Information and Data Models for Packet Discard Reporting
draft-ietf-opsawg-discardmodel-14
| Document | Type | Active Internet-Draft (opsawg WG) | |
|---|---|---|---|
| Authors | John Evans , Oleksandr Pylypenko , Jeffrey Haas , Aviran Kadosh , Mohamed Boucadair | ||
| Last updated | 2026-07-09 (Latest revision 2026-06-24) | ||
| Replaces | draft-opsawg-evans-discardmodel | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | Proposed Standard | ||
| Formats | |||
| Yang Validation | 0 errors, 0 warnings | ||
| Reviews |
INTDIR Telechat review
by Carlos Pignataro
Ready w/issues
YANGDOCTORS Early review
(of
-10)
by Ladislav Lhotka
Ready w/issues
INTDIR Early review
(of
-09)
by Satoru Matsushima
Ready w/nits
YANGDOCTORS Early review
(of
-03)
by Ladislav Lhotka
Ready w/issues
|
||
| Additional resources |
GitHub Repository
Related Implementations Mailing list discussion |
||
| Stream | WG state | Submitted to IESG for Publication | |
| Associated WG milestone |
|
||
| Document shepherd | Diego Lopez | ||
| Shepherd write-up | Show Last changed 2026-05-12 | ||
| IESG | IESG state | IESG Evaluation::Revised I-D Needed | |
| Action Holders | |||
| Consensus boilerplate | Yes | ||
| Telechat date |
(None)
Has 4 DISCUSSes. Needs 3 more YES or NO OBJECTION positions to pass. |
||
| Responsible AD | Mahesh Jethanandani | ||
| Send notices to | diego.r.lopez@telefonica.com | ||
| IANA | IANA review state | IANA OK - Actions Needed | |
| IANA expert review state | Expert Reviews OK |
draft-ietf-opsawg-discardmodel-14
Operations and Management Area Working Group J. Evans, Ed.
Internet-Draft Amazon
Intended status: Standards Track O. Pylypenko, Ed.
Expires: 26 December 2026 Nvidia
J. Haas
Juniper Networks
A. Kadosh
Cisco Systems, Inc.
M. Boucadair, Ed.
Orange
24 June 2026
Information and Data Models for Packet Discard Reporting
draft-ietf-opsawg-discardmodel-14
Abstract
This document defines an Information Model and specifies a
corresponding YANG data model for packet discard reporting. The
Information Model provides an implementation-independent framework
for classifying packet loss - both intended (e.g., due to policy) and
unintended (e.g., due to congestion or errors) - to enable automated
network mitigation of unintended packet loss. The YANG data model
specifies an implementation of this Information Model for network
elements with a focus on the interface, device, and control-plane
discards.
About This Document
This note is to be removed before publishing as an RFC.
The latest revision of this draft can be found at https://o-
pylypenko.github.io/draft-ietf-opsawg-discardmodel/draft-ietf-opsawg-
discardmodel.html. Status information for this document may be found
at https://datatracker.ietf.org/doc/draft-ietf-opsawg-discardmodel/.
Discussion of this document takes place on the Operations and
Management Area Working Group mailing list (mailto:opsawg@ietf.org),
which is archived at https://mailarchive.ietf.org/arch/browse/
opsawg/. Subscribe at https://www.ietf.org/mailman/listinfo/opsawg/.
Source for this draft and an issue tracker can be found at
https://github.com/o-pylypenko/draft-ietf-opsawg-discardmodel.
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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 26 December 2026.
Copyright Notice
Copyright (c) 2026 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 . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Editorial Note (To be removed by the RFC Editor) . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 5
4. Information Model (IM) . . . . . . . . . . . . . . . . . . . 6
4.1. Structure . . . . . . . . . . . . . . . . . . . . . . . . 7
4.2. Subtype Definitions . . . . . . . . . . . . . . . . . . . 10
4.3. "ietf-packet-discard-reporting-common" YANG Module . . . 11
4.4. "ietf-packet-discard-reporting-sx" YANG Module . . . . . 25
5. Data Model (DM) . . . . . . . . . . . . . . . . . . . . . . . 27
5.1. Structure . . . . . . . . . . . . . . . . . . . . . . . . 28
5.2. Implementation Requirements . . . . . . . . . . . . . . . 29
5.3. Usage Examples . . . . . . . . . . . . . . . . . . . . . 31
5.4. "ietf-packet-discard-reporting" YANG Module . . . . . . . 32
6. Operational Considerations . . . . . . . . . . . . . . . . . 36
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6.1. Determining Intent for Policy . . . . . . . . . . . . . . 37
6.2. Deployment Experience . . . . . . . . . . . . . . . . . . 37
6.3. Anchoring Flow Structure . . . . . . . . . . . . . . . . 38
7. Implementation Status . . . . . . . . . . . . . . . . . . . . 38
7.1. Information Model Implementations . . . . . . . . . . . . 39
7.2. Data Model Implementations . . . . . . . . . . . . . . . 39
8. Security Considerations . . . . . . . . . . . . . . . . . . . 39
8.1. Information Model . . . . . . . . . . . . . . . . . . . . 39
8.2. Data Model . . . . . . . . . . . . . . . . . . . . . . . 40
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 41
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 41
10.1. Normative References . . . . . . . . . . . . . . . . . . 41
10.2. Informative References . . . . . . . . . . . . . . . . . 43
Appendix A. Where Do Packets Get Dropped? . . . . . . . . . . . 45
Appendix B. Example Signal-to-mitigation Action Mapping . . . . 46
Appendix C. Full Information Model Tree . . . . . . . . . . . . 48
Appendix D. Full Data Model Tree . . . . . . . . . . . . . . . . 55
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 59
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 60
1. Introduction
The primary function of a network is to transport and deliver packets
according to service level objectives. For network operators,
understanding both where and why packet loss occurs within a network
is essential for effective operation. Device-reported packet loss
provides the most direct signal for identifying service impact.
While certain types of packet loss, such as policy-based discards,
are intentional and part of normal network operation, unintended
packet loss can impact customer services. To automate network
operations, operators must be able to detect customer-impacting
packet loss, determine its root cause, and apply appropriate
mitigation actions. Precise classification of packet loss is thus
crucial to ensure that anomalous packet loss is easily detected and
that the right action is taken to mitigate the impact. Taking the
wrong action can make problems worse; for example, removing a
congested device from service can exacerbate congestion by
redirecting traffic to other already congested links or devices.
Existing metrics for reporting packet loss, such as ifInDiscards,
ifOutDiscards, ifInErrors, and ifOutErrors defined in "The Interfaces
Group MIB" [RFC2863] and "A YANG Data Model for Interface Management"
[RFC8343], are insufficient for automating network operations.
First, they lack precision; for instance, ifInDiscards aggregates all
discarded inbound packets without specifying the cause, making it
challenging to distinguish between intended and unintended discards.
Second, these definitions are ambiguous, leading to inconsistent
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vendor implementations. For example, in some implementations
ifInErrors accounts only for errored packets that are dropped, while
in others, it includes all errored packets, whether they are dropped
or not. Many implementations support more discard metrics than
these, however, they have been inconsistently implemented due to the
lack of a standardised classification scheme and clear semantics for
packet loss reporting. For example, [RFC7270] provides support for
reporting discards per flow in IP Flow Information Export (IPFIX)
[RFC7011] using the forwardingStatus IPFIX Information Element,
however, the defined drop reason codes also lack sufficient clarity
to facilitate automated root cause analysis and impact mitigation
(e.g., the "For us" reason code).
This document defines an Information Model (IM) and specifies a
corresponding YANG Data Model (DM) for packet loss reporting to
address the above issues. The IM provides precise classification of
packet loss to enable accurate automated mitigation. The DM
specifies a YANG implementation of this IM for network elements,
while maintaining consistency through clear semantics.
The scope of this document is limited to reporting packet loss at
Layer 3 and frames discarded at Layer 2. This document considers
only the signals that may trigger automated mitigation actions and
not how the actions are defined or executed. Such considerations are
deployment-specific.
Section 3 describes the problem space and requirements. Section 4
defines the IM and its classification scheme. Section 5 specifies
the corresponding YANG data model and implementation requirements
together with a set of usage examples, and the complete YANG module
definition. Appendices A and B provide additional context and
implementation guidance.
1.1. Editorial Note (To be removed by the RFC Editor)
Note to the RFC Editor: This section is to be removed prior to
publication.
This document contains placeholder values that need to be replaced
with finalized values at the time of publication. This note
summarizes all of the substitutions that are needed.
Please apply the following replacements:
* XXXX --> the assigned RFC number for this I-D
* 2026-03-03 --> the actual date of the publication of this document
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2. 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.
Tree diagrams used in this document follow the notation defined in
[RFC8340].
This document makes use of the following terms:
Packet discard: It accounts for any instance where a packet is
dropped by a device, regardless of whether the discard was
intentional or unintentional.
Intended packet discards (Intended discards, for short): Are packets
dropped due to deliberate network policies or configurations
designed to enforce security or Quality of Service (QoS). For
example, packets dropped because they match an Access Control List
(ACL) denying certain traffic types.
Unintended packet discards (Unintended discards, for short): Are
packets that were dropped, which the network operator otherwise
intended to deliver, i.e., which indicates an error state. There
are many possible reasons for unintended packet loss, including:
erroring links may corrupt packets in transit; incorrect routing
tables may result in packets being dropped because they do not
match a valid route; configuration errors may result in a valid
packet incorrectly matching an ACL and being dropped.
