of the same flow from
multiple nodes and from multiple packets.

enable-sequence-number: indicates whether the sequence number is
used in the Direct Export Option.

+--rw direct-export-profile {direct-export}?
+--rw node-action? ioam-node-action
+--rw trace-types
| +--rw use-namespace? ioam-namespace
| +--rw trace-type* ioam-trace-type
+--rw flow-id? uint32
+--rw enable-sequence-number? boolean

3.5. Proof of Transit Profile

The IOAM proof of transit data is used to support the path or service
function chain verification use cases. The "pot-profile" parameter
is intended to contain the detailed information for the proof of
transit data. The "use-namespace" parameter indicates the namespace
used for the POT types. The "pot-type" parameter indicates a
particular POT variant that specifies the POT data that is included.
There may be several POT types, each having different configuration
data. To align with [RFC9197], this document only defines IOAM POT
type 0. Users need to augment this module for the configuration of a
specific POT type.

+--rw pot-profile {proof-of-transit}?
+--rw use-namespace? ioam-namespace
+--rw pot-type? ioam-pot-type

3.6. Edge-to-Edge Profile

The IOAM Edge-to-Edge Option is used to carry data that is added by
the IOAM encapsulating node and interpreted by the IOAM decapsulating
node. The "e2e-profile" parameter contains the detailed information
for the edge-to-edge data. This information includes:

node-action: the same semantic as that provided in Section 3.2.

use-namespace: indicates the namespace used for the edge-to-edge
types.

e2e-type: indicates data to be carried from the ingress IOAM node to
the egress IOAM node.

+--rw e2e-profile {edge-to-edge}?
+--rw node-action? ioam-node-action
+--rw e2e-types
+--rw use-namespace? ioam-namespace
+--rw e2e-type* ioam-e2e-type

4. IOAM YANG Module

The "ietf-ioam" module defined in this document imports typedefs from
[RFC8519], [RFC8343], and [RFC8532]. This document also references
[RFC9197], [RFC9326], [RFC9486], and [RFC9452].

<CODE BEGINS> file "[email protected]"
module ietf-ioam {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-ioam";
prefix ioam;

import ietf-access-control-list {
prefix acl;
reference
"RFC 8519: YANG Data Model for Network Access Control
Lists (ACLs)";
}
import ietf-interfaces {
prefix if;
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-lime-time-types {
prefix lime;
reference
"RFC 8532: Generic YANG Data Model for the Management of
Operations, Administration, and Maintenance (OAM) Protocols
That Use Connectionless Communications";
}

organization
"IETF IPPM (IP Performance Measurement) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/ippm>
WG List: <mailto:[email protected]>
Editor: Tianran Zhou
<mailto:[email protected]>
Author: Jim Guichard
<mailto:[email protected]>
Author: Frank Brockners
<mailto:[email protected]>
Author: Srihari Raghavan
<mailto:[email protected]>";
description
"This YANG module specifies a vendor-independent data model
for In Situ Operations, Administration, and Maintenance
(IOAM).

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) 2024 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 Revised 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 9617; see the
RFC itself for full legal notices.";

revision 2024-08-27 {
description
"Initial revision.";
reference
"RFC 9617: A YANG Data Model for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

/*
* FEATURES
*/

feature incremental-trace {
description
"This feature indicates that the Incremental Trace-Option is
supported.";
reference
"RFC 9197: Data Fields for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

feature preallocated-trace {
description
"This feature indicates that the Pre-allocated Trace-Option
is supported.";
reference
"RFC 9197: Data Fields for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

feature direct-export {
description
"This feature indicates that the Direct Export Option is
supported.";
reference
"RFC 9326: In Situ Operations, Administration, and
Maintenance (IOAM) Direct Exporting";
}

feature proof-of-transit {
description
"This feature indicates that the Proof of Transit Option is
supported.";
reference
"RFC 9197: Data Fields for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

feature edge-to-edge {
description
"This feature indicates that the Edge-to-Edge Option is
supported.";
reference
"RFC 9197: Data Fields for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

