RFC 9911
Common YANG Data Types
RFC 9911: Common YANG Data Types 🎀
Okay bestie, this is RFC 9911 💖, called Common YANG Data Types. J. Schönwälder, Ed. wrote it from Constructor University ✨. It's a Standards Track doc, so it's the real deal 👑, dated December 2025. It obsoletes RFC 6991 🦋, meaning it replaces that one, and its ISSN is 2070-1721.
Abstract 🌸
So this doc is basically a grab bag of common data types 🧺 you can use when you're writing YANG data models (YANG is the modeling language, obviously 💅). It adds several brand-new type definitions, and it replaces RFC 6991 😭.
Status of This Memo 🫶
This is an Internet Standards Track document, bestie 👑.
It's a product of the Internet Engineering Task Force (IETF) 🧚, so it represents the consensus of the IETF community ✨. It got public review and was approved for publication by the Internet Engineering Steering Group (IESG) 💅. If you want more on Internet Standards, check out Section 2 of RFC 7841 🌸.
Info about the current status, any errata, and how to send feedback lives at https://www.rfc-editor.org/info/rfc9911 🔗.
Copyright Notice 🌈
Copyright (c) 2025 belongs to the IETF Trust and the people listed 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) as they stand on the date of publication. Please read these carefully, because they spell out your rights and restrictions for this document 📜. Code Components pulled out of this document must include Revised BSD License text, as described in Section 4.e of the Trust Legal Provisions, and they come without warranty, as described in the Revised BSD License 🫧.
This document may contain material from IETF Documents or IETF Contributions that were published or made publicly available before November 10, 2008 🕰️. The people controlling the copyright in some of that material may not have given the IETF Trust permission to allow modifications outside the IETF Standards Process. So unless you get an adequate license from those copyright holders, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process 🚫. The one exception is formatting it for publication as an RFC or translating it into languages other than English 🌍.
1. Introduction ✨
Okay so YANG [RFC7950] is a data modeling language 🧠 used to model configuration and state data that gets manipulated by the Network Configuration Protocol (NETCONF) [RFC6241]. Yes, that's a lot of acronyms, I know 😭. YANG only comes with a small set of built-in data types, but it also gives you ways to derive new types from those built-ins 🎀.
This document defines a collection of common data types, and they're organized into two YANG modules 🦋:
- The
ietf-yang-typesmodule is the one with generally useful stuff, like types for counters and gauges, types for date and time, and types for common string values (e.g., UUIDs, dotted-quad notation, and language tags) 💖. - The
ietf-inet-typesmodule is for the Internet Protocol suite 🌐, with types for IP addresses, types for domain name, host name, URI, and email, and types for values in common protocol fields (e.g., port numbers) 🔥.
The first version of these YANG modules was published as [RFC6021] 🍓. The first revision of [RFC6021], published as [RFC6991], added several type definitions to the modules ✨. This second revision adds more new type definitions and addresses Erratum IDs 4076 [Err4076] and 5105 [Err5105] 💅. It also aligns the yang-identifier definition with YANG 1.1 [RFC7950] and improves some pattern statements 🫶. For the full details, check the revision statements of the YANG modules in Sections 3 and 4 📚. Want a quick overview of every type and when it showed up? That's in Section 2 💜. And more type definitions may be added later if people submit proposals to the NETMOD Working Group 🧚.
This document uses the YANG terminology defined in Section 3 of [RFC7950] 📖.
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 🎀.
2. Overview 🦋
Tables 1 and 2 list the types defined in the YANG modules "ietf-yang-types" and "ietf-inet-types" 💖. For each type, you get the name of the type, the base type it was derived from, and the RFC that introduced it 📋.
+=======================+===================+===============+
| Type | Base Type | Introduced in |
+=======================+===================+===============+
| counter32 | uint32 | RFC 6021 |
+-----------------------+-------------------+---------------+
| zero-based-counter32 | uint32 | RFC 6021 |
+-----------------------+-------------------+---------------+
| counter64 | uint64 | RFC 6021 |
+-----------------------+-------------------+---------------+
| zero-based-counter64 | uint64 | RFC 6021 |
+-----------------------+-------------------+---------------+
| gauge32 | uint32 | RFC 6021 |
+-----------------------+-------------------+---------------+
| gauge64 | uint64 | RFC 6021 |
+-----------------------+-------------------+---------------+
| object-identifier | string | RFC 6021 |
+-----------------------+-------------------+---------------+
| object-identifier-128 | object-identifier | RFC 6021 |
+-----------------------+-------------------+---------------+
| date-and-time | string | RFC 6021 |
+-----------------------+-------------------+---------------+
| date | string | RFC 9911 |
+-----------------------+-------------------+---------------+
| date-no-zone | string | RFC 9911 |
+-----------------------+-------------------+---------------+
| time | string | RFC 9911 |
+-----------------------+-------------------+---------------+
| time-no-zone | string | RFC 9911 |
+-----------------------+-------------------+---------------+
| hours32 | int32 | RFC 9911 |
+-----------------------+-------------------+---------------+
| minutes32 | int32 | RFC 9911 |
+-----------------------+-------------------+---------------+
| seconds32 | int32 | RFC 9911 |
+-----------------------+-------------------+---------------+
| centiseconds32 | int32 | RFC 9911 |
+-----------------------+-------------------+---------------+
| milliseconds32 | int32 | RFC 9911 |
+-----------------------+-------------------+---------------+
| microseconds32 | int32 | RFC 9911 |
+-----------------------+-------------------+---------------+
| microseconds64 | int64 | RFC 9911 |
+-----------------------+-------------------+---------------+
| nanoseconds32 | int32 | RFC 9911 |
+-----------------------+-------------------+---------------+
| nanoseconds64 | int64 | RFC 9911 |
+-----------------------+-------------------+---------------+
| timeticks | int32 | RFC 6021 |
+-----------------------+-------------------+---------------+
| timestamp | timeticks | RFC 6021 |
+-----------------------+-------------------+---------------+
| phys-address | string | RFC 6021 |
+-----------------------+-------------------+---------------+
| mac-address | string | RFC 6021 |
+-----------------------+-------------------+---------------+
| xpath1.0 | string | RFC 6021 |
+-----------------------+-------------------+---------------+
| hex-string | string | RFC 6991 |
+-----------------------+-------------------+---------------+
| uuid | string | RFC 6991 |
+-----------------------+-------------------+---------------+
| dotted-quad | string | RFC 6991 |
+-----------------------+-------------------+---------------+
| language-tag | string | RFC 9911 |
+-----------------------+-------------------+---------------+
| yang-identifier | string | RFC 6991 |
+-----------------------+-------------------+---------------+Table 1: Types Defined in the "ietf-yang-types" Module
Okay bestie, so the first table is the full lineup of types in ietf-inet-types and where each one came from 💅
+=============================+=================+===============+
| Type | Base Type | Introduced in |
+=============================+=================+===============+
| ip-version | enum | RFC 6021 |
+-----------------------------+-----------------+---------------+
| dscp | uint8 | RFC 6021 |
+-----------------------------+-----------------+---------------+
| ipv6-flow-label | uint32 | RFC 6021 |
+-----------------------------+-----------------+---------------+
| port-number | uint16 | RFC 6021 |
+-----------------------------+-----------------+---------------+
| protocol-number | uint8 | RFC 9911 |
+-----------------------------+-----------------+---------------+
| upper-layer-protocol-number | protocol-number | RFC 9911 |
+-----------------------------+-----------------+---------------+
| as-number | uint32 | RFC 6021 |
+-----------------------------+-----------------+---------------+
| ip-address | union | RFC 6021 |
+-----------------------------+-----------------+---------------+
| ipv4-address | string | RFC 6021 |
+-----------------------------+-----------------+---------------+
| ipv6-address | string | RFC 6021 |
+-----------------------------+-----------------+---------------+
| ip-address-no-zone | union | RFC 6991 |
+-----------------------------+-----------------+---------------+
| ipv4-address-no-zone | ipv4-address | RFC 6991 |
+-----------------------------+-----------------+---------------+
| ipv6-address-no-zone | ipv6-address | RFC 6991 |
+-----------------------------+-----------------+---------------+
| ip-address-link-local | union | RFC 9911 |
+-----------------------------+-----------------+---------------+
| ipv4-address-link-local | ipv4-address | RFC 9911 |
+-----------------------------+-----------------+---------------+
| ipv6-address-link-local | ipv6-address | RFC 9911 |
+-----------------------------+-----------------+---------------+
| ip-prefix | union | RFC 6021 |
+-----------------------------+-----------------+---------------+
| ipv4-prefix | string | RFC 6021 |
+-----------------------------+-----------------+---------------+
| ipv6-prefix | string | RFC 6021 |
+-----------------------------+-----------------+---------------+
| ip-address-and-prefix | union | RFC 9911 |