3. Problem Statement
The fundamental problem for network operators is how to automatically
detect when and where unintended packet loss is occurring and
determine the appropriate action to mitigate it. For any network,
there are a small set of potential actions that can be taken to
mitigate customer impact when unintended packet loss is detected, for
example:
1. Take a problematic device, link, or set of devices and/or links
out of service.
2. Return a device, link, or set of devices and/or links back into
service.
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3. Move traffic to other links or devices to alleviate congestion or
avoid problematic paths.
4. Roll back a recent change to a device that might have caused the
problem.
5. Escalate to a network operator as a last resort when automated
mitigation is not possible.
The ability to select the appropriate mitigation action depends on
four key features of packet loss:
FEATURE-DISCARD-SCOPE: Determines which devices, interfaces, and/or
flows are impacted. This also needs to cover control plane
discards.
FEATURE-DISCARD-RATE: The rate and/or magnitude of the discards,
indicating the severity and urgency of the problem. Rate may be
expressed using absolute (e.g., packets per second (pps)) or
relative (e.g., percent) values.
FEATURE-DISCARD-DURATION: The duration of the discards which helps
to distinguish transient from persistent issues.
FEATURE-DISCARD-CLASS: The type or class of discards, which is
crucial for selecting the appropriate type of mitigation.
Examples may be: error discards may require taking faulty
components out of service, no-buffer discards may require traffic
redistribution, or intended policy discards typically require no
action. Refer to Table 1 for more examples.
While most of FEATURE-DISCARD-SCOPE, FEATURE-DISCARD-RATE, and
FEATURE-DISCARD-DURATION are implicitly supported by the Interfaces
Group MIB [RFC2863] and the YANG Data Model for Interface Management
[RFC8343], FEATURE-DISCARD-CLASS requires a more detailed
classification scheme than they define. The IM provided in Section 4
defines such a classification scheme to enable automated mapping from
discard signals to appropriate mitigation actions (refer to
Appendix B for examples).
4. Information Model (IM)
The IM is defined using YANG [RFC7950], with Data Structure
Extensions [RFC8791], allowing the model to remain abstract and
decoupled from specific implementations in accordance with [RFC3444].
This abstraction supports different DM implementations, such as YANG
or IPFIX [RFC7011], while ensuring consistency across
implementations. Using YANG for the IM enables this abstraction,
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leverages the community's familiarity with its syntax, and ensures
lossless translation to the corresponding YANG data model, which is
defined in Section 5.
Design note: In order to ease reuse of the IM structure by DMs but
without requiring that these DMs to parse the "sx" structure
defined in [RFC8791], main reusable nodes are defined in a common
module (Section 4.3) while the main IM structure is defined in
Section 4.4.
4.1. Structure
The IM defines a hierarchical classification scheme for packet
discards, which captures where in a device the discards are accounted
(component), in which direction of traffic they were flowing
(direction), whether they were successfully processed or discarded
(type), what protocol layer they belong to (layer), and the specific
reason for any discards (subtypes). This structure enables both
high-level monitoring of total discards (i.e., aggregates) and more
detailed triage to map to mitigation actions.
The abstract structure of the IM is depicted in Figure 1. The full
YANG tree diagram of the IM is provided in Appendix C.
module: ietf-packet-discard-reporting-sx
structure packet-discard-reporting:
+-- control-plane {pdr-common:control-plane-stats}?
| +-- traffic* [direction]
| | ...
| +-- discards* [direction]
| ...
+-- interface* [name] {pdr-common:interface-stats}?
| +-- name string
| +-- traffic* [direction]
| | +-- direction identityref
| | +-- l2
| | | ...
| | +-- l3
| | | ...
| | +-- qos
| | ...
| +-- discards* [direction]
| +-- direction identityref
| +-- l2
| | ...
| +-- l3
| | ...
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| +-- errors
| | +-- l2
| | | ...
| | +-- l3
| | | ...
| | +-- internal
| | ...
| +-- policy
| | +-- l2
| | | ...
| | +-- l3
| | ...
| +-- no-buffer
| ...
+-- flow* [direction] {pdr-common:flow-reporting}?
| +-- direction identityref
| +-- traffic
| | +-- l2
| | | ...
| | +-- l3
| | | ...
| | +-- qos
| | ...
| +-- discards
| +-- l2
| | ...
| +-- l3
| | ...
| +-- errors
| | +-- l2
| | | ...
| | +-- l3
| | | ...
| | +-- internal
| | ...
| +-- policy
| | +-- l2
| | | ...
| | +-- l3
| | ...
| +-- no-buffer
| ...
+-- device {pdr-common:device-stats}?
+-- traffic
| +-- l2
| | ...
| +-- l3
| | ...
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| +-- qos
| ...
+-- discards
+-- l2
| ...
+-- l3
| ...
+-- errors
| +-- l2
| | ...
| +-- l3
| | ...
| +-- internal
| ...
+-- policy
| +-- l2
| | ...
| +-- l3
| ...
+-- no-buffer
...
Figure 1: Abstract IM Tree Structure
The discard reporting can be organized into several types: control
plane, interface, flow, and device. In order to allow for better
mapping to underlying DMs, the IM supports a set of "features" to
control the supported type.
A complete classification path follows the pattern:
component/direction/type/layer/subtype/sub-subtype/.../metric.
Appendix A illustrates where these discards typically occur in a
network device. The elements of the tree are defined as follows:
* Component:
- control-plane: discards of traffic to or from a device's
control plane.
- interface: discards of traffic to or from a specific network
interface.
- flow: discards of traffic associated with a specific traffic
flow.
- device: discards of traffic transiting the device.
* Direction:
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- ingress: counters for incoming packets or frames.
- egress: counters for outgoing packets or frames.
* Type:
- traffic: counters for successfully received or transmitted
packets or frames.
- discards: counters for packets or frames that were dropped.
* Layer:
- l2: Layer 2 traffic and discards. This covers both frame and
byte counts.
- l3: Layer 3 traffic and discards. This covers both packet and
byte counts.
The hierarchical structure allows for future extensions while
maintaining backward compatibility. New discard types can be added
as new branches without affecting existing implementations.
The corresponding YANG module is defined in Section 4.4.
4.2. Subtype Definitions
discards/policy/: These are intended discards, meaning packets
dropped due to a configured policy, including: ACLs, traffic
policers, unicast Reverse Path Forwarding (uRPF) checks,
Distributed Denial-of-Service (DDoS) protection rules, and
explicit null routes. In practice, ingress DDoS protection
policies are often realized using mechanisms such as ingress
filtering and uRPF ([RFC2827], [RFC3704], and [RFC8704]), remotely
triggered blackholing ([RFC3882], [RFC5635]), or BGP Flow
Specification–based filters ([RFC8955], [RFC8956], and [RFC9117]);
all such policy-driven discards are reported under this class.
discards/errors/: These are unintended discards due to errors in
processing packets or frames. There are multiple sub-classes:
* discards/errors/l2/rx/: These are frames discarded due to
errors in the received Layer 2 frame, including: Cyclic
Redundancy Check (CRC) errors, invalid Media Access Control
(MAC) addresses, invalid VLAN tags, frame size violations
and other malformed frame conditions.
* discards/errors/l3/rx/: These discards occur due to errors in
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the received packet, indicating an upstream problem rather
than an issue with the device dropping the errored packets,
including: header checksum errors, MTU exceeded, invalid
packet errors (i.e., incorrect version, incorrect header
length, invalid options, and other malformed packet
conditions).
* discards/errors/l3/ttl-expired: These discards occur due to
TTL (or Hop limit) expiry. These can occur, e.g., for the
following reasons: normal trace-route operations, end-system
TTL/Hop limit set too low, or routing loops in the network.
* discards/errors/l3/no-route/: These discards occur due to a
packet not matching any route in the routing table, e.g.,
which may be due to routing configuration errors or may be
transient discards during convergence.
* discards/errors/internal/: These discards occur due to
internal device issues, including: parity errors in device
memory or other internal hardware errors. Any errored
discards not explicitly assigned to other classes are also
accounted for here.
discards/no-buffer/: These are discards due to buffer exhaustion
(that is congestion related discards). These can be tail-drop
discards or due to an active queue management algorithm, such as
Random Early Detection (RED) [RED93] or Controlled Delay (CoDel)
[RFC8289].
An example of possible signal-to-mitigation action mapping is
provided in Appendix B.
4.3. "ietf-packet-discard-reporting-common" YANG Module
The "ietf-packet-discard-reporting-common" module imports "ietf-yang-
types" defined in [RFC9911].
<CODE BEGINS>
file "ietf-packet-discard-reporting-common@2026-03-03.yang"
module ietf-packet-discard-reporting-common {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:"
+ "ietf-packet-discard-reporting-common";
prefix pdr-common;
import ietf-yang-types {
prefix yang;
reference
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"RFC 9911: Common YANG Data Types";
}
organization
"IETF OPSAWG (Operations and Management Area Working Group)";
contact
"WG Web: https://datatracker.ietf.org/wg/opsawg/
WG List: OPSAWG <mailto:opsawg@ietf.org>
Editor: John Evans
<mailto:jevanamz@amazon.co.uk>
Editor: Oleksandr Pylypenko
<mailto:opylypenko@nvidia.com>
Author: Jeffrey Haas
<mailto:jhaas@juniper.net>
Author: Aviran Kadosh
<mailto:akadosh@cisco.com>
Editor: Mohamed Boucadair
<mailto:mohamed.boucadair@orange.com>";
description
"This module defines a common YANG module for packet discard
reporting.
Copyright (c) 2026 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).