/*
* IDENTITIES
*/

identity filter {
description
"Base identity to represent a filter. A filter is used to
specify the flow to apply the IOAM profile.";
}

identity acl-filter {
base filter;
description
"Apply Access Control List (ACL) rules to specify the
flow.";
}

identity protocol {
description
"Base identity to represent the carrier protocol. It is
used to indicate in what layer and protocol the IOAM data
is embedded.";
}

identity ipv6 {
base protocol;
description
"The described IOAM data is embedded in IPv6.";
reference
"RFC 9486: IPv6 Options for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

identity nsh {
base protocol;
description
"The described IOAM data is embedded in the Network Service
Header (NSH).";
reference
"RFC 9452: Network Service Header (NSH) Encapsulation for
In Situ OAM (IOAM) Data";
}

identity node-action {
description
"Base identity to represent the node actions. It is used to
indicate what action the node will take.";
}

identity action-encapsulate {
base node-action;
description
"This identity indicates that the node is used to
encapsulate the IOAM packet.";
}

identity action-decapsulate {
base node-action;
description
"This identity indicates that the node is used to
decapsulate the IOAM packet.";
}

identity action-transit {
base node-action;
description
"This identity indicates that the node is used to transit
the IOAM packet.";
}

identity trace-type {
description
"Base identity to represent trace types.";
}

identity trace-hop-lim-node-id {
base trace-type;
description
"This identity indicates the presence of 'Hop_Lim' and
'node_id' in the node data.";
reference
"RFC 9197: Data Fields for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

identity trace-if-id {
base trace-type;
description
"This identity indicates the presence of 'ingress_if_id' and
'egress_if_id' (short format) in the node data.";
reference
"RFC 9197: Data Fields for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

identity trace-timestamp-seconds {
base trace-type;
description
"This identity indicates the presence of timestamp seconds
in the node data.";
}

identity trace-timestamp-fraction {
base trace-type;
description
"This identity indicates the presence of a timestamp
fraction in the node data.";
}

identity trace-transit-delay {
base trace-type;
description
"This identity indicates the presence of transit delay in
the node data.";
}

identity trace-namespace-data {
base trace-type;
description
"This identity indicates the presence of namespace-specific
data (short format) in the node data.";
}

identity trace-queue-depth {
base trace-type;
description
"This identity indicates the presence of queue depth in the
node data.";
}

identity trace-checksum-complement {
base trace-type;
description
"This identity indicates the presence of the Checksum
Complement in the node data.";
reference
"RFC 9197: Data Fields for In Situ Operations,
Administration, and Maintenance (IOAM)";
}

identity trace-hop-lim-node-id-wide {
base trace-type;
description
"This identity indicates the presence of 'Hop_Lim' and
'node_id' (wide format) in the node data.";
}

identity trace-if-id-wide {
base trace-type;
description
"This identity indicates the presence of 'ingress_if_id' and
'egress_if_id' (wide format) in the node data.";
}

identity trace-namespace-data-wide {
base trace-type;
description
"This identity indicates the presence of
IOAM-namespace-specific data (wide format) in the
node data.";
}

identity trace-buffer-occupancy {
base trace-type;
description
"This identity indicates the presence of buffer occupancy
in the node data.";
}

identity trace-opaque-state-snapshot {
base trace-type;
description
"This identity indicates the presence of the variable-length
Opaque State Snapshot field.";
}

identity pot-type {
description
"Base identity to represent Proof of Transit (POT) types.";
}

identity pot-type-0 {
base pot-type;
description
"The IOAM field value for the POT type is 0, and POT data is
a 16-octet field to carry data associated with POT
procedures.";
}

identity e2e-type {
description
"Base identity to represent edge-to-edge types.";
}

identity e2e-seq-num-64 {
base e2e-type;
description
"This identity indicates the presence of a 64-bit
sequence number.";
}

identity e2e-seq-num-32 {
base e2e-type;
description
"This identity indicates the presence of a 32-bit
sequence number.";
}

identity e2e-timestamp-seconds {
base e2e-type;
description
"This identity indicates the presence of timestamp seconds
representing the time at which the packet entered the
IOAM domain.";
}

identity e2e-timestamp-fraction {
base e2e-type;
description
"This identity indicates the presence of a timestamp
fraction representing the time at which the packet entered
the IOAM domain.";
}

identity namespace {
description
"Base identity to represent the Namespace-ID.";
}

identity default-namespace {
base namespace;
description
"The Namespace-ID value of 0x0000 is defined as the
Default-Namespace-ID and MUST be known to all the nodes
implementing IOAM.";
}