+-----------------------------+-----------------+---------------+
| ipv4-address-and-prefix | string | RFC 9911 |
+-----------------------------+-----------------+---------------+
| ipv6-address-and-prefix | string | RFC 9911 |
+-----------------------------+-----------------+---------------+
| domain-name | string | RFC 6021 |
+-----------------------------+-----------------+---------------+
| host-name | domain-name | RFC 9911 |
+-----------------------------+-----------------+---------------+
| host | union | RFC 6021 |
+-----------------------------+-----------------+---------------+
| uri | string | RFC 6021 |
+-----------------------------+-----------------+---------------+
| email-address | string | RFC 9911 |
+-----------------------------+-----------------+---------------+
Table 2: Types Defined in the "ietf-inet-types" ModuleSome of these types have a buddy in the old Structure of Management Information Version 2 (SMIv2) [RFC2578] [RFC2579] world 🦋 A YANG type counts as the same as an SMIv2 type when they cover the exact same set of values and mean the same thing, so no vibes-only matches here, it has to be a real match ✨
Table 3 lists the types in the "ietf-yang-types" YANG module next to their SMIv2 matches, and Table 4 does the same for the types in the "ietf-inet-types" module 💖
+=======================+================================+
| YANG type | Equivalent SMIv2 type (module) |
+=======================+================================+
| counter32 | Counter32 (SNMPv2-SMI) |
+-----------------------+--------------------------------+
| zero-based-counter32 | ZeroBasedCounter32 (RMON2-MIB) |
+-----------------------+--------------------------------+
| counter64 | Counter64 (SNMPv2-SMI) |
+-----------------------+--------------------------------+
| zero-based-counter64 | ZeroBasedCounter64 (HCNUM-TC) |
+-----------------------+--------------------------------+
| gauge32 | Gauge32 (SNMPv2-SMI) |
+-----------------------+--------------------------------+
| gauge64 | CounterBasedGauge64 (HCNUM-TC) |
+-----------------------+--------------------------------+
| object-identifier-128 | OBJECT IDENTIFIER |
+-----------------------+--------------------------------+
| centiseconds32 | TimeInterval (SNMPv2-TC) |
+-----------------------+--------------------------------+
| timeticks | TimeTicks (SNMPv2-SMI) |
+-----------------------+--------------------------------+
| timestamp | TimeStamp (SNMPv2-TC) |
+-----------------------+--------------------------------+
| phys-address | PhysAddress (SNMPv2-TC) |
+-----------------------+--------------------------------+
| mac-address | MacAddress (SNMPv2-TC) |
+-----------------------+--------------------------------+
| language-tag | LangTag (LANGTAG-TC-MIB) |
+-----------------------+--------------------------------+
Table 3: Equivalent SMIv2 Types for the "ietf-yang-
types" Module +=================+===============================================+
| YANG type | Equivalent SMIv2 type (module) |
+=================+===============================================+
| ip-version | InetVersion (INET-ADDRESS-MIB) |
+-----------------+-----------------------------------------------+
| dscp | Dscp (DIFFSERV-DSCP-TC) |
+-----------------+-----------------------------------------------+
| ipv6-flow-label | IPv6FlowLabel (IPV6-FLOW-LABEL-MIB) |
+-----------------+-----------------------------------------------+
| port-number | InetPortNumber (INET-ADDRESS-MIB) |
+-----------------+-----------------------------------------------+
| as-number | InetAutonomousSystemNumber (INET-ADDRESS-MIB) |
+-----------------+-----------------------------------------------+
| uri | Uri (URI-TC-MIB) |
+-----------------+-----------------------------------------------+
Table 4: Equivalent SMIv2 Types for the "ietf-inet-types" Module3. Core YANG Types 🎀
The "ietf-yang-types" YANG module pulls in a whole squad of references: [IEEE-802-2024], [ISO-8601], [ISO-9834-1], [RFC2578], [RFC2579], [RFC2856], [RFC3339], [RFC4502], [RFC5131], [RFC5646], [RFC7950], [RFC9557], [RFC9562], [XPATH], and [XSD-TYPES] 🫶
Here's the module itself, so you can see every single type in it 👑
<CODE BEGINS> file "ietf-yang-types@2025-12-22.yang"
module ietf-yang-types {
namespace "urn:ietf:params:xml:ns:yang:ietf-yang-types";
prefix yang;
organization
"IETF Network Modeling (NETMOD) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/netmod/>
WG List: <mailto:netmod@ietf.org>
Editor: Jürgen Schönwälder
<mailto:jschoenwaelder@constructor.university>";
description
"This module contains a collection of generally useful derived
YANG data types.
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) 2025 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 9911;
see the RFC itself for full legal notices.";
revision 2025-12-22 {
description
"This revision adds the following new data types:
- yang:date
- yang:date-no-zone
- yang:time
- yang:time-no-zone
- yang:hours32
- yang:minutes32
- yang:seconds32
- yang:centiseconds32
- yang:milliseconds32
- yang:microseconds32
- yang:microseconds64
- yang:nanoseconds32
- yang:nanoseconds64
- yang:language-tag
The yang-identifier definition has been aligned with YANG
1.1, and types representing time support the representation
of leap seconds. The representation of time zone offsets
has been aligned with RFC 9557. Several description and
pattern statements have been improved.";
reference
"RFC 9911: Common YANG Data Types";
}
revision 2013-07-15 {
description
"This revision adds the following new data types:
- yang:yang-identifier
- yang:hex-string
- yang:uuid
- yang:dotted-quad";
reference
"RFC 6991: Common YANG Data Types";
}
revision 2010-09-24 {
description
"Initial revision.";
reference
"RFC 6021: Common YANG Data Types";
}
/*** collection of counter and gauge types ***/
typedef counter32 {
type uint32;
description
"The counter32 type represents a non-negative integer
that monotonically increases until it reaches a
maximum value of 2^32-1 (4294967295 decimal), when it
wraps around and starts increasing again from zero.
Counters have no defined 'initial' value, and thus, a
single value of a counter has (in general) no information
content. Discontinuities in the monotonically increasing
value normally occur at re-initialization of the
management system and at other times as specified in the
description of a schema node using this type. If
discontinuities occur at times other than re-initialization
(for example, at the instantiation of a schema node of type
counter32), then a corresponding schema node should be
defined, with an appropriate type, to indicate the last
discontinuity. The counter32 type should not be used for configuration
schema nodes. A default statement SHOULD NOT be used in
combination with the type counter32.
In the value set and its semantics, this type is equivalent
to the Counter32 type of the SMIv2.";
reference
"RFC 2578: Structure of Management Information Version 2
(SMIv2)";
}
typedef zero-based-counter32 {
type counter32;
default "0";
description
"The zero-based-counter32 type represents a counter32
that has the defined 'initial' value zero.
A data tree node using this type will be set to zero (0)
on creation and will thereafter increase monotonically until
it reaches a maximum value of 2^32-1 (4294967295 decimal),
when it wraps around and starts increasing again from zero.
Provided that an application discovers a new data tree node
using this type within the minimum time to wrap, it can use
the 'initial' value as a delta. It is important for a
management station to be aware of this minimum time and the
actual time between polls, and to discard data if the actual
time is too long or there is no defined minimum time.
In the value set and its semantics, this type is equivalent
to the ZeroBasedCounter32 textual convention of the SMIv2.";
reference
"RFC 4502: Remote Network Monitoring Management Information
Base Version 2";
}
typedef counter64 {
type uint64;
description
"The counter64 type represents a non-negative integer
that monotonically increases until it reaches a
maximum value of 2^64-1 (18446744073709551615 decimal),
when it wraps around and starts increasing again from zero.
Counters have no defined 'initial' value, and thus, a
single value of a counter has (in general) no information
content. Discontinuities in the monotonically increasing
value normally occur at re-initialization of the
management system and at other times as specified in the
description of a schema node using this type. If
discontinuities occur at times other than re-initialization
(for example, at the instantiation of a schema node of type
counter64), then a corresponding schema node should be
defined, with an appropriate type, to indicate the last
discontinuity.
The counter64 type should not be used for configuration
schema nodes. A default statement SHOULD NOT be used in
combination with the type counter64.
In the value set and its semantics, this type is equivalent
to the Counter64 type of the SMIv2.";
reference
"RFC 2578: Structure of Management Information Version 2
(SMIv2)";
}
typedef zero-based-counter64 {
type counter64;
default "0";
description
"The zero-based-counter64 type represents a counter64 that
has the defined 'initial' value zero.
A data tree node using this type will be set to zero (0)
on creation and will thereafter increase monotonically until
it reaches a maximum value of 2^64-1 (18446744073709551615
decimal), when it wraps around and starts increasing again
from zero.
Provided that an application discovers a new data tree node
using this type within the minimum time to wrap, it can use
the 'initial' value as a delta. It is important for a
management station to be aware of this minimum time and the
actual time between polls, and to discard data if the actual
time is too long or there is no defined minimum time.