All revisions of IETF and IANA published modules can be found
at the YANG Parameters registry group
(https://www.iana.org/assignments/yang-parameters).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2026-03-03 {
description
"Initial revision.";
reference
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"RFC XXXX: Information and Data Models for Packet Discard
Reporting";
}
/*
* Features
*/
feature control-plane-stats {
description
"Indicates support of control plane discard statistics.";
}
feature interface-stats {
description
"Indicates support of interface discard statistics.";
}
feature flow-reporting {
description
"Indicates support of flow discard reporting.";
}
feature device-stats {
description
"Indicates support of global device discard statistics.";
}
/*
* Identities
*/
identity direction {
description
"Defines a direction for the reported statistics.";
}
identity ingress {
base direction;
description
"Reports statistics for the received packets from
the network.";
}
identity egress {
base direction;
description
"Reports statistics for the sent packets to
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to the network.";
}
identity address-family {
description
"Defines a type for the address family.
This identity is defined here rather than importing
it from other YANG modules to simplify implementations
and avoid inheriting dependencies of those modules.
Additional address families can be added by defining
identities derived from this base identity, without
affecting existing implementations.";
}
identity ip {
base address-family;
description
"Identity for IP address family.";
}
identity ipv4 {
base ip;
description
"Identity for IPv4 address family.";
}
identity ipv6 {
base ip;
description
"Identity for IPv6 address family.";
}
/*
* Groupings
*/
grouping basic-packets {
description
"Grouping for packet counters.";
leaf packets {
type yang:counter64;
description
"Number of packets.";
}
}
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grouping basic-packets-bytes {
description
"Grouping for packet and byte counters.";
uses basic-packets;
leaf bytes {
type yang:counter64;
description
"Number of bytes.";
}
}
grouping basic-frames {
description
"Grouping for Layer 2 frame counters.";
leaf frames {
type yang:counter64;
description
"Number of Layer 2 frames.";
}
}
grouping l2-traffic {
description
"Grouping for Layer 2 frame and byte counters.";
uses basic-frames;
leaf bytes {
type yang:counter64;
description
"Number of Layer 2 bytes.";
}
}
grouping l3-traffic {
description
"Layer 3 traffic counters per address family.";
list address-family-stat {
key "address-family";
description
"Reports per address family traffic counters.";
leaf address-family {
type identityref {
base address-family;
}
description
"Specifies an address family.";
}
uses basic-packets-bytes;
container unicast {
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description
"Unicast traffic counters.";
uses basic-packets-bytes;
}
container multicast {
description
"Multicast traffic counters.";
uses basic-packets-bytes;
}
container broadcast {
when "derived-from-or-self(../address-family, "
+ "'pdr-common:ipv4')" {
description
"Only applicable for IPv4.";
}
description
"Broadcast traffic counters.";
uses basic-packets-bytes;
}
}
}
grouping class-list {
description
"Class-based traffic counters.";
list class {
key "id";
min-elements 1;
description
"Class traffic counters.";
leaf id {
type string;
description
"Indicates a Quality of Service (QoS) class
identifier.";
}
uses basic-packets-bytes;
}
}
grouping qos {
description
"QoS traffic counters.";
container qos {
presence "QoS statistics are available.";
description
"Per-class QoS traffic counters.";
uses class-list;
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}
}
grouping traffic {
description
"All traffic counters.";
container l2 {
description
"Layer 2 traffic counters.";
uses l2-traffic;
}
container l3 {
description
"Layer 3 traffic counters.";
uses l3-traffic;
}
uses qos;
}
grouping errors-l2-rx {
description
"Layer 2 ingress frame error discard counters.";
container rx {
description
"Layer 2 ingress frame receive error discard
counters.";
leaf frames {
type yang:counter64;
description
"The number of frames discarded due to errors
with the received frame.";
}
leaf crc-error {
type yang:counter64;
description
"The number of received frames discarded due to
Cyclic Redundancy Check (CRC) error.";
}
leaf invalid-mac {
type yang:counter64;
description
"The number of received frames discarded due to
an invalid Media Access Control (MAC) address.";
}
leaf invalid-vlan {
type yang:counter64;
description
"The number of received frames discarded due to
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an invalid VLAN tag.";
}
leaf invalid-frame {
type yang:counter64;
description
"The number of invalid received frames discarded due to
other reasons, not limited to: malformed frames,
frame-size violations.";
}
}
}
grouping errors-l3-rx {
description
"Layer 3 ingress packet error discard counters.";
container rx {
description
"Layer 3 ingress packet receive error discard
counters.";
leaf packets {
type yang:counter64;
description
"The number of Layer 3 packets discarded due to
errors in the received packet.";
}
leaf checksum-error {
type yang:counter64;
description
"The number of received packets discarded due
to a checksum error.";
}
leaf mtu-exceeded {
type yang:counter64;
description
"The number of received packets discarded due to
MTU exceeded.";
}
leaf invalid-packet {
type yang:counter64;
description
"The number of received invalid packets discarded due
to other reasons, not limited to: invalid packet length,
invalid header fields, invalid options, invalid protocol
version, invalid flags or control bits, malformed
packets.";
}
}
leaf ttl-expired {
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type yang:counter64;
description
"The number of received packets discarded due to
expired TTL or Hop Limit exceeded.";
}
leaf no-route {
type yang:counter64;
description
"The number of received packets discarded due to not
matching a valid route.";
}
leaf invalid-sid {
type yang:counter64;
description
"The number of received packets discarded due to an
invalid Segment Routing over IPv6 (SRv6) segment
identifier (SID).
For SR-MPLS, invalid SIDs have to be accounted
under invalid-label.";
}
leaf invalid-label {
type yang:counter64;
description
"The number of received packets discarded due to an
invalid MPLS label.";
}
}
grouping errors-l3-int {
description
"Internal error discard counters.";
leaf packets {
type yang:counter64;
description
"The number of packets discarded due to internal
errors.";
}
leaf parity-error {
type yang:counter64;
description
"The number of packets discarded due to parity
errors.";
}
}
grouping errors-l2-tx {
description
"Layer 2 transmit error discard counters.";
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container tx {
description
"Layer 2 transmit frame error discard counters.";
leaf frames {
type yang:counter64;
description
"The number of Layer 2 frames discarded due to
errors when transmitting.";
}
}
}
grouping errors-l3-tx {
description
"Layer 3 transmit error discard counters.";
container tx {
description
"Layer 3 transmit packet error discard counters.";
leaf packets {
type yang:counter64;
description
"The number of Layer 3 packets discarded due to
errors when transmitting.";
}
}
}
grouping errors {
description
"Error discard counters.";
container l2 {
description
"Layer 2 frame error discard counters.";
uses errors-l2-rx;
uses errors-l2-tx;
}
container l3 {
description
"Layer 3 packet error discard counters.";
uses errors-l3-rx;
uses errors-l3-tx;
}
container internal {
description
"Internal error discard counters.";
uses errors-l3-int;
}
}
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grouping policy-l2 {
description
"Layer 2 policy frame discard counters.";
leaf frames {
type yang:counter64;
description
"The number of Layer 2 frames discarded due
to policy.";
}
leaf acl {
type yang:counter64;
description
"The number of frames discarded due to Layer 2
Access Control Lists (ACLs).";
}
}
grouping policy-l3 {
description
"Layer 3 policy packet discard counters.";
leaf packets {
type yang:counter64;
description
"The number of Layer 3 packets discarded due to policy.";
}
leaf acl {
type yang:counter64;
description
"The number of packets discarded due to Layer 3 ACLs.";
}
container policer {
description
"The number of packets discarded due to policer
violations.";
uses basic-packets-bytes;
container classes {
presence "Per-class policer statistics are available.";
description
"Per-class policer discard counters.";
uses class-list;
}
}
leaf null-route {
type yang:counter64;
description
"The number of packets discarded due to matching
a null route.";
}
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leaf rpf {
type yang:counter64;
description
"The number of packets discarded due to failing
Reverse Path Forwarding (RPF) check.";
}
leaf ddos {
type yang:counter64;
description
"The number of packets discarded due to Distributed
Denial-of-Service (DDoS) protection policies.";
}
}
grouping discards {
description
"Discard counters.";
container l2 {
description
"Layer 2 frame discard counters.";
uses l2-traffic;
}
container l3 {
description
"Layer 3 packet discard counters.";
uses l3-traffic;
}
container errors {
description
"Error discard counters.";
uses errors;
}
container policy {
description
"Policy-related discard counters.";
uses policy;
}
container no-buffer {
description
"Discard counters due to buffer unavailability.";
uses qos;
}
}
grouping policy {
description
"Policy-related discard counters.";
container l2 {
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description
"Layer 2 policy frame discard counters.";
uses policy-l2;
}
container l3 {
description
"Layer 3 policy packet discard counters.";
uses policy-l3;
}
}
grouping traffic-and-discards {
description
"Specifies overall traffic and discard counters.";
container traffic {
description
"Traffic counters.";
uses traffic;
}
container discards {
description
"Discard counters.";
uses discards;
}
}
grouping interface {
description
"Interface-level traffic and discard counters.";
list traffic {
key "direction";
description
"Traffic counters.";
leaf direction {
type identityref {
base direction;
}
description
"Specifies a direction.";
}
uses traffic;
}
list discards {
key "direction";
description
"Discard counters.";
leaf direction {
type identityref {
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base direction;
}
description
"Specifies a direction.";
}
uses discards;
}
}
grouping control-plane {
description
"Control plane packet counters.";
list traffic {
key "direction";
description
"Total control plane packets.";
leaf direction {
type identityref {
base direction;
}
description
"Specifies a direction.";
}
uses basic-packets-bytes;
}
list discards {
key "direction";
description
"Control plane packet discard counters.";
leaf direction {
type identityref {
base direction;
}
description
"Specifies a direction.";
}
uses basic-packets-bytes;
container policy {
description
"Number of control plane packets discarded due to policy.";
uses basic-packets;
}
}
}
}
<CODE ENDS>
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4.4. "ietf-packet-discard-reporting-sx" YANG Module
The "ietf-packet-discard-reporting-sx" module uses the "sx" structure
defined in [RFC8791] and also imports the "ietf-packet-discard-
reporting-common" module (Section 4.3).