/*
* TYPE DEFINITIONS
*/

typedef ioam-filter-type {
type identityref {
base filter;
}
description
"This type specifies a known type of filter.";
}

typedef ioam-protocol-type {
type identityref {
base protocol;
}
description
"This type specifies a known type of carrier protocol for
the IOAM data.";
}

typedef ioam-node-action {
type identityref {
base node-action;
}
description
"This type specifies a known type of node action.";
}

typedef ioam-trace-type {
type identityref {
base trace-type;
}
description
"This type specifies a known trace type.";
}

typedef ioam-pot-type {
type identityref {
base pot-type;
}
description
"This type specifies a known POT type.";
}

typedef ioam-e2e-type {
type identityref {
base e2e-type;
}
description
"This type specifies a known edge-to-edge type.";
}

typedef ioam-namespace {
type identityref {
base namespace;
}
description
"This type specifies the supported namespace.";
}

/*
* GROUP DEFINITIONS
*/

grouping ioam-filter {
description
"A grouping for IOAM filter definitions.";
leaf filter-type {
type ioam-filter-type;
description
"Filter type.";
}
leaf ace-name {
when "derived-from-or-self(../filter-type, 'ioam:acl-filter')";
type leafref {
path "/acl:acls/acl:acl/acl:aces/acl:ace/acl:name";
}
description
"The Access Control Entry name is used to refer to an ACL
specification.";
}
}

grouping encap-tracing {
description
"A grouping for the generic configuration for the
tracing profile.";
container trace-types {
description
"This container provides the list of trace types for
encapsulation.";
leaf use-namespace {
type ioam-namespace;
default "default-namespace";
description
"This object indicates the namespace used for
encapsulation.";
}
leaf-list trace-type {
type ioam-trace-type;
description
"The trace type is only defined at the encapsulation
node.";
}
}
leaf max-length {
when "derived-from-or-self(../node-action,
'ioam:action-encapsulate')";
type uint32;
units "bytes";
description
"This field specifies the maximum length of the node data
list in octets. 'max-length' is only defined at the
encapsulation node.";
}
}

grouping ioam-incremental-tracing-profile {
description
"A grouping for the Incremental Tracing Profile.";
leaf node-action {
type ioam-node-action;
default "action-transit";
description
"This object indicates the action the node needs to
take, e.g., encapsulation.";
}
uses encap-tracing {
when "derived-from-or-self(node-action,
'ioam:action-encapsulate')";
}
}

grouping ioam-preallocated-tracing-profile {
description
"A grouping for the Pre-allocated Tracing Profile.";
leaf node-action {
type ioam-node-action;
default "action-transit";
description
"This object indicates the action the node needs to
take, e.g., encapsulation.";
}
uses encap-tracing {
when "derived-from-or-self(node-action,
'ioam:action-encapsulate')";
}
}

grouping ioam-direct-export-profile {
description
"A grouping for the Direct Export Profile.";
leaf node-action {
type ioam-node-action;
default "action-transit";
description
"This object indicates the action the node needs to
take, e.g., encapsulation.";
}
uses encap-tracing {
when "derived-from-or-self(node-action,
'ioam:action-encapsulate')";
}
leaf flow-id {
when "derived-from-or-self(../node-action,
'ioam:action-encapsulate')";
type uint32;
description
"A 32-bit flow identifier. The field is set at the
encapsulating node. The Flow ID can be uniformly
assigned by a central controller or algorithmically
generated by the encapsulating node. The latter approach
cannot guarantee the uniqueness of the Flow ID, yet the
probability of conflict is small due to the large Flow ID
space. 'flow-id' is used to correlate the exported data
of the same flow from multiple nodes and from multiple
packets.";
}
leaf enable-sequence-number {
when "derived-from-or-self(../node-action,
'ioam:action-encapsulate')";
type boolean;
default "false";
description
"This boolean value indicates whether the sequence number
is used in the Direct Export Option's 32-bit flow
identifier. If this value is set to 'true', the sequence
number is used. It is turned off by default.";
}
}

grouping ioam-e2e-profile {
description
"A grouping for the Edge-to-Edge Profile.";
leaf node-action {
type ioam-node-action;
default "action-transit";
description
"This object indicates the action the node needs to
take, e.g., encapsulation.";
}
container e2e-types {
when "derived-from-or-self(../node-action,
'ioam:action-encapsulate')";
description
"This container provides the list of edge-to-edge types
for encapsulation.";
leaf use-namespace {
type ioam-namespace;
default "default-namespace";
description
"This object indicates the namespace used for
encapsulation.";
}
leaf-list e2e-type {
type ioam-e2e-type;
description
"The edge-to-edge type is only defined at the
encapsulation node.";
}
}
}

grouping ioam-admin-config {
description
"IOAM top-level administrative configuration.";
leaf enabled {
type boolean;
default "false";
description
"This object is used to control the availability of
configuration. It MUST be set to 'true' before anything
in the /ioam/profiles/profile subtree can be edited.
If 'false', any configuration in place is not used.";
}
}