In the value set and its semantics, this type is equivalent
to the ZeroBasedCounter64 textual convention of the SMIv2.";
reference
"RFC 2856: Textual Conventions for Additional High Capacity
Data Types";
}
typedef gauge32 {
type uint32;
description
"The gauge32 type represents a non-negative integer, which
may increase or decrease, but shall never exceed a maximum
value, nor fall below a minimum value. The maximum value
cannot be greater than 2^32-1 (4294967295 decimal), and
the minimum value cannot be smaller than 0. The value of
a gauge32 has its maximum value whenever the information
being modeled is greater than or equal to its maximum
value, and has its minimum value whenever the information
being modeled is smaller than or equal to its minimum value.
If the information being modeled subsequently decreases below
the maximum value, the gauge32 also decreases; likewise, if
the information increases above the minimum value, the
gauge32 also increases.
In the value set and its semantics, this type is equivalent
to the Gauge32 type of the SMIv2.";
reference
"RFC 2578: Structure of Management Information Version 2
(SMIv2)";
}
typedef gauge64 {
type uint64;
description
"The gauge64 type represents a non-negative integer, which
may increase or decrease, but shall never exceed a maximum
value, nor fall below a minimum value. The maximum value
cannot be greater than 2^64-1 (18446744073709551615), and
the minimum value cannot be smaller than 0. The value of
a gauge64 has its maximum value whenever the information
being modeled is greater than or equal to its maximum
value, and has its minimum value whenever the information
being modeled is smaller than or equal to its minimum value.
If the information being modeled subsequently decreases
below (increases above) the maximum (minimum) value, the
gauge64 also decreases (increases).
In the value set and its semantics, this type is equivalent
to the CounterBasedGauge64 SMIv2 textual convention defined
in RFC 2856";
reference
"RFC 2856: Textual Conventions for Additional High Capacity
Data Types";
}
/*** collection of identifier-related types ***/
typedef object-identifier {
type string {
pattern '(([0-1](\.[1-3]?[0-9]))|(2\.(0|([1-9][0-9]*))))'
+ '(\.(0|([1-9][0-9]*)))*';
}
description
"The object-identifier type represents administratively
assigned names in a registration-hierarchical-name tree.
Values of this type are denoted as a sequence of numerical
non-negative sub-identifier values. Each sub-identifier
value MUST NOT exceed 2^32-1 (4294967295). Sub-identifiers
are separated by single dots and without any intermediate
whitespace.
The ASN.1 standard restricts the value space of the first
sub-identifier to 0, 1, or 2. Furthermore, the value space
of the second sub-identifier is restricted to the range
0 to 39 if the first sub-identifier is 0 or 1. Finally,
the ASN.1 standard requires that an object identifier
has always at least two sub-identifiers. The pattern
captures these restrictions.
Although the number of sub-identifiers is not limited,
module designers should realize that there may be
implementations that stick with the SMIv2 limit of 128
sub-identifiers.
This type is a superset of the SMIv2 OBJECT IDENTIFIER type
since it is not restricted to 128 sub-identifiers. Hence,
this type SHOULD NOT be used to represent the SMIv2 OBJECT
IDENTIFIER type; the object-identifier-128 type SHOULD be
used instead.";
reference
"ISO 9834-1: Information technology -- Procedures for the
operation of object identifier registration authorities --
Part 1: General procedures and top arcs of the international
object identifier tree";
}
typedef object-identifier-128 {
type object-identifier {
pattern '[0-9]*(\.[0-9]*){1,127}';
}
description
"This type represents object-identifiers restricted to 128
sub-identifiers.
In the value set and its semantics, this type is equivalent
to the OBJECT IDENTIFIER type of the SMIv2.";
reference
"RFC 2578: Structure of Management Information Version 2
(SMIv2)";
}
/*** collection of types related to date and time ***/
typedef date-and-time {
type string {
pattern
'[0-9]{4}-(1[0-2]|0[1-9])-(0[1-9]|[1-2][0-9]|3[0-1])'
+ 'T(0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]:([0-5][0-9]|60)'
+ '(\.[0-9]+)?'
+ '(Z|[\+\-]((1[0-3]|0[0-9]):([0-5][0-9])|14:00))?';
}
description
"The date-and-time type is a profile of the ISO 8601
standard for representation of dates and times using the
Gregorian calendar. The profile is defined by the
date-time production in Section 5.6 of RFC 3339 and the
update defined in Section 2 of RFC 9557. The value of
60 for seconds is allowed only in the case of leap seconds.
The date-and-time type is compatible with the dateTime XML
schema dateTime type with the following notable exceptions:
(a) The date-and-time type does not allow negative years.
(b) The time-offset Z indicates that the date-and-time
value is reported in UTC and that the local time zone
reference point is unknown. The time-offset +00:00
indicates that the date-and-time value is reported in
UTC and that the local time zone reference point is UTC
(see Section 2 of RFC 9557).
This type is not equivalent to the DateAndTime textual
convention of the SMIv2 since RFC 3339 uses a different
separator between full-date and full-time and provides
higher resolution of time-secfrac.
The canonical format for date-and-time values with a known
time zone uses a numeric time zone offset that is calculated
using the device's configured known offset to UTC time. A
change of the device's offset to UTC time will cause
date-and-time values to change accordingly. Such changes
might happen periodically if a server automatically follows
daylight saving time (DST) time zone offset changes. The
canonical format for date-and-time values reported in UTC
with an unknown local time zone offset SHOULD use the
time-offset Z and MAY use -00:00 for backwards
compatibility.";
reference
"ISO 8601: Data elements and interchange formats -- Information
interchange -- Representation of dates and times
RFC 3339: Date and Time on the Internet: Timestamps
RFC 9557: Date and Time on the Internet: Timestamps
with Additional Information
RFC 2579: Textual Conventions for SMIv2
XSD-TYPES: XML Schema Definition Language (XSD) 1.1
Part 2: Datatypes";
}Okay, the counters bit is giving 💖 the wrap-around stuff, the 2^32-1 and 2^64-1 limits, is literally the main character of this section 🎀
And the timestamp type is the whole vibe 🦋 with the Z versus +00:00 distinction ✨
Okay bestie, now we're getting into the date and time typedefs, and they're giving precision. 🕰️✨ Dates are a full day (24 hours) with an optional time zone offset. Let's look at the date type first 💅
typedef date {
type string {
pattern '[0-9]{4}-(1[0-2]|0[1-9])-(0[1-9]|[1-2][0-9]|3[0-1])'
+ '(Z|[\+\-]((1[0-3]|0[0-9]):([0-5][0-9])|14:00))?';
}
description
"The date type represents a time-interval of the length
of a day, i.e., 24 hours. It includes an optional time
zone offset.
The date type is compatible with the XML schema date
type with the following notable exceptions:
(a) The date type does not allow negative years.
(b) The time-offset Z indicates that the date value is
reported in UTC and that the local time zone reference
point is unknown. The time-offset +00:00 indicates that
the date value is reported in UTC and that the local
time zone reference point is UTC (see Section 2 of
RFC 9557).
The canonical format for date values with a known time
zone uses a numeric time zone offset that is calculated using
the device's configured known offset to UTC time. A change of
the device's offset to UTC time will cause date values
to change accordingly. Such changes might happen periodically
if a server automatically follows daylight saving time
(DST) time zone offset changes. The canonical format for
date values reported in UTC with an unknown local time zone
offset uses the time-offset Z.";
reference
"RFC 3339: Date and Time on the Internet: Timestamps
RFC 9557: Date and Time on the Internet: Timestamps
with Additional Information
XSD-TYPES: XML Schema Definition Language (XSD) 1.1
Part 2: Datatypes";
}
typedef date-no-zone {
type date {
pattern '[0-9]{4}-(1[0-2]|0[1-9])-(0[1-9]|[1-2][0-9]|3[0-1])';
}
description
"The date-no-zone type represents a date without the optional
time zone offset information.";
}The date-no-zone type is basically the same date, just without the optional zone part. Simple, clean, no drama 🎀
Now the time types, which work the same way but for a time of day that repeats every single day 🌸
typedef time {
type string {
pattern
'(0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]:([0-5][0-9]|60)'
+ '(\.[0-9]+)?'
+ '(Z|[\+\-]((1[0-3]|0[0-9]):([0-5][0-9])|14:00))?';
}
description
"The time type represents an instance of time of zero duration
that recurs every day. It includes an optional time zone
offset. The value of 60 for seconds is allowed only in the
case of leap seconds.
The time type is compatible with the XML schema time
type with the following notable exception:
(a) The time-offset Z indicates that the time value is
reported in UTC and that the local time zone reference
point is unknown. The time-offset +00:00 indicates that
the time value is reported in UTC and that the local
time zone reference point is UTC (see Section 2 of
RFC 9557).