<CODE BEGINS> file "ietf-packet-discard-reporting-sx@2026-03-03.yang"
module ietf-packet-discard-reporting-sx {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-packet-discard-reporting-sx";
prefix pdr-sx;
import ietf-packet-discard-reporting-common {
prefix pdr-common;
reference
"RFC XXXX: Information and Data Models for Packet Discard
Reporting";
}
import ietf-yang-structure-ext {
prefix sx;
reference
"RFC 8791: YANG Data Structure Extensions";
}
organization
"IETF OPSAWG (Operations and Management Area Working Group)";
contact
"WG Web: https://datatracker.ietf.org/wg/opsawg/
WG List: OPSAWG <mailto:opsawg@ietf.org>
Editor: John Evans
<mailto:jevanamz@amazon.co.uk>
Editor: Oleksandr Pylypenko
<mailto:opylypenko@nvidia.com>
Author: Jeffrey Haas
<mailto:jhaas@juniper.net>
Author: Aviran Kadosh
<mailto:akadosh@cisco.com>
Editor: Mohamed Boucadair
<mailto:mohamed.boucadair@orange.com>";
description
"This module defines an information model for packet discard
reporting.
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Copyright (c) 2026 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).
All revisions of IETF and IANA published modules can be found
at the YANG Parameters registry group
(https://www.iana.org/assignments/yang-parameters).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2026-03-03 {
description
"Initial revision.";
reference
"RFC XXXX: Information and Data Models for Packet Discard
Reporting";
}
/*
* Main structure definition
*/
sx:structure packet-discard-reporting {
description
"Specifies the abstract structure of packet discard
reporting data.";
container control-plane {
if-feature "pdr-common:control-plane-stats";
description
"Control plane packet counters.";
uses pdr-common:control-plane;
}
list interface {
if-feature "pdr-common:interface-stats";
key "name";
description
"Indicates a list of interfaces for which packet
discard reporting data is provided.";
leaf name {
type string;
description
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"Indicates the name of the interface.";
}
uses pdr-common:interface;
}
list flow {
if-feature "pdr-common:flow-reporting";
key "direction";
leaf direction {
type identityref {
base pdr-common:direction;
}
description
"Specifies a direction.";
}
description
"Flow packet counters.";
uses pdr-common:traffic-and-discards;
}
container device {
if-feature "pdr-common:device-stats";
description
"Device level packet counters.";
uses pdr-common:traffic-and-discards;
}
}
}
<CODE ENDS>
5. Data Model (DM)
This DM implements the IM defined in Section 4 for the interface,
device, and control-plane components. It is a device model per
Section 2.1 of [RFC8969]. Specifically, it is a device-local
(network element) operational state model: counters are scoped to a
single device (interfaces and control plane).
The IM defines the abstract classification tree using YANG data
structure extensions [RFC8791]. This DM imports that module and
reuses the same groupings and hierarchy of components, directions,
layers, and discard classes, attaching them via augment statements to
existing YANG modules for routing, interfaces, and logical network
elements. The flow component is defined only in the IM for use by
flow-oriented data models and are not instantiated in this DM.
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5.1. Structure
There is a direct mapping between the IM components and their DM
implementations, with each component in the hierarchy represented by
corresponding YANG containers and leaf data nodes. The abstract tree
is shown in Figure 2.
module: ietf-packet-discard-reporting
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol:
+--ro traffic-discard-stats {control-plane-stats}?
+--ro discard-order-capability* identityref
+--ro traffic* [direction]
| ...
+--ro discards* [direction]
...
augment /if:interfaces/if:interface/if:statistics:
+--ro traffic-discard-stats {interface-stats}?
+--ro discard-order-capability* identityref?
+--ro traffic* [direction] {interface-stats}?
| +--ro direction identityref
| +--ro l2
| | ...
| +--ro l3
| | ...
| +--ro qos!
| +--ro class* [id]
| ...
+--ro discards* [direction]?
+--ro direction identityref
+--ro l2
| ...
+--ro l3
| ...
+--ro errors
| +--ro l2
| | ...
| +--ro l3
| | ...
| +--ro internal
| ...
+--ro policy
| +--ro l2
| | ...
| +--ro l3
| ...
+--ro no-buffer
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+--ro qos!
+--ro class* [id]
...
augment /lne:logical-network-elements/lne:logical-network-element:
+--ro traffic-discard-stats {device-stats}?
+--ro discard-order-capability* identityref
+--ro traffic
| +--ro l2
| | ...
| +--ro l3
| | ...
| +--ro qos!
| +--ro class* [id]
| ...
+--ro discards
+--ro l2
| ...
+--ro l3
| ...
+--ro errors
| +--ro l2
| | ...
| +--ro l3
| | ...
| +--ro internal
| ...
+--ro policy
| +--ro l2
| | ...
| +--ro l3
| ...
+--ro no-buffer
+--ro qos!
+--ro class* [id]
...
Figure 2: Abstract DM Tree Structure
The full tree structure is provided in Appendix D.
5.2. Implementation Requirements
The following requirements apply to the implementation of the DM and
are intended to ensure consistent implementation across different
vendors and platforms while allowing for platform-specific
optimisations where needed. While the DM defines a comprehensive set
of counters and statistics, implementations MAY support a subset of
the defined features based on device capabilities and operational
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requirements. However, implementations MUST clearly document which
features are supported and how they map to the DM.
Requirements 1-13 relate to packets forwarded or discarded by the
device, while requirement 14 relates to packets destined for or
originating from the device:
1. All instances of Layer 2 frame or Layer 3 packet receipt,
transmission, and discards MUST be accounted for.
2. All instances of Layer 2 frame or Layer 3 packet receipt,
transmission, and discards SHOULD be attributed to the physical
or logical interface of the device where they occur. Where they
cannot be attributed to the interface, they MUST be attributed
to the device.
3. An individual frame MUST only be accounted for by either the
Layer 2 traffic class or the Layer 2 discard classes within a
single direction or context, i.e., ingress or egress or device.
This is to avoid double counting.
4. An individual packet MUST only be accounted for by either the
Layer 3 traffic class or the Layer 3 discard classes within a
single direction or context, i.e., ingress or egress or device.
This is to avoid double counting.
5. A frame accounted for at Layer 2 MUST NOT be accounted for at
Layer 3 and vice versa. This is to avoid double counting.
6. The aggregate Layer 2 and Layer 3 traffic and discard classes
SHOULD account for all underlying frames or packets received,
transmitted, and discarded across all other classes. There
might be exceptions when distinct discontinuity times are
observed for more granular discards.
7. The aggregate QoS traffic and no-buffer discard classes MUST
account for all underlying packets received, transmitted, and
discarded across all other classes.
8. In addition to the Layer 2 and Layer 3 aggregate classes, an
individual discarded packet MUST only account against a single
error, policy, or no-buffer discard subclass.
9. When there are multiple reasons for discarding a packet, the
ordering of discard class reporting MUST be defined. Typically,
this can be exposed by an implementation by means of discard-
order-capability.
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10. If Diffserv [RFC2475] is not used, no-buffer discards MUST be
reported as class[id="0"], which represents the default class.
11. When traffic is mirrored, the discard metrics MUST account for
the original traffic rather than the reflected traffic.
12. No-buffer discards can be realized differently with different
memory architectures. Whether a no-buffer discard is attributed
to ingress or egress can differ accordingly. For successful
auto-mitigation, discards due to an egress interface congestion
MUST be reportable on egress, while discards due to device-level
congestion (e.g., due to exceeding the device forwarding rate)
MUST be reportable on ingress.
13. When the ingress and egress headers differ (for example, at a
tunnel endpoint), the discard class attribution MUST relate to
the outer header at the point of discard.
14. Traffic to the device control plane (to-CPU) has its own class.
Traffic from the device control plane (from-CPU) is accounted
for by origin, independent of the forwarding mechanism (e.g.,
any egress policer it traverses), and MUST also be accounted for
in the same way as other egress traffic.
5.3. Usage Examples
This section assumes that no class of service is implemented.
If all of the requirements listed in Section 5.2 are met, a "good"
unicast IPv4 packet received would increment:
* interface/traffic[direction="ingress"]/l3/address-family-
stat[address-family="ipv4"]/unicast/packets
* interface/traffic[direction="ingress"]/l3/address-family-
stat[address-family="ipv4"]/unicast/bytes
* interface/traffic[direction="ingress"]/qos/class[id="0"]/packets
* interface/traffic[direction="ingress"]/qos/class[id="0"]/bytes
A received unicast IPv6 packet discarded due to Hop Limit expiry
would increment:
* interface/discards[direction="ingress"]/errors/l3/ttl-expired
An IPv4 packet discarded on egress due to no buffers would increment:
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* interface/discards[direction="egress"]/l3/address-family-
stat[address-family="ipv4"]/unicast/packets
* interface/discards[direction="egress"]/l3/address-family-
stat[address-family="ipv4"]/unicast/bytes
* interface/discards[direction="egress"]/no-buffer/
class[id="0"]/packets
* interface/discards[direction="egress"]/no-buffer/
class[id="0"]/bytes
A multicast IPv6 packet dropped due to RPF check failure would
increment:
* interface/discards[direction="ingress"]/l3/address-family-
stat[address-family="ipv6"]/multicast/packets
* interface/discards[direction="ingress"]/l3/address-family-
stat[address-family="ipv6"]/multicast/bytes
* interface/discards[direction="ingress"]/policy/l3/rpf
A "good" Layer-2 frame received would increment:
* interface/traffic[direction="ingress"]/l2/frames
* interface/traffic[direction="ingress"]/l2/bytes
* interface/traffic[direction="ingress"]/qos/class[id="0"]/packets
* interface/traffic[direction="ingress"]/qos/class[id="0"]/bytes
5.4. "ietf-packet-discard-reporting" YANG Module
The "ietf-packet-discard-reporting" module imports "ietf-packet-
discard-reporting-common" (Section 4.3), "ietf-netconf-acm"
[RFC8341], "ietf-interfaces" [RFC8343], "ietf-routing" [RFC8349], and
"ietf-logical-network-element" [RFC8530].