/*
* DATA NODES
*/

container ioam {
description
"IOAM top-level container.";
container info {
config false;
description
"Describes information, such as units or timestamp format,
that assists monitoring systems in the interpretation of
the IOAM data.";
leaf timestamp-type {
type identityref {
base lime:timestamp-type;
}
description
"Type of timestamp, such as Truncated PTP (Precision
Time Protocol) or NTP.";
}
list available-interface {
key "if-name";
description
"A list of available interfaces that support IOAM.";
leaf if-name {
type if:interface-ref;
description
"This is a reference to the interface name.";
}
}
}
container admin-config {
description
"Contains all the administrative configurations related to
the IOAM functionalities and all the IOAM profiles.";
uses ioam-admin-config;
}
container profiles {
description
"Contains a list of IOAM profiles.";
list profile {
key "profile-name";
description
"A list of IOAM profiles that are configured on the
node. There is no mandatory type of profile (e.g.,
'incremental-trace', 'preallocated-trace') in the list.
But at least one profile should be added.";
leaf profile-name {
type string {
length "1..300";
}
description
"Unique identifier for each IOAM profile.";
}
container filter {
uses ioam-filter;
description
"The filter that is used to indicate the flow to apply
IOAM.";
}
leaf protocol-type {
type ioam-protocol-type;
description
"This object is used to indicate the carrier protocol
where IOAM is applied.";
}
container incremental-tracing-profile {
if-feature "incremental-trace";
presence "Enables the Incremental Trace-Option.";
description
"This container describes the profile for the
Incremental Trace-Option.";
uses ioam-incremental-tracing-profile;
}
container preallocated-tracing-profile {
if-feature "preallocated-trace";
presence "Enables the Pre-allocated Trace-Option.";
description
"This container describes the profile for the
Pre-allocated Trace-Option.";
uses ioam-preallocated-tracing-profile;
}
container direct-export-profile {
if-feature "direct-export";
presence "Enables the Direct Export Option.";
description
"This container describes the profile for the
Direct Export Option.";
uses ioam-direct-export-profile;
}
container pot-profile {
if-feature "proof-of-transit";
presence "Enables the Proof of Transit Option.";
description
"This container describes the profile for the
Proof of Transit Option.";
leaf use-namespace {
type ioam-namespace;
default "default-namespace";
description
"This object indicates the namespace used for the
POT types.";
}
leaf pot-type {
type ioam-pot-type;
description
"The type of a particular POT variant that specifies
the POT data that is included.";
}
}
container e2e-profile {
if-feature "edge-to-edge";
presence "Enables the Edge-to-Edge Option.";
description
"This container describes the profile for the
Edge-to-Edge Option.";
uses ioam-e2e-profile;
}
}
}
}
}
<CODE ENDS>

5. 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.

There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
to these data nodes without proper protection can have a negative
effect on network operations. These are the subtrees and data nodes
and their sensitivity/vulnerability:

/ioam/admin-config: The items in the "admin-config" container above
include the top-level administrative configurations related to the
IOAM functionalities and all the IOAM profiles. Unexpected
changes to these items could lead to disruption of IOAM functions
and/or misbehaving IOAM profiles.

/ioam/profiles/profile: The entries in the "profile" list above
include the whole IOAM profile configurations. Unexpected changes
to these entries could lead to incorrect IOAM behavior for the
corresponding flows. Consequently, such changes would impact
performance monitoring, data analytics, and associated
interactions with network services.

Some of the readable data nodes in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control read access (e.g., via get, get-config, or
notification) to these data nodes. These are the subtrees and data
nodes and their sensitivity/vulnerability:

/ioam/profiles/profile: The information contained in this subtree
might reveal information about the services deployed for
customers. For instance, a customer might be given access to
monitor the status of their services. In this scenario, the
customer's access should be restricted to nodes representing their
services so as not to divulge information about the underlying
network structure or services.