The canonical format for time values with a known time
zone uses a numeric time zone offset that is calculated using
the device's configured known offset to UTC time. A change of
the device's offset to UTC time will cause time values
to change accordingly. Such changes might happen periodically
if a server automatically follows daylight saving time
(DST) time zone offset changes. The canonical format for
time values reported in UTC with an unknown local time zone
offset uses the time-offset Z.";
reference
"RFC 3339: Date and Time on the Internet: Timestamps
RFC 9557: Date and Time on the Internet: Timestamps
with Additional Information
XSD-TYPES: XML Schema Definition Language (XSD) 1.1
Part 2: Datatypes";
}
typedef time-no-zone {
type time {
pattern
'(0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]:([0-5][0-9]|60)'
+ '(\.[0-9]+)?';
}
description
"The time-no-zone type represents a time without the optional
time zone offset information.";
}Next up are the duration types 🦋 Each one is an int32 or int64 with a unit, and there's a range that tells you how big a period it can hold. They all have the same little tip about range-restricting when only non-negative values make sense, so yep, that's a whole pattern. Let's go 💜
typedef hours32 {
type int32;
units "hours";
description
"A period of time measured in units of hours.
The maximum time period that can be expressed is in the
range [-89478485 days 08:00:00 to 89478485 days 07:00:00].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}
typedef minutes32 {
type int32;
units "minutes";
description
"A period of time measured in units of minutes.
The maximum time period that can be expressed is in the
range [-1491308 days 2:08:00 to 1491308 days 2:07:00].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}
typedef seconds32 {
type int32;
units "seconds";
description
"A period of time measured in units of seconds.
The maximum time period that can be expressed is in the
range [-24855 days 03:14:08 to 24855 days 03:14:07].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}
typedef centiseconds32 {
type int32;
units "centiseconds";
description
"A period of time measured in units of 10^-2 seconds.
The maximum time period that can be expressed is in the
range [-248 days 13:13:56 to 248 days 13:13:56].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}
typedef milliseconds32 {
type int32;
units "milliseconds";
description
"A period of time measured in units of 10^-3 seconds.
The maximum time period that can be expressed is in the
range [-24 days 20:31:23 to 24 days 20:31:23].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}
typedef microseconds32 {
type int32;
units "microseconds";
description
"A period of time measured in units of 10^-6 seconds.
The maximum time period that can be expressed is in the
range [-00:35:47 to 00:35:47].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}
typedef microseconds64 {
type int64;
units "microseconds";
description
"A period of time measured in units of 10^-6 seconds.
The maximum time period that can be expressed is in the
range [-106751991 days 04:00:54 to 106751991 days 04:00:54].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}
typedef nanoseconds32 {
type int32;
units "nanoseconds";
description
"A period of time measured in units of 10^-9 seconds.
The maximum time period that can be expressed is in the
range [-00:00:02 to 00:00:02].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}
typedef nanoseconds64 {
type int64;
units "nanoseconds";
description
"A period of time measured in units of 10^-9 seconds.
The maximum time period that can be expressed is in the
range [-106753 days 23:12:44 to 106752 days 0:47:16].
This type should be range-restricted in situations
where only non-negative time periods are desirable
(i.e., range '0..max').";
}Now we're in the timeticks zone ⏱️ These are counters measured in hundredths of a second, and they wrap around modulo 2^32 (that's 4294967296 in decimal, bestie 🙈). They're tied to SMIv2, so the reference is there too.
typedef timeticks {
type uint32;
description
"The timeticks type represents a non-negative integer that
represents the time, modulo 2^32 (4294967296 decimal), in
hundredths of a second between two epochs. When a schema
node is defined that uses this type, the description of
the schema node identifies both of the reference epochs.
In the value set and its semantics, this type is equivalent
to the TimeTicks type of the SMIv2.";
reference
"RFC 2578: Structure of Management Information Version 2
(SMIv2)";
}
typedef timestamp {
type timeticks;
description
"The timestamp type represents the value of an associated
timeticks schema node instance at which a specific occurrence
happened. The specific occurrence must be defined in the
description of any schema node defined using this type. When
the specific occurrence occurred prior to the last time the
associated timeticks schema node instance was zero, then the
timestamp value is zero.
Note that this requires all timestamp values to be reset to
zero when the value of the associated timeticks schema node
instance reaches 497+ days and wraps around to zero.
The associated timeticks schema node must be specified
in the description of any schema node using this type.
In the value set and its semantics, this type is equivalent
to the TimeStamp textual convention of the SMIv2.";
reference
"RFC 2579: Textual Conventions for SMIv2";
}Okay, the generic address types are next, and these are where things get juicy 🌈 phys-address is a sequence of hex octets separated by colons, and mac-address is the specific 48-bit IEEE 802 flavour. Notice the mac-address one can't do the other lengths, which is why phys-address exists for those.
/*** collection of generic address types ***/
typedef phys-address {
type string {
pattern '([0-9a-fA-F]{2}(:[0-9a-fA-F]{2})*)?';
}
description
"Represents media- or physical-level addresses represented
as a sequence of octets, each octet represented by two
hexadecimal numbers. Octets are separated by colons. The
canonical representation uses lowercase characters.
In the value set and its semantics, this type is equivalent
to the PhysAddress textual convention of the SMIv2.";
reference
"RFC 2579: Textual Conventions for SMIv2";
}
typedef mac-address {
type string {
pattern '[0-9a-fA-F]{2}(:[0-9a-fA-F]{2}){5}';
}
description
"The mac-address type represents a 48-bit IEEE 802 Media
Access Control (MAC) address. The canonical representation
uses lowercase characters. Note that there are IEEE 802 MAC
addresses with a different length that this type cannot
represent. The phys-address type may be used to represent
physical addresses of varying length.
In the value set and its semantics, this type is equivalent
to the MacAddress textual convention of the SMIv2.";
reference
"IEEE 802: IEEE Standard for Local and Metropolitan Area
Networks: Overview and Architecture
RFC 2579: Textual Conventions for SMIv2";
}Last bit of this chunk: the XML-specific XPath type. The important bit is the MUST in the description, which says any schema node using this type has to say what XPath context the expression gets evaluated in. That's a strict one, so it stays in full caps 🔥
/*** collection of XML-specific types ***/
typedef xpath1.0 {
type string;
description
"This type represents an XPATH 1.0 expression.
When a schema node is defined that uses this type, the
description of the schema node MUST specify the XPath
context in which the XPath expression is evaluated.";
reference
"XPATH: XML Path Language (XPath) Version 1.0";
}
/*** collection of string types ***/ typedef hex-string {
type string {
pattern '([0-9a-fA-F]{2}(:[0-9a-fA-F]{2})*)?';
}
description
"A hexadecimal string with octets represented as hex digits
separated by colons. The canonical representation uses
lowercase characters.";
}
typedef uuid {
type string {
pattern '[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-'
+ '[0-9a-fA-F]{4}-[0-9a-fA-F]{12}';
}
description
"A Universally Unique IDentifier in the string representation
defined in RFC 9562. The canonical representation uses
lowercase characters.
The following is an example of a UUID in string
representation:
f81d4fae-7dec-11d0-a765-00a0c91e6bf6.
";
reference
"RFC 9562: Universally Unique IDentifiers (UUIDs)";
}
typedef dotted-quad {
type string {
pattern
'(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.){3}'
+ '([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])';
}
description
"An unsigned 32-bit number expressed in the dotted-quad
notation, i.e., four octets written as decimal numbers
and separated with the '.' (full stop) character.";
}
typedef language-tag {
type string;
description
"A language tag according to RFC 5646 (BCP 47). The
canonical representation uses lowercase characters.
Values of this type must be well-formed language tags,
in conformance with the definition of well-formed tags
in BCP 47. Implementations MAY further limit the values
they accept to those permitted by a 'validating'
processor, as defined in BCP 47.
The canonical representation of values of this type is
aligned with the SMIv2 LangTag textual convention for
language tags fitting the length constraints imposed
by the LangTag textual convention.";
reference
"RFC 5646: Tags for Identifying Languages
RFC 5131: A MIB Textual Convention for Language Tags";
}
/*** collection of YANG-specific types ***/
typedef yang-identifier {
type string {
length "1..max";
pattern '[a-zA-Z_][a-zA-Z0-9\-_.]*';
}
description
"A YANG identifier string as defined by the 'identifier'
rule in Section 14 of RFC 7950. An identifier must
start with an alphabetic character or an underscore
followed by an arbitrary sequence of alphabetic or
numeric characters, underscores, hyphens, or dots.