<CODE BEGINS> file "ietf-packet-discard-reporting@2026-03-03.yang"
module ietf-packet-discard-reporting {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-packet-discard-reporting";
prefix pdr;
import ietf-packet-discard-reporting-common {
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prefix pdr-common;
reference
"RFC XXXX: Information and Data Models for Packet Discard
Reporting";
}
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 8341: Network Configuration Access Control Model";
}
import ietf-interfaces {
prefix if;
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-routing {
prefix rt;
reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA Version)";
}
import ietf-logical-network-element {
prefix lne;
reference
"RFC 8530: YANG Model for Logical Network Elements";
}
organization
"IETF OPSAWG (Operations and Management Area Working Group)";
contact
"WG Web: https://datatracker.ietf.org/wg/opsawg/
WG List: OPSAWG <mailto:opsawg@ietf.org>
Editor: John Evans
<mailto:jevanamz@amazon.co.uk>
Editor: Oleksandr Pylypenko
<mailto:opylypenko@nvidia.com>
Author: Jeffrey Haas
<mailto:jhaas@juniper.net>
Author: Aviran Kadosh
<mailto:akadosh@cisco.com>
Editor: Mohamed Boucadair
<mailto:mohamed.boucadair@orange.com>";
description
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"This module defines a data model for packet discard reporting.
Copyright (c) 2026 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).
All revisions of IETF and IANA published modules can be found
at the YANG Parameters registry
(https://www.iana.org/assignments/yang-parameters).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices.";
revision 2026-03-03 {
description
"Initial revision.";
reference
"RFC XXXX: Information and Data Models for Packet Discard
Reporting";
}
/*
* Identities
*/
identity discard-class {
description
"Base identity to identify the discard class.";
}
identity layer2 {
base discard-class;
description
"Indicates a Layer 2 discard.";
}
identity layer3 {
base discard-class;
description
"Indicates a Layer 3 discard.";
}
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identity internal {
base discard-class;
description
"Indicates an internal discard.";
}
identity policy {
base discard-class;
description
"Indicates a discard due to a policy.";
}
identity no-buffer {
base discard-class;
description
"Indicates a discard due to buffer unavailability.";
}
/*
* Groupings
*/
grouping discard-order-policy {
description
"Defines the implementation-specific precedence of discard
classes when multiple discard reasons apply to a single
packet.
The list is ordered from highest to lowest precedence.";
leaf-list discard-order-capability {
type identityref {
base discard-class;
}
config false;
description
"The discard class identity that has this precedence.";
}
}
/*
* Main structure definition
*/
augment "/rt:routing/rt:control-plane-protocols"
+ "/rt:control-plane-protocol" {
if-feature "pdr-common:control-plane-stats";
description
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"Adds control plane discard counters.";
container traffic-discard-stats {
nacm:default-deny-all;
config false;
description
"List of traffic and control plane discard counters.";
uses discard-order-policy;
uses pdr-common:control-plane;
}
}
augment "/if:interfaces/if:interface/if:statistics" {
if-feature "pdr-common:interface-stats";
description
"Adds traffic and discard reporting to the interface
statistics.";
container traffic-discard-stats {
nacm:default-deny-all;
config false;
description
"List of traffic and interface discard counters.";
uses discard-order-policy;
uses pdr-common:interface;
}
}
augment "/lne:logical-network-elements"
+ "/lne:logical-network-element" {
if-feature "pdr-common:device-stats";
description
"Adds device level traffic and discard counters.";
container traffic-discard-stats {
nacm:default-deny-all;
config false;
description
"List of traffic and device level discard counters.";
uses discard-order-policy;
uses pdr-common:traffic-and-discards;
}
}
}
<CODE ENDS>
6. Operational Considerations
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6.1. Determining Intent for Policy
Device discard counters do not by themselves establish operator
intent. Discards reported under policy (e.g., ACL/policer) indicate
only that traffic matched a configured rule; such discards may still
be unintended if the configuration is in error. Determining intent
for policy discards requires external context (e.g., configuration
validation and change history). Such contexts are local to each
operator.
6.2. Deployment Experience
This section captures practical insights gained from implementing the
model across multiple vendors' platforms, as guidance for future
implementers and operators:
1. The number and granularity of discard classes defined in the IM
represent a compromise. It aims to provide sufficient detail to
enable appropriate automated actions while avoiding excessive
detail, which may hinder quick problem identification.
Additionally, it helps to limit the quantity of data produced per
interface, constraining the data volume and device CPU impacts.
While further granularity is possible, the defined schema has
generally proven to be sufficient for the task of mitigating
unintended packet loss.
2. There are many possible ways to define the discard classification
tree. For example, an approach is to use a multi-rooted tree,
rooted in each protocol. Instead, a better approach is to define
a tree where protocol discards and causal discard classes are
accounted for orthogonally. This decision reduces the number of
combinations of classes and has proven sufficient for determining
mitigation actions.
3. Platforms often account for the number of packets discarded where
the TTL has expired (or IPv6 Hop Limit exceeded), and the device
CPU has returned an ICMP Time Exceeded message [RFC4884]. There
is typically a policer applied to limit the number of packets
sent to the device CPU, however, which implicitly limits the rate
of TTL discards that are processed. One method to account for
all packet discards due to TTL expired, even those that are
dropped by a policer when being forwarded to the CPU, is to use
accounting of all ingress packets received with TTL=1 as a proxy
measure.
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4. Where no route discards are implemented with a default null
route, separate discard accounting is required for any explicit
null routes configured in order to differentiate between
interface/ingress/discards/policy/null-route/packets and
interface/ingress/discards/errors/no-route/packets.
5. It is useful to account separately for transit packets discarded
by ACLs or policers, and packets discarded by ACLs or policers
which limit the number of packets to the device control plane.
6. It is not possible to identify a configuration error (e.g., when
intended discards are unintended) with device discard metrics
alone. For example, additional context is needed to determine if
ACL discards are intended or due to a misconfigured ACL (i.e.,
with configuration validation before deployment or by detecting a
significant change in ACL discards after a configuration change
compared to before).
7. Aggregate counters need to be able to deal with the possibility
of discontinuities in the underlying counters.
8. While the classification tree is seven levels deep, a minimal
implementation may only implement the top six.
6.3. Anchoring Flow Structure
The characterization of a flow depends on the underlying data model
that adheres to the IM. From that standpoint, the IM does not make
an assumption about flow characterization and identification. Future
flow-oriented data models MUST ensure that the flow structure is
anchored so that the discards are unambiguously associated with a
flow.
7. Implementation Status
Note to RFC Editor: This section is to be removed before publication
as an RFC.
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This section records the status of known implementations of the
protocol defined by this specification at the time of posting of this
Internet-Draft, and is based on a proposal described in RFC 7942.
The description of implementations in this section is intended to
assist the IETF in its decision processes in progressing drafts to
RFCs. Please note that the listing of any individual implementation
here does not imply endorsement by the IETF. Furthermore, no effort
has been spent to verify the information presented here that was
supplied by IETF contributors. This is not intended as, and must not
be construed to be, a catalog of available implementations or their
features. Readers are advised to note that other implementations may
exist.
7.1. Information Model Implementations
The IM defined in Section 4 has been implemented or mapped on at
least nine hardware platforms across four vendors, including:
* Broadcom: Trident, Tomahawk 1, Tomahawk 3, Tomahawk 5
* Cisco: Q200L
* Juniper: MX, PTX, QFX
* Marvell: TL7
7.2. Data Model Implementations
A YANG-compliant open-source SLAX script implements a subset of the
DM defined in Section 5 for Juniper MX routers. This implementation
is available at:
* https://github.com/o-pylypenko-aws/draft-ietf-opsawg-discardmodel-
sample/ (https://github.com/o-pylypenko-aws/draft-ietf-opsawg-
discardmodel-sample/)
Practical observations from these implementations are reflected in
Section 6.2.
8. Security Considerations
8.1. Information Model
The IM defined in Section 4.4 specifies a YANG module using [RFC8791]
data extensions. As such, there are no additional security issues
related to the YANG module that need to be considered.
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The "ietf-packet-discard-reporting-common" YANG module defines a set
of identities, types, and groupings. These nodes are intended to be
reused by other YANG modules. The module by itself does not expose
any data nodes that are writable, data nodes that contain read-only
state, or RPCs. As such, there are no additional security issues
related to the YANG module that need to be considered.
Modules that use the groupings that are defined in the "ietf-packet-
discard-reporting-common" module should identify the corresponding
security considerations.
8.2. Data Model
This section is modeled after the template described in Section 3.7.1
of [RFC9907].
The YANG module specified in Section 5.4 defines a data model that is
designed to be accessed via YANG-based management protocols, such as
Network Configuration Protocol (NETCONF) [RFC6241] and RESTCONF
[RFC8040]. These YANG-based management protocols (1) have to use a
secure transport layer (e.g., Secure Shell (SSH) [RFC4252], TLS
[RFC8446], and QUIC [RFC9000]) and (2) have to use mutual
authentication.