6. IANA Considerations

IANA has registered the following URI in the "IETF XML Registry"
[RFC3688]:

URI: urn:ietf:params:xml:ns:yang:ietf-ioam
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.

IANA has registered the following YANG module in the "YANG Module
Names" registry [RFC6020]:

Name: ietf-ioam
Namespace: urn:ietf:params:xml:ns:yang:ietf-ioam
Prefix: ioam
Reference: RFC 9617

7. Normative 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>.

[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.

[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>.

[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>.

[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>.

[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>.

[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.

[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>.

[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>.

[RFC8519] Jethanandani, M., Agarwal, S., Huang, L., and D. Blair,
"YANG Data Model for Network Access Control Lists (ACLs)",
RFC 8519, DOI 10.17487/RFC8519, March 2019,
<https://www.rfc-editor.org/info/rfc8519>.

[RFC8532] Kumar, D., Wang, Z., Wu, Q., Ed., Rahman, R., and S.
Raghavan, "Generic YANG Data Model for the Management of
Operations, Administration, and Maintenance (OAM)
Protocols That Use Connectionless Communications",
RFC 8532, DOI 10.17487/RFC8532, April 2019,
<https://www.rfc-editor.org/info/rfc8532>.

[RFC9197] Brockners, F., Ed., Bhandari, S., Ed., and T. Mizrahi,
Ed., "Data Fields for In Situ Operations, Administration,
and Maintenance (IOAM)", RFC 9197, DOI 10.17487/RFC9197,
May 2022, <https://www.rfc-editor.org/info/rfc9197>.

[RFC9326] Song, H., Gafni, B., Brockners, F., Bhandari, S., and T.
Mizrahi, "In Situ Operations, Administration, and
Maintenance (IOAM) Direct Exporting", RFC 9326,
DOI 10.17487/RFC9326, November 2022,
<https://www.rfc-editor.org/info/rfc9326>.

[RFC9452] Brockners, F., Ed. and S. Bhandari, Ed., "Network Service
Header (NSH) Encapsulation for In Situ OAM (IOAM) Data",
RFC 9452, DOI 10.17487/RFC9452, August 2023,
<https://www.rfc-editor.org/info/rfc9452>.

[RFC9486] Bhandari, S., Ed. and F. Brockners, Ed., "IPv6 Options for
In Situ Operations, Administration, and Maintenance
(IOAM)", RFC 9486, DOI 10.17487/RFC9486, September 2023,
<https://www.rfc-editor.org/info/rfc9486>.

[W3C.REC-xml11-20060816]
Bray, T., Paoli, J., Sperberg-McQueen, C. M., Maler, E.,
Yergeau, F., and J. Cowan, "Extensible Markup Language
(XML) 1.1 (Second Edition)", W3C Consortium Recommendation
REC-xml11-20060816, August 2006,
<https://www.w3.org/TR/2006/REC-xml11-20060816>.

Appendix A. An Example of the Incremental Tracing Profile

An XML example (per [W3C.REC-xml11-20060816]) of the Incremental
Tracing Profile is depicted in the following figure. This
configuration is received by an IOAM ingress node. This node
encapsulates the IOAM data in the IPv6 Hop-by-Hop option header. The
trace type indicates that each on-path node needs to capture the
transit delay and add the data to the IOAM node data list. The
incremental tracing data space is variable; however, the node data
list must not exceed 512 bytes.

<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
message-id="101">
<edit-config>
<target>
<candidate/>
</target>
<config>
<ioam xmlns="urn:ietf:params:xml:ns:yang:ietf-ioam">
<admin-config>
<enabled>true</enabled>
</admin-config>
<profiles>
<profile>
<profile-name>ietf-test-profile</profile-name>
<protocol-type>ipv6</protocol-type>
<incremental-tracing-profile>
<node-action>action-encapsulate</node-action>
<trace-types>
<use-namespace>default-namespace</use-namespace>
<trace-type>trace-transit-delay</trace-type>
</trace-types>
<max-length>512</max-length>
</incremental-tracing-profile>
</profile>
</profiles>
</ioam>
</config>
</edit-config>
</rpc>

Appendix B. An Example of the Pre-allocated Tracing Profile

An example of the Pre-allocated Tracing Profile is depicted in the
following figure. This configuration is received by an IOAM ingress
node. This node first identifies the target flow by using the ACL
parameter "test-acl" and then encapsulates the IOAM data in the NSH.
The trace type indicates that each on-path node needs to capture the
namespace-specific data in short format and add the data to the IOAM
node data list. This node pre-allocates the node data list in the
packet with 512 bytes.