This definition conforms to YANG 1.1 defined in RFC
7950. In RFC 6991, this definition excluded
all identifiers starting with any possible combination
of the lowercase or uppercase character sequence 'xml',
as required by YANG 1 defined in RFC 6020. If this type
is used in a YANG 1 context, then this restriction still
applies.";
reference
"RFC 7950: The YANG 1.1 Data Modeling Language
RFC 6991: Common YANG Data Types
RFC 6020: YANG - A Data Modeling Language for the
Network Configuration Protocol (NETCONF)";
}
}
<CODE ENDS>4. Internet Protocol Suite Types ✨
okay so this section is where the good stuff lives, bestie 🌐💖 the "ietf-inet-types" YANG module pulls from a whole squad of RFCs: [RFC0768], [RFC0791], [RFC0952], [RFC1034], [RFC1123], [RFC1930], [RFC2317], [RFC2474], [RFC2780], [RFC2782], [RFC3289], [RFC3305], [RFC3595], [RFC3927], [RFC3986], [RFC4001], [RFC4007], [RFC4271], [RFC4291], [RFC4340], [RFC4592], [RFC5017], [RFC5322], [RFC5890], [RFC5952], [RFC6532], [RFC6793], [RFC8200], [RFC9260], [RFC9293], and [RFC9499]. that's a LOT of main character energy 💅✨
<CODE BEGINS> file "ietf-inet-types@2025-12-22.yang"
module ietf-inet-types {
namespace "urn:ietf:params:xml:ns:yang:ietf-inet-types";
prefix inet;
organization
"IETF Network Modeling (NETMOD) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/netmod/>
WG List: <mailto:netmod@ietf.org>
Editor: Jürgen Schönwälder
<mailto:jschoenwaelder@constructor.university>";
description
"This module contains a collection of generally useful derived
YANG data types for Internet addresses and related things.
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) 2025 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 9911;
see the RFC itself for full legal notices.";
revision 2025-12-22 {
description
"This revision adds the following new data types:
- inet:ip-address-and-prefix
- inet:ipv4-address-and-prefix
- inet:ipv6-address-and-prefix
- inet:protocol-number
- inet:upper-layer-protocol-number
- inet:host-name
- inet:email-address
- inet:ip-address-link-local
- inet:ipv4-address-link-local
- inet:ipv6-address-link-local
The inet:host union was changed to use inet:host-name instead
of inet:domain-name. Several pattern statements have been
improved.";
reference
"RFC 9911: Common YANG Data Types";
}
revision 2013-07-15 {
description
"This revision adds the following new data types:
- inet:ip-address-no-zone
- inet:ipv4-address-no-zone
- inet:ipv6-address-no-zone";
reference
"RFC 6991: Common YANG Data Types";
}
revision 2010-09-24 {
description
"Initial revision.";
reference
"RFC 6021: Common YANG Data Types";
}
/*** collection of types related to protocol fields ***/
typedef ip-version {
type enumeration {
enum unknown {
value 0;
description
"An unknown or unspecified version of the Internet
Protocol.";
}
enum ipv4 {
value 1;
description
"The IPv4 protocol as defined in RFC 791.";
}
enum ipv6 {
value 2;
description
"The IPv6 protocol as defined in RFC 8200.";
}
}
description
"This value represents the version of the Internet Protocol.
In the value set and its semantics, this type is equivalent
to the InetVersion textual convention of the SMIv2.";
reference
"RFC 791: Internet Protocol
RFC 8200: Internet Protocol, Version 6 (IPv6) Specification
RFC 4001: Textual Conventions for Internet Network Addresses";
}
typedef dscp {
type uint8 {
range "0..63";
}
description
"The dscp type represents a Differentiated Services Code Point
that may be used for marking packets in a traffic stream.
In the value set and its semantics, this type is equivalent
to the Dscp textual convention of the SMIv2.";
reference
"RFC 3289: Management Information Base for the Differentiated
Services Architecture
RFC 2474: Definition of the Differentiated Services Field
(DS Field) in the IPv4 and IPv6 Headers
RFC 2780: IANA Allocation Guidelines For Values In
the Internet Protocol and Related Headers";
}
typedef ipv6-flow-label {
type uint32 {
range "0..1048575";
}
description
"The ipv6-flow-label type represents the flow identifier or
Flow Label in an IPv6 packet header that may be used to
discriminate traffic flows.
In the value set and its semantics, this type is equivalent
to the IPv6FlowLabel textual convention of the SMIv2.";
reference
"RFC 3595: Textual Conventions for IPv6 Flow Label
RFC 8200: Internet Protocol, Version 6 (IPv6) Specification";
}
typedef port-number {
type uint16 {
range "0..65535";
}
description
"The port-number type represents a 16-bit port number of an
Internet transport-layer protocol such as UDP, TCP, DCCP, or
SCTP.
Port numbers are assigned by IANA. The current list of
all assignments is available from <https://www.iana.org/>.
Note that the port number value zero is reserved by IANA. In
situations where the value zero does not make sense, it can
be excluded by subtyping the port-number type.
In the value set and its semantics, this type is equivalent
to the InetPortNumber textual convention of the SMIv2.";
reference
"RFC 768: User Datagram Protocol
RFC 9293: Transmission Control Protocol (TCP)
RFC 9260: Stream Control Transmission Protocol
RFC 4340: Datagram Congestion Control Protocol (DCCP)
RFC 4001: Textual Conventions for Internet Network Addresses";
}
typedef protocol-number {
type uint8;
description
"The protocol-number type represents an 8-bit Internet
Protocol number, carried in the 'protocol' field of the
IPv4 header or in the 'next header' field of the IPv6
header.
Protocol numbers are assigned by IANA. The current list of
all assignments is available from <https://www.iana.org/>.";
reference
"RFC 791: Internet Protocol
RFC 8200: Internet Protocol, Version 6 (IPv6) Specification";
}
typedef upper-layer-protocol-number {
type protocol-number;
description
"The upper-layer-protocol-number represents the upper-layer
protocol number carried in an IP packet. For IPv6 packets
with extension headers, this is the protocol number carried
in the last 'next header' field of the chain of IPv6 extension
headers.";
reference
"RFC 791: Internet Protocol
RFC 8200: Internet Protocol, Version 6 (IPv6) Specification";
}
/*** collection of types related to autonomous systems ***/
typedef as-number {
type uint32;
description
"The as-number type represents autonomous system numbers
that identify an Autonomous System (AS). An AS is a set
of routers under a single technical administration, using
an interior gateway protocol and common metrics to route
packets within the AS, and using an exterior gateway
protocol to route packets to other ASes. IANA maintains
the autonomous system number space and has delegated large
parts to the regional registries.
Autonomous system numbers were originally limited to 16
bits. BGP extensions have enlarged the autonomous system
number space to 32 bits. This type therefore uses an uint32
base type without a range restriction in order to support
a larger autonomous system number space. In the value set and its semantics, this type is equivalent
to the InetAutonomousSystemNumber textual convention of
the SMIv2.";
reference
"RFC 1930: Guidelines for creation, selection, and registration
of an Autonomous System (AS)
RFC 4271: A Border Gateway Protocol 4 (BGP-4)
RFC 4001: Textual Conventions for Internet Network Addresses
RFC 6793: BGP Support for Four-Octet Autonomous System (AS)
Number Space";
}
/*** collection of types related to IP addresses and hostnames ***/
typedef ip-address {
type union {
type ipv4-address;
type ipv6-address;
}
description
"The ip-address type represents an IP address and is IP
version neutral. The format of the textual representation
implies the IP version. This type supports scoped addresses
by allowing zone identifiers in the address format.";
reference
"RFC 4007: IPv6 Scoped Address Architecture";
}
typedef ipv4-address {
type string {
pattern
'(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.){3}'
+ '([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])'
+ '(%.+)?';
}
description
"The ipv4-address type represents an IPv4 address in
dotted-quad notation. The IPv4 address may include a zone
index, separated by a % sign. If a system uses zone names
that are not represented in UTF-8, then an implementation
needs to use some mechanism to transform the local name
into UTF-8. The definition of such a mechanism is outside
the scope of this document.
The zone index is used to disambiguate identical address
values. For link-local addresses, the zone index will
typically be the interface index number or the name of an
interface. If the zone index is not present, the default
zone of the device will be used.
The canonical format for the zone index is the numerical
format";
}okay bestie, so this is where the module gets into the IP address types 🌸 ip-address is basically the "I don't care which version, just give me an address" type 💅 it's a union of ipv4-address and ipv6-address, and the text format tells you which one you're looking at. it's giving clean and simple ✨
ipv4-address is the dotted-quad one 🦋 the pattern is a big regex that checks each octet is 0 to 255, with an optional % zone index tacked on the end. the zone index is the thing that tells apart two identical addresses on different links, and if you don't include one, the device's default zone gets used. no cap, the zone-name-to-UTF-8 bit is kind of a plot twist, but the doc says the mechanism for that is out of scope 🙈
typedef ipv6-address {
type string {
pattern '((:|[0-9a-fA-F]{0,4}):)([0-9a-fA-F]{0,4}:){0,5}'
+ '((([0-9a-fA-F]{0,4}:)?(:|[0-9a-fA-F]{0,4}))|'
+ '(((25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.){3}'
+ '(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])))'
+ '(%[A-Za-z0-9][A-Za-z0-9\-\._~/]*)?';
pattern '(([^:]+:){6}(([^:]+:[^:]+)|(.*\..*)))|'
+ '((([^:]+:)*[^:]+)?::(([^:]+:)*[^:]+)?)'