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 no particularly sensitive writable data nodes.
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. Specifically, the following
subtrees and data nodes have particular sensitivities/
vulnerabilities:
rt:control-plane-protocol/pdr:traffic-discard-stats,
if:statistics/pdr:traffic, if:statistics/pdr:traffic-discard-
stats, and lne:logical-network-element/pdr:traffic-discard-stats: Access
to these data nodes would reveal information about the attacks to
which an element is subject, misconfigurations, etc.
Also, an attacker who can inject packets can infer the efficiency
of its attack by monitoring (the increase of) some discard
counters (e.g., policy) and adjust its attack strategy
accordingly.
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9. IANA Considerations
IANA is requested to register the following URI in the "ns"
subregistry within the "IETF XML Registry" [RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-packet-discard-reporting-common
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-packet-discard-reporting-sx
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-packet-discard-reporting
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
IANA is requested to register the following YANG module in the "YANG
Module Names" subregistry [RFC6020] within the "YANG Parameters"
registry:
Name: ietf-packet-discard-reporting-common
Namespace:
urn:ietf:params:xml:ns:yang:ietf-packet-discard-reporting-common
Prefix: pdr-common
Maintained by IANA? N
Reference: RFC XXXX
Name: ietf-packet-discard-reporting-sx
Namespace: urn:ietf:params:xml:ns:yang:ietf-packet-discard-reporting-sx
Prefix: pdr-sx
Maintained by IANA? N
Reference: RFC XXXX
Name: ietf-packet-discard-reporting
Namespace: urn:ietf:params:xml:ns:yang:ietf-packet-discard-reporting
Prefix: pdr
Maintained by IANA? N
Reference: RFC XXXX
10. References
10.1. 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/rfc/rfc2119>.
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[RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.,
and W. Weiss, "An Architecture for Differentiated
Services", RFC 2475, DOI 10.17487/RFC2475, December 1998,
<https://www.rfc-editor.org/rfc/rfc2475>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/rfc/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/rfc/rfc6020>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/rfc/rfc7950>.
[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/rfc/rfc8174>.
[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/rfc/rfc8341>.
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/rfc/rfc8343>.
[RFC8349] Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
Routing Management (NMDA Version)", RFC 8349,
DOI 10.17487/RFC8349, March 2018,
<https://www.rfc-editor.org/rfc/rfc8349>.
[RFC8530] Berger, L., Hopps, C., Lindem, A., Bogdanovic, D., and X.
Liu, "YANG Model for Logical Network Elements", RFC 8530,
DOI 10.17487/RFC8530, March 2019,
<https://www.rfc-editor.org/rfc/rfc8530>.
[RFC8791] Bierman, A., Björklund, M., and K. Watsen, "YANG Data
Structure Extensions", RFC 8791, DOI 10.17487/RFC8791,
June 2020, <https://www.rfc-editor.org/rfc/rfc8791>.
[RFC9911] Schönwälder, J., Ed., "Common YANG Data Types", RFC 9911,
DOI 10.17487/RFC9911, December 2025,
<https://www.rfc-editor.org/rfc/rfc9911>.
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10.2. Informative References
[RED93] Floyd, S. and V. Jacobson, "Random early detection
gateways for congestion avoidance", August 1993,
<https://ieeexplore.ieee.org/document/251892>.
[RFC2827] Ferguson, P. and D. Senie, "Network Ingress Filtering:
Defeating Denial of Service Attacks which employ IP Source
Address Spoofing", BCP 38, RFC 2827, DOI 10.17487/RFC2827,
May 2000, <https://www.rfc-editor.org/rfc/rfc2827>.
[RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB", RFC 2863, DOI 10.17487/RFC2863, June 2000,
<https://www.rfc-editor.org/rfc/rfc2863>.
[RFC3444] Pras, A. and J. Schoenwaelder, "On the Difference between
Information Models and Data Models", RFC 3444,
DOI 10.17487/RFC3444, January 2003,
<https://www.rfc-editor.org/rfc/rfc3444>.
[RFC3704] Baker, F. and P. Savola, "Ingress Filtering for Multihomed
Networks", BCP 84, RFC 3704, DOI 10.17487/RFC3704, March
2004, <https://www.rfc-editor.org/rfc/rfc3704>.
[RFC3882] Turk, D., "Configuring BGP to Block Denial-of-Service
Attacks", RFC 3882, DOI 10.17487/RFC3882, October 2004,
<https://www.rfc-editor.org/rfc/rfc3882>.
[RFC4252] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252,
January 2006, <https://www.rfc-editor.org/rfc/rfc4252>.
[RFC4884] Bonica, R., Gan, D., Tappan, D., and C. Pignataro,
"Extended ICMP to Support Multi-Part Messages", RFC 4884,
DOI 10.17487/RFC4884, April 2007,
<https://www.rfc-editor.org/rfc/rfc4884>.
[RFC5635] Kumari, W. and D. McPherson, "Remote Triggered Black Hole
Filtering with Unicast Reverse Path Forwarding (uRPF)",
RFC 5635, DOI 10.17487/RFC5635, August 2009,
<https://www.rfc-editor.org/rfc/rfc5635>.
[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/rfc/rfc6241>.
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[RFC7011] Claise, B., Ed., Trammell, B., Ed., and P. Aitken,
"Specification of the IP Flow Information Export (IPFIX)
Protocol for the Exchange of Flow Information", STD 77,
RFC 7011, DOI 10.17487/RFC7011, September 2013,
<https://www.rfc-editor.org/rfc/rfc7011>.
[RFC7270] Yourtchenko, A., Aitken, P., and B. Claise, "Cisco-
Specific Information Elements Reused in IP Flow
Information Export (IPFIX)", RFC 7270,
DOI 10.17487/RFC7270, June 2014,
<https://www.rfc-editor.org/rfc/rfc7270>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/rfc/rfc8040>.
[RFC8289] Nichols, K., Jacobson, V., McGregor, A., Ed., and J.
Iyengar, Ed., "Controlled Delay Active Queue Management",
RFC 8289, DOI 10.17487/RFC8289, January 2018,
<https://www.rfc-editor.org/rfc/rfc8289>.
[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/rfc/rfc8340>.
[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/rfc/rfc8446>.
[RFC8704] Sriram, K., Montgomery, D., and J. Haas, "Enhanced
Feasible-Path Unicast Reverse Path Forwarding", BCP 84,
RFC 8704, DOI 10.17487/RFC8704, February 2020,
<https://www.rfc-editor.org/rfc/rfc8704>.
[RFC8955] Loibl, C., Hares, S., Raszuk, R., McPherson, D., and M.
Bacher, "Dissemination of Flow Specification Rules",
RFC 8955, DOI 10.17487/RFC8955, December 2020,
<https://www.rfc-editor.org/rfc/rfc8955>.
[RFC8956] Loibl, C., Ed., Raszuk, R., Ed., and S. Hares, Ed.,
"Dissemination of Flow Specification Rules for IPv6",
RFC 8956, DOI 10.17487/RFC8956, December 2020,
<https://www.rfc-editor.org/rfc/rfc8956>.
[RFC8969] Wu, Q., Ed., Boucadair, M., Ed., Lopez, D., Xie, C., and
L. Geng, "A Framework for Automating Service and Network
Management with YANG", RFC 8969, DOI 10.17487/RFC8969,
January 2021, <https://www.rfc-editor.org/rfc/rfc8969>.
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[RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
Multiplexed and Secure Transport", RFC 9000,
DOI 10.17487/RFC9000, May 2021,
<https://www.rfc-editor.org/rfc/rfc9000>.
[RFC9117] Uttaro, J., Alcaide, J., Filsfils, C., Smith, D., and P.
Mohapatra, "Revised Validation Procedure for BGP Flow
Specifications", RFC 9117, DOI 10.17487/RFC9117, August
2021, <https://www.rfc-editor.org/rfc/rfc9117>.
[RFC9907] Bierman, A., Boucadair, M., Ed., and Q. Wu, "Guidelines
for Authors and Reviewers of Documents Containing YANG
Data Models", BCP 216, RFC 9907, DOI 10.17487/RFC9907,
March 2026, <https://www.rfc-editor.org/rfc/rfc9907>.
Appendix A. Where Do Packets Get Dropped?
Understanding where packets are discarded in a network device is
essential for interpreting discard signals and determining
appropriate mitigation actions. Figure 3 depicts an example of where
and why packets may be discarded in a typical single-ASIC, shared-
buffered type device. While actual device architectures vary between
vendors and platforms, with some using multiple ASICs, distributed
forwarding, or different buffering architectures, this example
illustrates the common processing stages where packets may be
dropped. The logical model for classifying and reporting discards
remains consistent regardless of the underlying hardware
architecture.
Packets ingress on the left and egress on the right:
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.-----------.
| Control |
| Plane |
| |
'---+---^---'
from_cpu | | to_cpu
| |
.-----------------------v---+-----------------------.
| |
.---+---. .----------. .---------. .----------. .---+---.
| | | | | | | | | |
Rx-->PHY/MAC+--> Ingress +--> Buffers +--> Egress +-->PHY/MAC+-> Tx
| | | Pipeline | | | | Pipeline | | |
'-------' '----------' '---------' '----------' '-------'
Unintended:
errors/l2/rx errors/l3/rx no-buffer errors/l3/tx
errors/l3/no-route
errors/l3/ttl-expired
errors/internal
Intended:
policy/acl policy/acl
policy/policer policy/policer
policy/rpf
policy/null-route
Figure 3: Example of Where Packets Get Dropped
See Appendix B for examples of how these discard signals map to root
causes and mitigation actions.
Appendix B. Example Signal-to-mitigation Action Mapping
The effectiveness of automated mitigation depends on correctly
mapping discard signals to root causes and appropriate actions.
Tables 1 and 2 give example discard signal-to-mitigation action
mappings based on the features described in Section 3.
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+=============================+=============+============+========+
| DISCARD-CLASS | Discard | DISCARD- |DISCARD-|
| | cause | RATE |DURATION|
+=============================+=============+============+========+
| ingress/discards/errors/l2/ | Upstream | >Baseline |O(1min) |
| rx | device or | | |
| | link error | | |
+-----------------------------+-------------+------------+--------+
| ingress/discards/errors/l3/ | Tracert | <=Baseline | |
| ttl-expired | | | |
+-----------------------------+-------------+------------+--------+
| ingress/discards/errors/l3/ | Convergence | >Baseline | O(1s) |
| ttl-expired | | | |
+-----------------------------+-------------+------------+--------+
| ingress/discards/errors/l3/ | Routing | >Baseline |O(1min) |
| ttl-expired | loop | | |
+-----------------------------+-------------+------------+--------+
| .*/policy/.* | Policy | | |
+-----------------------------+-------------+------------+--------+
| ingress/discards/errors/l3/ | Convergence | >Baseline | O(1s) |
| no-route | | | |
+-----------------------------+-------------+------------+--------+
| ingress/discards/errors/l3/ | Config | >Baseline |O(1min) |
| no-route | error | | |
+-----------------------------+-------------+------------+--------+
| ingress/discards/errors/l3/ | Invalid | >Baseline |O(10min)|
| no-route | destination | | |
+-----------------------------+-------------+------------+--------+
| ingress/discards/errors/ | Device | >Baseline |O(1min) |
| internal | errors | | |
+-----------------------------+-------------+------------+--------+
| egress/discards/no-buffer | Congestion | <=Baseline | |
+-----------------------------+-------------+------------+--------+
| egress/discards/no-buffer | Congestion | >Baseline |O(1min) |
+-----------------------------+-------------+------------+--------+
Table 1: Example Signal-Cause-Mitigation Mapping (1)
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+=============================+=============+=======================+
| DISCARD-CLASS | Unintended? | Possible actions |
+=============================+=============+=======================+
| ingress/discards/errors/l2/ | Y | Take upstream |
| rx | | link or device |
| | | out-of-service |
+-----------------------------+-------------+-----------------------+
| ingress/discards/errors/l3/ | N | no action |
| ttl-expired | | |
+-----------------------------+-------------+-----------------------+
| ingress/discards/errors/l3/ | Y | No action |
| ttl-expired | | |
+-----------------------------+-------------+-----------------------+
| ingress/discards/errors/l3/ | Y | Roll-back change |
| ttl-expired | | |
+-----------------------------+-------------+-----------------------+
| .*/policy/.* | N | No action |
+-----------------------------+-------------+-----------------------+
| ingress/discards/errors/l3/ | Y | No action |
| no-route | | |
+-----------------------------+-------------+-----------------------+
| ingress/discards/errors/l3/ | Y | Roll-back change |
| no-route | | |
+-----------------------------+-------------+-----------------------+
| ingress/discards/errors/l3/ | N | Escalate to |
| no-route | | operator |
+-----------------------------+-------------+-----------------------+
| ingress/discards/errors/ | Y | Take device out- |
| internal | | of-service |
+-----------------------------+-------------+-----------------------+
| egress/discards/no-buffer | N | No action |
+-----------------------------+-------------+-----------------------+
| egress/discards/no-buffer | Y | Bring capacity |
| | | back into service |
| | | or move traffic |
+-----------------------------+-------------+-----------------------+
Table 2: Example Signal-Cause-Mitigation Mapping (2)
The 'Baseline' in the 'DISCARD-RATE' column is both DISCARD-CLASS and
network dependent.
Appendix C. Full Information Model Tree
The following YANG tree diagram shows the complete IM structure:
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module: ietf-packet-discard-reporting-sx
structure packet-discard-reporting:
+-- control-plane {pdr-common:control-plane-stats}?
| +-- traffic* [direction]
| | +-- direction identityref
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- discards* [direction]
| +-- direction identityref
| +-- packets? yang:counter64
| +-- bytes? yang:counter64
| +-- policy
| +-- packets? yang:counter64
+-- interface* [name] {pdr-common:interface-stats}?
| +-- name string
| +-- traffic* [direction]
| | +-- direction identityref
| | +-- l2
| | | +-- frames? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- l3
| | | +-- address-family-stat* [address-family]
| | | +-- address-family identityref
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | | +-- unicast
| | | | +-- packets? yang:counter64
| | | | +-- bytes? yang:counter64
| | | +-- multicast
| | | | +-- packets? yang:counter64
| | | | +-- bytes? yang:counter64
| | | +-- broadcast
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- qos!
| | +-- class* [id]
| | +-- id string
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- discards* [direction]
| +-- direction identityref
| +-- l2
| | +-- frames? yang:counter64
| | +-- bytes? yang:counter64
| +-- l3
| | +-- address-family-stat* [address-family]
| | +-- address-family identityref
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| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| | +-- unicast
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- multicast
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- broadcast
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- errors
| | +-- l2
| | | +-- rx
| | | | +-- frames? yang:counter64
| | | | +-- crc-error? yang:counter64
| | | | +-- invalid-mac? yang:counter64
| | | | +-- invalid-vlan? yang:counter64
| | | | +-- invalid-frame? yang:counter64
| | | +-- tx
| | | +-- frames? yang:counter64
| | +-- l3
| | | +-- rx
| | | | +-- packets? yang:counter64
| | | | +-- checksum-error? yang:counter64
| | | | +-- mtu-exceeded? yang:counter64
| | | | +-- invalid-packet? yang:counter64
| | | +-- ttl-expired? yang:counter64
| | | +-- no-route? yang:counter64
| | | +-- invalid-sid? yang:counter64
| | | +-- invalid-label? yang:counter64
| | | +-- tx
| | | +-- packets? yang:counter64
| | +-- internal
| | +-- packets? yang:counter64
| | +-- parity-error? yang:counter64
| +-- policy
| | +-- l2
| | | +-- frames? yang:counter64
| | | +-- acl? yang:counter64
| | +-- l3
| | +-- packets? yang:counter64
| | +-- acl? yang:counter64
| | +-- policer
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | | +-- classes!
| | | +-- class* [id]
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| | | +-- id string
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- null-route? yang:counter64
| | +-- rpf? yang:counter64
| | +-- ddos? yang:counter64
| +-- no-buffer
| +-- qos!
| +-- class* [id]
| +-- id string
| +-- packets? yang:counter64
| +-- bytes? yang:counter64
+-- flow* [direction] {pdr-common:flow-reporting}?
| +-- direction identityref
| +-- traffic
| | +-- l2
| | | +-- frames? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- l3
| | | +-- address-family-stat* [address-family]
| | | +-- address-family identityref
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | | +-- unicast
| | | | +-- packets? yang:counter64
| | | | +-- bytes? yang:counter64
| | | +-- multicast
| | | | +-- packets? yang:counter64
| | | | +-- bytes? yang:counter64
| | | +-- broadcast
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- qos!
| | +-- class* [id]
| | +-- id string
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- discards
| +-- l2
| | +-- frames? yang:counter64
| | +-- bytes? yang:counter64
| +-- l3
| | +-- address-family-stat* [address-family]
| | +-- address-family identityref
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| | +-- unicast
| | | +-- packets? yang:counter64
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| | | +-- bytes? yang:counter64
| | +-- multicast
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- broadcast
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- errors
| | +-- l2
| | | +-- rx
| | | | +-- frames? yang:counter64
| | | | +-- crc-error? yang:counter64
| | | | +-- invalid-mac? yang:counter64
| | | | +-- invalid-vlan? yang:counter64
| | | | +-- invalid-frame? yang:counter64
| | | +-- tx
| | | +-- frames? yang:counter64
| | +-- l3
| | | +-- rx
| | | | +-- packets? yang:counter64
| | | | +-- checksum-error? yang:counter64
| | | | +-- mtu-exceeded? yang:counter64
| | | | +-- invalid-packet? yang:counter64
| | | +-- ttl-expired? yang:counter64
| | | +-- no-route? yang:counter64
| | | +-- invalid-sid? yang:counter64
| | | +-- invalid-label? yang:counter64
| | | +-- tx
| | | +-- packets? yang:counter64
| | +-- internal
| | +-- packets? yang:counter64
| | +-- parity-error? yang:counter64
| +-- policy
| | +-- l2
| | | +-- frames? yang:counter64
| | | +-- acl? yang:counter64
| | +-- l3
| | +-- packets? yang:counter64
| | +-- acl? yang:counter64
| | +-- policer
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | | +-- classes!
| | | +-- class* [id]
| | | +-- id string
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- null-route? yang:counter64
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| | +-- rpf? yang:counter64
| | +-- ddos? yang:counter64
| +-- no-buffer
| +-- qos!
| +-- class* [id]
| +-- id string
| +-- packets? yang:counter64
| +-- bytes? yang:counter64
+-- device {pdr-common:device-stats}?
+-- traffic
| +-- l2
| | +-- frames? yang:counter64
| | +-- bytes? yang:counter64
| +-- l3
| | +-- address-family-stat* [address-family]
| | +-- address-family identityref
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| | +-- unicast
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- multicast
| | | +-- packets? yang:counter64
| | | +-- bytes? yang:counter64
| | +-- broadcast
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- qos!
| +-- class* [id]
| +-- id string
| +-- packets? yang:counter64
| +-- bytes? yang:counter64
+-- discards
+-- l2
| +-- frames? yang:counter64
| +-- bytes? yang:counter64
+-- l3
| +-- address-family-stat* [address-family]
| +-- address-family identityref
| +-- packets? yang:counter64
| +-- bytes? yang:counter64
| +-- unicast
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- multicast
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- broadcast
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| +-- packets? yang:counter64
| +-- bytes? yang:counter64
+-- errors
| +-- l2
| | +-- rx
| | | +-- frames? yang:counter64
| | | +-- crc-error? yang:counter64
| | | +-- invalid-mac? yang:counter64
| | | +-- invalid-vlan? yang:counter64
| | | +-- invalid-frame? yang:counter64
| | +-- tx
| | +-- frames? yang:counter64
| +-- l3
| | +-- rx
| | | +-- packets? yang:counter64
| | | +-- checksum-error? yang:counter64
| | | +-- mtu-exceeded? yang:counter64
| | | +-- invalid-packet? yang:counter64
| | +-- ttl-expired? yang:counter64
| | +-- no-route? yang:counter64
| | +-- invalid-sid? yang:counter64
| | +-- invalid-label? yang:counter64
| | +-- tx
| | +-- packets? yang:counter64
| +-- internal
| +-- packets? yang:counter64
| +-- parity-error? yang:counter64
+-- policy
| +-- l2
| | +-- frames? yang:counter64
| | +-- acl? yang:counter64
| +-- l3
| +-- packets? yang:counter64
| +-- acl? yang:counter64
| +-- policer
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| | +-- classes!
| | +-- class* [id]
| | +-- id string
| | +-- packets? yang:counter64
| | +-- bytes? yang:counter64
| +-- null-route? yang:counter64
| +-- rpf? yang:counter64
| +-- ddos? yang:counter64
+-- no-buffer
+-- qos!
+-- class* [id]
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+-- id string
+-- packets? yang:counter64
+-- bytes? yang:counter64
Appendix D. Full Data Model Tree
The following YANG tree diagram shows the complete DM structure:
module: ietf-packet-discard-reporting
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol:
+--ro traffic-discard-stats {pdr-common:control-plane-stats}?
+--ro discard-order-capability* identityref
+--ro traffic* [direction]
| +--ro direction identityref
| +--ro packets? yang:counter64
| +--ro bytes? yang:counter64
+--ro discards* [direction]
+--ro direction identityref
+--ro packets? yang:counter64
+--ro bytes? yang:counter64
+--ro policy
+--ro packets? yang:counter64
augment /if:interfaces/if:interface/if:statistics:
+--ro traffic-discard-stats {pdr-common:interface-stats}?
+--ro discard-order-capability* identityref
+--ro traffic* [direction]
| +--ro direction identityref
| +--ro l2
| | +--ro frames? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro l3
| | +--ro address-family-stat* [address-family]
| | +--ro address-family identityref
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| | +--ro unicast
| | | +--ro packets? yang:counter64
| | | +--ro bytes? yang:counter64
| | +--ro multicast
| | | +--ro packets? yang:counter64
| | | +--ro bytes? yang:counter64
| | +--ro broadcast
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro qos!
| +--ro class* [id]
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| +--ro id string
| +--ro packets? yang:counter64
| +--ro bytes? yang:counter64
+--ro discards* [direction]
+--ro direction identityref
+--ro l2
| +--ro frames? yang:counter64
| +--ro bytes? yang:counter64
+--ro l3
| +--ro address-family-stat* [address-family]
| +--ro address-family identityref
| +--ro packets? yang:counter64
| +--ro bytes? yang:counter64
| +--ro unicast
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro multicast
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro broadcast
| +--ro packets? yang:counter64
| +--ro bytes? yang:counter64
+--ro errors
| +--ro l2
| | +--ro rx
| | | +--ro frames? yang:counter64
| | | +--ro crc-error? yang:counter64
| | | +--ro invalid-mac? yang:counter64
| | | +--ro invalid-vlan? yang:counter64
| | | +--ro invalid-frame? yang:counter64
| | +--ro tx
| | +--ro frames? yang:counter64
| +--ro l3
| | +--ro rx
| | | +--ro packets? yang:counter64
| | | +--ro checksum-error? yang:counter64
| | | +--ro mtu-exceeded? yang:counter64
| | | +--ro invalid-packet? yang:counter64
| | +--ro ttl-expired? yang:counter64
| | +--ro no-route? yang:counter64
| | +--ro invalid-sid? yang:counter64
| | +--ro invalid-label? yang:counter64
| | +--ro tx
| | +--ro packets? yang:counter64
| +--ro internal
| +--ro packets? yang:counter64
| +--ro parity-error? yang:counter64
+--ro policy
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| +--ro l2
| | +--ro frames? yang:counter64
| | +--ro acl? yang:counter64
| +--ro l3
| +--ro packets? yang:counter64
| +--ro acl? yang:counter64
| +--ro policer
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| | +--ro classes!
| | +--ro class* [id]
| | +--ro id string
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro null-route? yang:counter64
| +--ro rpf? yang:counter64
| +--ro ddos? yang:counter64
+--ro no-buffer
+--ro qos!
+--ro class* [id]
+--ro id string
+--ro packets? yang:counter64
+--ro bytes? yang:counter64
augment /lne:logical-network-elements/lne:logical-network-element:
+--ro traffic-discard-stats {pdr-common:device-stats}?
+--ro discard-order-capability* identityref
+--ro traffic
| +--ro l2
| | +--ro frames? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro l3
| | +--ro address-family-stat* [address-family]
| | +--ro address-family identityref
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| | +--ro unicast
| | | +--ro packets? yang:counter64
| | | +--ro bytes? yang:counter64
| | +--ro multicast
| | | +--ro packets? yang:counter64
| | | +--ro bytes? yang:counter64
| | +--ro broadcast
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro qos!
| +--ro class* [id]
| +--ro id string
| +--ro packets? yang:counter64
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| +--ro bytes? yang:counter64
+--ro discards
+--ro l2
| +--ro frames? yang:counter64
| +--ro bytes? yang:counter64
+--ro l3
| +--ro address-family-stat* [address-family]
| +--ro address-family identityref
| +--ro packets? yang:counter64
| +--ro bytes? yang:counter64
| +--ro unicast
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro multicast
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro broadcast
| +--ro packets? yang:counter64
| +--ro bytes? yang:counter64
+--ro errors
| +--ro l2
| | +--ro rx
| | | +--ro frames? yang:counter64
| | | +--ro crc-error? yang:counter64
| | | +--ro invalid-mac? yang:counter64
| | | +--ro invalid-vlan? yang:counter64
| | | +--ro invalid-frame? yang:counter64
| | +--ro tx
| | +--ro frames? yang:counter64
| +--ro l3
| | +--ro rx
| | | +--ro packets? yang:counter64
| | | +--ro checksum-error? yang:counter64
| | | +--ro mtu-exceeded? yang:counter64
| | | +--ro invalid-packet? yang:counter64
| | +--ro ttl-expired? yang:counter64
| | +--ro no-route? yang:counter64
| | +--ro invalid-sid? yang:counter64
| | +--ro invalid-label? yang:counter64
| | +--ro tx
| | +--ro packets? yang:counter64
| +--ro internal
| +--ro packets? yang:counter64
| +--ro parity-error? yang:counter64
+--ro policy
| +--ro l2
| | +--ro frames? yang:counter64
| | +--ro acl? yang:counter64
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| +--ro l3
| +--ro packets? yang:counter64
| +--ro acl? yang:counter64
| +--ro policer
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| | +--ro classes!
| | +--ro class* [id]
| | +--ro id string
| | +--ro packets? yang:counter64
| | +--ro bytes? yang:counter64
| +--ro null-route? yang:counter64
| +--ro rpf? yang:counter64
| +--ro ddos? yang:counter64
+--ro no-buffer
+--ro qos!
+--ro class* [id]
+--ro id string
+--ro packets? yang:counter64
+--ro bytes? yang:counter64
Acknowledgements
The content of this document has benefitted from feedback from JR
Rivers, Ronan Waide, Chris DeBruin, and Marcos Sanz.
Thanks to Benoît Claise, Joe Clarke, Tom Petch, Mahesh Jethanandani,
Paul Aitken, and Randy Bush for the review and comments.
Thanks to Ladislav Lhotka for the YANGDOCTORS reviews, Sergio Belotti
for the OPSDIR review, Satoru Matsushima for the INTDIR review,
Derrell Piper for the SECDIR review, Roni Even for the GENART review,
and Michael Tüxen for the TSVART review.
Thanks to Diego Lopez for shepherding the document and Mahesh
Jethanandani for the AD review.
Contributors
Nadav Chachmon
Cisco Systems, Inc.
170 West Tasman Dr.
San Jose, CA 95134
United States of America
Email: nchachmo@cisco.com
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Authors' Addresses
John Evans (editor)
Amazon
1 Principal Place, Worship Street
London
EC2A 2FA
United Kingdom
Email: jevanamz@amazon.co.uk
Oleksandr Pylypenko (editor)
Nvidia
2788 San Tomas Expy
Santa Clara, CA 95051
United States of America
Email: opylypenko@nvidia.com
Jeffrey Haas
Juniper Networks
1133 Innovation Way
Sunnyvale, CA 94089
United States of America
Email: jhaas@juniper.net
Aviran Kadosh
Cisco Systems, Inc.
170 West Tasman Dr.
San Jose, CA 95134
United States of America
Email: akadosh@cisco.com
Mohamed Boucadair (editor)
Orange
France
Email: mohamed.boucadair@orange.com
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