<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
message-id="101">
<edit-config>
<target>
<candidate/>
</target>
<config>
<ioam xmlns="urn:ietf:params:xml:ns:yang:ietf-ioam">
<admin-config>
<enabled>true</enabled>
</admin-config>
<profiles>
<profile>
<profile-name>ietf-test-profile</profile-name>
<filter>
<filter-type>acl-filter</filter-type>
<ace-name>test-acl</ace-name>
</filter>
<protocol-type>nsh</protocol-type>
<preallocated-tracing-profile>
<node-action>action-encapsulate</node-action>
<trace-types>
<use-namespace>default-namespace</use-namespace>
<trace-type>trace-namespace-data</trace-type>
</trace-types>
<max-length>512</max-length>
</preallocated-tracing-profile>
</profile>
</profiles>
</ioam>
</config>
</edit-config>
</rpc>

Appendix C. An Example of the Direct Export Profile

An example of the Direct Export Profile is depicted in the following
figure. This configuration is received by an IOAM egress node. This
node detects the IOAM Direct Export Option in the IPv6 extension
header and removes the option to clean all the IOAM data.

<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
message-id="101">
<edit-config>
<target>
<candidate/>
</target>
<config>
<ioam xmlns="urn:ietf:params:xml:ns:yang:ietf-ioam">
<admin-config>
<enabled>true</enabled>
</admin-config>
<profiles>
<profile>
<profile-name>ietf-test-profile</profile-name>
<protocol-type>ipv6</protocol-type>
<direct-export-profile>
<node-action>action-decapsulate</node-action>
</direct-export-profile>
</profile>
</profiles>
</ioam>
</config>
</edit-config>
</rpc>

Appendix D. An Example of the Proof of Transit Profile

A simple example of the Proof of Transit Profile is depicted in the
following figure. This configuration indicates the node to apply POT
type 0 with IPv6 encapsulation.

<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
message-id="101">
<edit-config>
<target>
<candidate/>
</target>
<config>
<ioam xmlns="urn:ietf:params:xml:ns:yang:ietf-ioam">
<admin-config>
<enabled>true</enabled>
</admin-config>
<profiles>
<profile>
<profile-name>ietf-test-profile</profile-name>
<protocol-type>ipv6</protocol-type>
<pot-profile>
<pot-type>pot-type-0</pot-type>
</pot-profile>
</profile>
</profiles>
</ioam>
</config>
</edit-config>
</rpc>

Appendix E. An Example of the Edge-to-Edge Profile

An example of the Edge-to-Edge Profile is depicted in the following
figure. This configuration is received by an IOAM egress node. This
node detects the IOAM Edge-to-Edge Option in the IPv6 extension
header and removes the option to clean all the IOAM data. As the
IOAM egress node, it may collect the edge-to-edge data and deliver it
to the data-exporting process.

<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
message-id="101">
<edit-config>
<target>
<candidate/>
</target>
<config>
<ioam xmlns="urn:ietf:params:xml:ns:yang:ietf-ioam">
<admin-config>
<enabled>true</enabled>
</admin-config>
<profiles>
<profile>
<profile-name>ietf-test-profile</profile-name>
<protocol-type>ipv6</protocol-type>
<e2e-profile>
<node-action>action-decapsulate</node-action>
</e2e-profile>
</profile>
</profiles>
</ioam>
</config>
</edit-config>
</rpc>

Acknowledgements

For their valuable comments, discussions, and feedback, we wish to
acknowledge Greg Mirsky, Reshad Rahman, Tom Petch, Mickey Spiegel,
Thomas Graf, Alex Huang Feng, and Justin Iurman.

Authors' Addresses

Tianran Zhou (editor)
Huawei
156 Beiqing Rd.
Beijing
100095
China
Email: [email protected]

Jim Guichard
Futurewei
United States of America
Email: [email protected]

Frank Brockners
Cisco Systems
Hansaallee 249, 3rd Floor
40549 Düsseldorf, Nordrhein-Westfalen
Germany
Email: [email protected]

Srihari Raghavan
Cisco Systems
Tril Infopark Sez, Ramanujan IT City
Neville Block, 2nd floor, Old Mahabalipuram Road
Chennai 600113
Tamil Nadu
India
Email: [email protected]