+ '(%.+)?';
}
description
"The ipv6-address type represents an IPv6 address in full,
mixed, shortened, and shortened-mixed notation. The IPv6
address may include a zone index, separated by a % sign.
If a system uses zone names that are not represented in
UTF-8, then an implementation needs to use some mechanism
to transform the local name into UTF-8. The definition of
such a mechanism is outside the scope of this document.
The zone index is used to disambiguate identical address
values. For link-local addresses, the zone index will
typically be the interface index number or the name of an
interface. If the zone index is not present, the default
zone of the device will be used.
The canonical format of IPv6 addresses uses the textual
representation defined in Section 4 of RFC 5952. The
canonical format for the zone index is the numerical
format as described in Section 11.2 of RFC 4007.";
reference
"RFC 4291: IP Version 6 Addressing Architecture
RFC 4007: IPv6 Scoped Address Architecture
RFC 5952: A Recommendation for IPv6 Address Text
Representation";
}and ipv6-address is the big one 😭 it covers full, mixed, shortened, and shortened-mixed notation, which is a lot of looks for one type 💅 the canonical text form is the one from Section 4 of RFC 5952, and the zone index canonical form comes from Section 11.2 of RFC 4007. the regexes are long, but they're just trying to catch every flavour of IPv6 spelling 🌈
typedef ip-address-no-zone {
type union {
type ipv4-address-no-zone;
type ipv6-address-no-zone;
}
description
"The ip-address-no-zone type represents an IP address and is
IP version neutral. The format of the textual representation
implies the IP version. This type does not support scoped
addresses since it does not allow zone identifiers in the
address format.";
reference
"RFC 4007: IPv6 Scoped Address Architecture";
}
typedef ipv4-address-no-zone {
type ipv4-address {
pattern '[0-9\.]*';
}
description
"An IPv4 address without a zone index. This type, derived
from the type ipv4-address, may be used in situations where
the zone is known from the context and no zone index is
needed.";
}
typedef ipv6-address-no-zone {
type ipv6-address {
pattern '[0-9a-fA-F:\.]*';
}
description
"An IPv6 address without a zone index. This type, derived
from the type ipv6-address, may be used in situations where
the zone is known from the context and no zone index is
needed.";
reference
"RFC 4291: IP Version 6 Addressing Architecture
RFC 4007: IPv6 Scoped Address Architecture
RFC 5952: A Recommendation for IPv6 Address Text
Representation";
}
typedef ip-address-link-local {
type union {
type ipv4-address-link-local;
type ipv6-address-link-local;
}
description
"The ip-address-link-local type represents a link-local IP
address and is IP version neutral. The format of the textual
representation implies the IP version.";
}
typedef ipv4-address-link-local {
type ipv4-address {
pattern '169\.254\..*';
}
description
"The ipv4-address-link-local type represents a link-local IPv4
address in the prefix 169.254.0.0/16 as defined in Section 2.1
of RFC 3927.";
reference
"RFC 3927: Dynamic Configuration of IPv4 Link-Local Addresses";
}
typedef ipv6-address-link-local {
type ipv6-address {
pattern '[fF][eE][89aAbB][0-9a-fA-F]:.*';
}
description
"The ipv6-address-link-local type represents a link-local IPv6
address in the prefix fe80::/10 as defined in Section 2.4 of
RFC 4291.";
reference
"RFC 4291: IP Version 6 Addressing Architecture";
}the -no-zone versions are the "the zone is already obvious from context, thanks" types 🎀 they're derived from the zoned ones, and the extra pattern just rules out the % part. ip-address-link-local is the union for link-local stuff, and the two members are pinned to their own prefixes: 169.254.0.0/16 from Section 2.1 of RFC 3927 for IPv4, and fe80::/10 from Section 2.4 of RFC 4291 for IPv6 🧚 it's giving very specific energy, and i'm obsessed.
typedef ip-prefix {
type union {
type ipv4-prefix;
type ipv6-prefix;
}
description
"The ip-prefix type represents an IP prefix and is IP
version neutral. The format of the textual representations
implies the IP version.";
}
typedef ipv4-prefix {
type string {
pattern
'(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.){3}'
+ '([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])'
+ '/(([0-9])|([1-2][0-9])|(3[0-2]))';
}
description
"The ipv4-prefix type represents an IPv4 prefix.
The prefix length is given by the number following the
slash character and must be less than or equal to 32.
A prefix length value of n corresponds to an IP address
mask that has n contiguous 1-bits from the most
significant bit (MSB) and all other bits set to 0.
The canonical format of an IPv4 prefix has all bits of
the IPv4 address set to zero that are not part of the
IPv4 prefix.
The definition of ipv4-prefix does not require that bits
that are not part of the prefix be set to zero. However,
implementations have to return values in canonical format,
which requires non-prefix bits to be set to zero. This means
that 192.0.2.1/24 must be accepted as a valid value, but it
will be converted into the canonical format 192.0.2.0/24.";
}
typedef ipv6-prefix {
type string {
pattern '((:|[0-9a-fA-F]{0,4}):)([0-9a-fA-F]{0,4}:){0,5}'
+ '((([0-9a-fA-F]{0,4}:)?(:|[0-9a-fA-F]{0,4}))|'
+ '(((25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.){3}'
+ '(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])))'
+ '(/(([0-9])|([0-9]{2})|(1[0-1][0-9])|(12[0-8])))';
pattern '(([^:]+:){6}(([^:]+:[^:]+)|(.*\..*)))|'
+ '((([^:]+:)*[^:]+)?::(([^:]+:)*[^:]+)?)'
+ '(/.+)';
}
description
"The ipv6-prefix type represents an IPv6 prefix.
The prefix length is given by the number following the
slash character and must be less than or equal to 128.
A prefix length value of n corresponds to an IP address
mask that has n contiguous 1-bits from the most
significant bit (MSB) and all other bits set to 0.
The canonical format of an IPv6 prefix has all bits of
the IPv6 address set to zero that are not part of the
IPv6 prefix. Furthermore, the IPv6 address is represented
as defined in Section 4 of RFC 5952.
The definition of ipv6-prefix does not require that bits
that are not part of the prefix be set to zero. However,
implementations have to return values in canonical format,
which requires non-prefix bits to be set to zero. This means
that 2001:db8::1/64 must be accepted as a valid value, but it
will be converted into the canonical format 2001:db8::/64.";
reference
"RFC 5952: A Recommendation for IPv6 Address Text
Representation";
}
typedef ip-address-and-prefix {
type union {
type ipv4-address-and-prefix;
type ipv6-address-and-prefix;
}
description
"The ip-address-and-prefix type represents an IP address and
prefix and is IP version neutral. The format of the textual
representations implies the IP version.";
}
typedef ipv4-address-and-prefix {
type string {
pattern
'(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.){3}'
+ '([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])'
+ '/(([0-9])|([1-2][0-9])|(3[0-2]))';
}
description
"The ipv4-address-and-prefix type represents an IPv4
address and an associated IPv4 prefix.
The prefix length is given by the number following the
slash character and must be less than or equal to 32.
A prefix length value of n corresponds to an IP address
mask that has n contiguous 1-bits from the most
significant bit (MSB) and all other bits set to 0.";
}
typedef ipv6-address-and-prefix {
type string {
pattern '((:|[0-9a-fA-F]{0,4}):)([0-9a-fA-F]{0,4}:){0,5}'
+ '((([0-9a-fA-F]{0,4}:)?(:|[0-9a-fA-F]{0,4}))|'
+ '(((25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])\.){3}'
+ '(25[0-5]|2[0-4][0-9]|[01]?[0-9]?[0-9])))'
+ '(/(([0-9])|([0-9]{2})|(1[0-1][0-9])|(12[0-8])))';
pattern '(([^:]+:){6}(([^:]+:[^:]+)|(.*\..*)))|'
+ '((([^:]+:)*[^:]+)?::(([^:]+:)*[^:]+)?)'
+ '(/.+)';
}
description
"The ipv6-address-and-prefix type represents an IPv6
address and an associated IPv6 prefix.
The prefix length is given by the number following the
slash character and must be less than or equal to 128.
A prefix length value of n corresponds to an IP address
mask that has n contiguous 1-bits from the most
significant bit (MSB) and all other bits set to 0. The canonical format requires that the IPv6 address is
represented as defined in Section 4 of RFC 5952.";
reference
"RFC 5952: A Recommendation for IPv6 Address Text
Representation";
}
/*** collection of domain name and URI types ***/
typedef domain-name {
type string {
length "1..253";
pattern
'((([a-zA-Z0-9_]([a-zA-Z0-9\-_]){0,61})?[a-zA-Z0-9]\.)*'
+ '([a-zA-Z0-9_]([a-zA-Z0-9\-_]){0,61})?[a-zA-Z0-9]\.?)'
+ '|\.';
}
description
"The domain-name type represents a DNS domain name. The
name SHOULD be fully qualified whenever possible. This
type does not support wildcards (see RFC 4592) or
classless in-addr.arpa delegations (see RFC 2317).
Internet domain names are only loosely specified. Section
3.5 of RFC 1034 recommends a syntax (modified in Section
2.1 of RFC 1123). The pattern above is intended to allow
for current practice in domain name use and some possible
future expansion. Note that Internet host names have a
stricter syntax (described in RFC 952) than the DNS
recommendations in RFCs 1034 and 1123. Schema nodes
representing host names should use the host-name type
instead of the domain-type.
The encoding of DNS names in the DNS protocol is limited
to 255 characters. Since the encoding consists of labels
prefixed by a length byte and there is a trailing NUL
byte, only 253 characters can appear in the textual dotted
notation.
The description clause of schema nodes using the domain-name
type MUST describe when and how these names are resolved to
IP addresses. Note that the resolution of a domain-name value
may require to query multiple DNS records (e.g., A for IPv4
and AAAA for IPv6). The order of the resolution process and
which DNS record takes precedence can either be defined
explicitly or depend on the configuration of the
resolver.
Domain-name values use the ASCII encoding. Their canonical
format uses lowercase ASCII characters. Internationalized
domain names MUST be A-labels as per RFC 5890.";
reference
"RFC 952: DoD Internet Host Table Specification
RFC 1034: Domain Names - Concepts and Facilities
RFC 1123: Requirements for Internet Hosts -- Application
and Support
RFC 2317: Classless IN-ADDR.ARPA delegation
RFC 2782: A DNS RR for specifying the location of services
(DNS SRV)
RFC 4592: The Role of Wildcards in the Domain Name System
RFC 5890: Internationalized Domain Names in Applications
(IDNA): Definitions and Document Framework
RFC 9499: DNS Terminology";
}
typedef host-name {
type domain-name {
length "2..max";
pattern '[a-zA-Z0-9\-\.]+';
}
description
"The host-name type represents fully qualified host names.
Host names must be at least two characters long (see RFC 952),
and they are restricted to labels consisting of letters,
digits, and hyphens separated by dots (see RFCs 1123 and
952).";
reference
"RFC 952: DoD Internet Host Table Specification
RFC 1123: Requirements for Internet Hosts -- Application
and Support";
}
typedef host {
type union {
type ip-address;
type host-name;
}
description
"The host type represents either an IP address or a fully
qualified host name.";
}
typedef uri {
type string {
pattern '[a-z][a-z0-9+.-]*:.*';
}
description
"The uri type represents a Uniform Resource Identifier
(URI) as defined by the rule 'URI' in RFC 3986.
Objects using the uri type MUST be in ASCII encoding
and MUST be normalized as described in Sections 6.2.1,
6.2.2.1, and 6.2.2.2 of RFC 3986. Characters that can be
represented without using percent-encoding are represented
as characters (without percent-encoding), and all
case-insensitive characters are set to lowercase except
for hexadecimal digits within a percent-encoded triplet,
which are normalized to uppercase as described in
Section 6.2.2.1 of RFC 3986.
The purpose of this normalization is to help provide
unique URIs. Note that this normalization is not
sufficient to provide uniqueness. Two URIs that are
textually distinct after this normalization may still be
equivalent.
Objects using the uri type may restrict the schemes that
they permit. For example, 'data:' and 'urn:' schemes
might not be appropriate.
A zero-length URI is not a valid URI. This can be used to
express 'URI absent' where required.
In the value set and its semantics, this type is equivalent
to the Uri SMIv2 textual convention defined in RFC 5017.";
reference
"RFC 3986: Uniform Resource Identifier (URI): Generic Syntax
RFC 3305: Report from the Joint W3C/IETF URI Planning Interest
Group: Uniform Resource Identifiers (URIs), URLs,
and Uniform Resource Names (URNs): Clarifications
and Recommendations
RFC 5017: MIB Textual Conventions for Uniform Resource
Identifiers (URIs)";
}
typedef email-address {
type string {
pattern '.+@.+';
}
description
"The email-address type represents an internationalized
email address.
The email address format is defined by the addr-spec
ABNF rule in Section 3.4.1 of RFC 5322. This format has
been extended by RFC 6532 to support internationalized
email addresses. Implementations MUST support the
internationalization extensions of RFC 6532. Support
for the obsolete obs-local-part, obs-domain, and
obs-qtext in RFC 5322 is not required.
The domain part may use both A-labels and U-labels
(see RFC 5890). The canonical format of the domain part
uses lowercase characters and U-labels (RFC 5890) where
applicable.";
reference
"RFC 5322: Internet Message Format
RFC 5890: Internationalized Domain Names in Applications
(IDNA): Definitions and Document Framework
RFC 6532: Internationalized Email Headers";
}
}
<CODE ENDS>5. IANA Considerations 📋
okay so IANA's job here is all about the paperwork 🎀 This document reuses the URIs for "ietf-yang-types" and "ietf-inet-types" that already live in the "IETF XML Registry" [RFC3688], so nothing new is being invented for those.
IANA also updated the "YANG Module Names" registry so it points at this RFC instead of [RFC6991] for the "ietf-yang-types" and "ietf-inet-types" modules. Following the format in [RFC6020], the registrations look like this 💖
Name: ietf-yang-types
Namespace: urn:ietf:params:xml:ns:yang:ietf-yang-types
Prefix: yang
Reference: RFC 9911
Name: ietf-inet-types
Namespace: urn:ietf:params:xml:ns:yang:ietf-inet-types
Prefix: inet
Reference: RFC 99116. Security Considerations 💀
ngl this section is short but it's serious 😭 These definitions are just common data types written in the YANG data modeling language. The definitions themselves have no security impact on the Internet, but the way these definitions get used in concrete YANG modules might have one 👀 The security considerations spelled out in the YANG specification [RFC7950] apply to this document as well 🔒
7. References 📚
7.1. 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/info/rfc2119>. - [RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet: Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
<https://www.rfc-editor.org/info/rfc3339>. - [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>. - [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, DOI 10.17487/RFC3986, January 2005,
<https://www.rfc-editor.org/info/rfc3986>. - [RFC4007] Deering, S., Haberman, B., Jinmei, T., Nordmark, E., and B. Zill, "IPv6 Scoped Address Architecture", RFC 4007, DOI 10.17487/RFC4007, March 2005,
<https://www.rfc-editor.org/info/rfc4007>. - [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing Architecture", RFC 4291, DOI 10.17487/RFC4291, February 2006,
<https://www.rfc-editor.org/info/rfc4291>. - [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>. - [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>. - [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>. - [RFC9499] Hoffman, P. and K. Fujiwara, "DNS Terminology", BCP 219, RFC 9499, DOI 10.17487/RFC9499, March 2024,
<https://www.rfc-editor.org/info/rfc9499>. - [RFC9557] Sharma, U. and C. Bormann, "Date and Time on the Internet: Timestamps with Additional Information", RFC 9557, DOI 10.17487/RFC9557, April 2024,
<https://www.rfc-editor.org/info/rfc9557>. - [RFC9562] Davis, K., Peabody, B., and P. Leach, "Universally Unique IDentifiers (UUIDs)", RFC 9562, DOI 10.17487/RFC9562, May 2024,
<https://www.rfc-editor.org/info/rfc9562>. - [XPATH] Clark, J., Ed. and S. DeRose, Ed., "XML Path Language (XPath) Version 1.0", W3C Recommendation, 16 November 1999,
<http://www.w3.org/TR/xpath-10>. - [XSD-TYPES] Peterson, D., Ed., Gao, S., Ed., Malhotra, A., Ed., Sperberg-McQueen, C., Ed., and H. S. Thompson, Ed., "W3C XML Schema Definition Language (XSD) 1.1 Part 2: Datatypes", W3C Recommendation, 5 April 2012,
<https://www.w3.org/TR/xmlschema11-2/>.
7.2. Informative References 📚
okay bestie, these are the extra-credit reads 🧚 the ones that give you context and background but aren't required to build the thing 🎀
- [RFC0768] Postel, J., "User Datagram Protocol", STD 6, RFC 768, DOI 10.17487/RFC0768, August 1980,
<https://www.rfc-editor.org/info/rfc768>. - [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, DOI 10.17487/RFC0791, September 1981,
<https://www.rfc-editor.org/info/rfc791>. - [RFC0952] Harrenstien, K., Stahl, M., and E. Feinler, "DoD Internet host table specification", RFC 952, DOI 10.17487/RFC0952, October 1985,
<https://www.rfc-editor.org/info/rfc952>. - [RFC1034] Mockapetris, P., "Domain names - concepts and facilities", STD 13, RFC 1034, DOI 10.17487/RFC1034, November 1987,
<https://www.rfc-editor.org/info/rfc1034>. - [RFC1123] Braden, R., Ed., "Requirements for Internet Hosts - Application and Support", STD 3, RFC 1123, DOI 10.17487/RFC1123, October 1989,
<https://www.rfc-editor.org/info/rfc1123>. - [RFC1930] Hawkinson, J. and T. Bates, "Guidelines for creation, selection, and registration of an Autonomous System (AS)", BCP 6, RFC 1930, DOI 10.17487/RFC1930, March 1996,
<https://www.rfc-editor.org/info/rfc1930>. - [RFC2317] Eidnes, H., de Groot, G., and P. Vixie, "Classless IN-ADDR.ARPA delegation", BCP 20, RFC 2317, DOI 10.17487/RFC2317, March 1998,
<https://www.rfc-editor.org/info/rfc2317>. - [RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black, "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers", RFC 2474, DOI 10.17487/RFC2474, December 1998,
<https://www.rfc-editor.org/info/rfc2474>. - [RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, DOI 10.17487/RFC2578, April 1999,
<https://www.rfc-editor.org/info/rfc2578>. - [RFC2579] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Textual Conventions for SMIv2", STD 58, RFC 2579, DOI 10.17487/RFC2579, April 1999,
<https://www.rfc-editor.org/info/rfc2579>. - [RFC2780] Bradner, S. and V. Paxson, "IANA Allocation Guidelines For Values In the Internet Protocol and Related Headers", BCP 37, RFC 2780, DOI 10.17487/RFC2780, March 2000,
<https://www.rfc-editor.org/info/rfc2780>. - [RFC2782] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for specifying the location of services (DNS SRV)", RFC 2782, DOI 10.17487/RFC2782, February 2000,
<https://www.rfc-editor.org/info/rfc2782>. - [RFC2856] Bierman, A., McCloghrie, K., and R. Presuhn, "Textual Conventions for Additional High Capacity Data Types", RFC 2856, DOI 10.17487/RFC2856, June 2000,
<https://www.rfc-editor.org/info/rfc2856>. - [RFC3289] Baker, F., Chan, K., and A. Smith, "Management Information Base for the Differentiated Services Architecture", RFC 3289, DOI 10.17487/RFC3289, May 2002,
<https://www.rfc-editor.org/info/rfc3289>. - [RFC3305] Mealling, M., Ed. and R. Denenberg, Ed., "Report from the Joint W3C/IETF URI Planning Interest Group: Uniform Resource Identifiers (URIs), URLs, and Uniform Resource Names (URNs): Clarifications and Recommendations", RFC 3305, DOI 10.17487/RFC3305, August 2002,
<https://www.rfc-editor.org/info/rfc3305>. - [RFC3595] Wijnen, B., "Textual Conventions for IPv6 Flow Label", RFC 3595, DOI 10.17487/RFC3595, September 2003,
<https://www.rfc-editor.org/info/rfc3595>. - [RFC3927] Cheshire, S., Aboba, B., and E. Guttman, "Dynamic Configuration of IPv4 Link-Local Addresses", RFC 3927, DOI 10.17487/RFC3927, May 2005,
<https://www.rfc-editor.org/info/rfc3927>. - [RFC4001] Daniele, M., Haberman, B., Routhier, S., and J. Schoenwaelder, "Textual Conventions for Internet Network Addresses", RFC 4001, DOI 10.17487/RFC4001, February 2005,
<https://www.rfc-editor.org/info/rfc4001>. - [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>. - [RFC4340] Kohler, E., Handley, M., and S. Floyd, "Datagram Congestion Control Protocol (DCCP)", RFC 4340, DOI 10.17487/RFC4340, March 2006,
<https://www.rfc-editor.org/info/rfc4340>. - [RFC4502] Waldbusser, S., "Remote Network Monitoring Management Information Base Version 2", RFC 4502, DOI 10.17487/RFC4502, May 2006,
<https://www.rfc-editor.org/info/rfc4502>. - [RFC4592] Lewis, E., "The Role of Wildcards in the Domain Name System", RFC 4592, DOI 10.17487/RFC4592, July 2006,
<https://www.rfc-editor.org/info/rfc4592>. - [RFC5017] McWalter, D., Ed., "MIB Textual Conventions for Uniform Resource Identifiers (URIs)", RFC 5017, DOI 10.17487/RFC5017, September 2007,
<https://www.rfc-editor.org/info/rfc5017>. - [RFC5131] McWalter, D., Ed., "A MIB Textual Convention for Language Tags", RFC 5131, DOI 10.17487/RFC5131, December 2007,
<https://www.rfc-editor.org/info/rfc5131>. - [RFC5322] Resnick, P., Ed., "Internet Message Format", RFC 5322, DOI 10.17487/RFC5322, October 2008,
<https://www.rfc-editor.org/info/rfc5322>. - [RFC5646] Phillips, A., Ed. and M. Davis, Ed., "Tags for Identifying Languages", BCP 47, RFC 5646, DOI 10.17487/RFC5646, September 2009,
<https://www.rfc-editor.org/info/rfc5646>. - [RFC5890] Klensin, J., "Internationalized Domain Names for Applications (IDNA): Definitions and Document Framework", RFC 5890, DOI 10.17487/RFC5890, August 2010,
<https://www.rfc-editor.org/info/rfc5890>. - [RFC5952] Kawamura, S. and M. Kawashima, "A Recommendation for IPv6 Address Text Representation", RFC 5952, DOI 10.17487/RFC5952, August 2010,
<https://www.rfc-editor.org/info/rfc5952>. - [RFC6021] Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6021, DOI 10.17487/RFC6021, October 2010,
<https://www.rfc-editor.org/info/rfc6021>. - [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>. - [RFC6532] Yang, A., Steele, S., and N. Freed, "Internationalized Email Headers", RFC 6532, DOI 10.17487/RFC6532, February 2012,
<https://www.rfc-editor.org/info/rfc6532>. - [RFC6793] Vohra, Q. and E. Chen, "BGP Support for Four-Octet Autonomous System (AS) Number Space", RFC 6793, DOI 10.17487/RFC6793, December 2012,
<https://www.rfc-editor.org/info/rfc6793>. - [RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>. - [RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", STD 86, RFC 8200, DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>. - [RFC9260] Stewart, R., Tüxen, M., and K. Nielsen, "Stream Control Transmission Protocol", RFC 9260, DOI 10.17487/RFC9260, June 2022,
<https://www.rfc-editor.org/info/rfc9260>. - [RFC9293] Eddy, W., Ed., "Transmission Control Protocol (TCP)", STD 7, RFC 9293, DOI 10.17487/RFC9293, August 2022,
<https://www.rfc-editor.org/info/rfc9293>. - [ISO-8601] ISO/IEC, "Data elements and interchange formats -- Information interchange -- Representation of dates and times", ISO/IEC 8601:2000, December 2008,
<https://www.iso.org/standard/26780.html>. - [ISO-9834-1] ISO/IEC, "Information technology -- Procedures for the operation of object identifier registration authorities -- Part 1: General procedures and top arcs of the international object identifier tree", ISO/IEC 9834-1:2012, 2012,
<https://www.iso.org/standard/58055.html>. - [IEEE-802-2024] IEEE, "IEEE Standard for Local and Metropolitan Area Networks: Overview and Architecture", IEEE Std 802-2024, DOI 10.1109/IEEESTD.2025.10935844, March 2025,
<https://doi.org/10.1109/IEEESTD.2025.10935844>. - [Err4076] RFC Errata, Erratum ID 4076, RFC 6991,
<https://www.rfc-editor.org/errata/eid4076>. - [Err5105] RFC Errata, Erratum ID 5105, RFC 6991,
<https://www.rfc-editor.org/errata/eid5105>.
Acknowledgments 🫶
the people who did the heavy lifting on the original version 💅 (the one published as [RFC6021]) were Andy Bierman, Martin Björklund, Balazs Lengyel, David Partain, and Phil Shafer. absolute legends 👑
a bunch of people also gave super helpful comments on the various draft versions of this doc 🌸 that's Andy Bierman, Martin Björklund, Benoît Claise, Joel M. Halpern, Ladislav Lhotka, Lars-Johan Liman, and Dan Romascanu. thank you all, you're literally the best 💜
Author's Address 💌
Jürgen Schönwälder (editor) Constructor University Email: jschoenwaelder@constructor.university
📦 where this page comes from
- ietf: rfc9911 2025-12
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms