Internet Engineering Task Force (IETF) B. Cheng
Request for Comments: 9892 MIT Lincoln Laboratory
Category: Standards Track D. Wiggins
ISSN: 2070-1721
L. Berger
D. Fedyk, Ed.
LabN Consulting, L.L.C.
November 2025
Dynamic Link Exchange Protocol (DLEP) Traffic Classification Data Item
Abstract
This document defines a new Data Item for the Dynamic Link Exchange
Protocol (DLEP) to support traffic classification. Traffic
classification information identifies traffic flows based on frame/
packet content such as a destination address. The Data Item is
defined in an extensible and reusable fashion. Its use will be
mandated in other documents defining specific DLEP extensions. This
document also introduces DLEP Sub-Data Items; Sub-Data Items are
defined and defines two new Sub-
Data Items to support Diffserv and Ethernet traffic classification.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9892.
Copyright Notice
Copyright (c) 2025 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
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in the Revised BSD License.
Table of Contents
1. Introduction
1.1. Key Words
2. Traffic Classification
2.1. Traffic Classification Data Item
2.1.1. Traffic Classification Sub-Data Item
2.2. Diffserv Traffic Classification Sub-Data Item
2.2.1. Router Receive Processing
2.3. Ethernet Traffic Classification Sub-Data Item
2.3.1. Router Receive Processing
3. Compatibility
4. Security Considerations
5. IANA Considerations
5.1. Data Item Type Values
5.2. Traffic Classification Sub-Data Item Type Values
5.3. Registration Guidance
6. References
6.1. Normative References
6.2. Informative References
Acknowledgments
Authors' Addresses
1. Introduction
The Dynamic Link Exchange Protocol (DLEP) is defined in [RFC8175].
This protocol provides the exchange of link-related control
information between DLEP peers. DLEP peers are comprised of a modem
and a router. DLEP defines a base set of mechanisms as well as
support for possible extensions. DLEP defines Data Items, which are
sets of information that can be reused in DLEP messaging. The DLEP
specification does not include any flow identification beyond DLEP
endpoints, i.e., flows are identified based on their DLEP endpoint.
This document defines DLEP Data Item formats that provide flow
identification on a more granular basis. Specifically, it enables a
router to use traffic flow classification information provided by the
modem to identify traffic flows based on a combination of information
found in a data plane header. (For general background on traffic
classification, see Section 2.3 of [RFC2475].) The Data Item is
structured to allow for the use of the defined traffic classification
information with applications such as credit window control as
specified in [RFC9893]. [RFC9893] provides an example of combining
traffic classification and credit window flow control.
This document defines traffic classification based on a DLEP
destination and flows identified by either Differentiated Services
Code Points (DSCPs) [RFC2475] or IEEE 802.1Q Ethernet Priority Code
Points (PCPs) [IEEE8021Q]. The defined mechanism allows for flows to
be described in a flexible fashion and and, when combined with
applications such as credit window control, allows credit windows to
be (1) shared across traffic sent to multiple DLEP destinations and
as part of multiple flows, flows or (2) used exclusively for traffic sent to
a particular destination and/or belonging to a particular flow. The
extension also supports the "wildcard" matching of any flow (DSCP or
PCP). Traffic classification information is provided such that it
can be readily extended to support other traffic classification
techniques or can be used by extensions that are not related to
credit windows, such as the extension defined in [RFC8651] or even
5-tuple IP flows.
This document defines support for traffic classification using a
single new Data Item (see Section 2.1) for general support. Two support and
defines two new Sub-Data Items are defined to support identification of flows
based on DSCPs and PCPs. PCPs (see Sections 2.2 and 2.3).
1.1. Key Words
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. Traffic Classification
The Traffic Classification Data Item represents a list of flows that
may be used at the same time to provide different service classes for
traffic sent from a router to a modem. The data plane information
used to identify each flow is represented in a separate Sub-Data
Item. The Data Item and Sub-Data Item structures are intended to be
independent of any specific usage of the flow identification, e.g.,
flow control. The Sub-Data Item structure is also intended to allow
for future traffic classification types, e.g., 5-tuple flows. While
the structure of the Data Items is extensible, actual flow
information is expected to be used in an extension-dependent manner.
Support for DSCP and PCP-based flows is defined via individual Sub-
Data Items; see below. Other types of flow identification, e.g.,
based on IP transport-layer protocol and ports, may be defined in the
future via new Sub-Data Items. Note that when extensions supporting
multiple Sub-
Data Sub-Data Item types are negotiated, these types MAY be
combined in a single Data Item.
Each list of flows is identified using a "Traffic Classification
Identifier" or "TID" and is expected to represent a valid combination
of data plane identifiers that may be used at the same time. Each
flow is identified via a "Flow Identifier" or "FID". Each FID is
defined in a Sub-Data Item that carries the data plane identifier or
identifiers used to associate traffic with the flow. A DLEP
destination address is also needed to complete traffic classification
information used in extensions such as flow control. This
information is expected to be provided in an extension-specific
manner. For example, this address can be provided by a modem when it
identifies the traffic classification set in a Destination Up Message
using the Credit Window Association Data Item defined in [RFC9893].
TID and FID values have modem-local scope.
2.1. Traffic Classification Data Item
This section defines the Traffic Classification Data Item. This Data
Item is used by a modem to provide a router with traffic
classification information. When an extension requires the use of
any Data Item, the Data Items, including this Traffic Classification
Data Item, SHOULD be included by a modem in any Session
Initialization Response Message (e.g., see [RFC9893]). Updates to
previously provided traffic classifications or new traffic
classifications MAY be sent by a modem by including the Data Item in
Session Update Messages. More than one Data Item MAY be included in
a message to provide information on multiple traffic classifiers.
The set of traffic classification information provided in the Data
Item is identified using a TID. The actual information related to
data planes that is used in traffic classification is provided in a
variable list of Traffic Classification Sub-Data Items.
The format of the Traffic Classification Data Item is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data Item Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Traffic Class. Identifier (TID)| Num SDIs | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Traffic Classification Sub-Data Item 1 ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Traffic Classification Sub-Data Item n ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Data Item Type:
29
Length:
Variable
Per Section 11.3 of [RFC8175], Length is the number of octets in
the Data Item, excluding the Data Item Type and Length fields.
The length here is limited by the packet data unit (PDU) length
supported. For example, if the packet is limited to 1400 bytes,
then the length MUST NOT exceed this value. If larger packets are
supported, the maximum MUST be adjusted to be smaller than or
equal to the maximum PDU. Multiple messages can be used if there
is more data than will fit in a single TLV.
Traffic Classification Identifier (TID):
A 16-bit unsigned integer identifying a traffic classification
set. There is no restriction on values used by a modem, and there
is no requirement for sequential or ordered values.
Num SDIs:
An 8-bit unsigned integer indicating the number of Traffic
Classification Sub-Data Items included in the Data Item. A value
of zero (0) is allowed and indicates that no traffic should be
matched against this TID.
Reserved:
For the Traffic Classification Data Item, this reserved field is
currently unused. It MUST be set to all zeros for this version of
the Data Item and is currently ignored on reception. This allows
for future extensions of the Data Item if needed.
Traffic Classification Sub-Data Item:
Zero or more Traffic Classification Sub-Data Items of the format
defined in Section 2.1.1 MAY be included. The number MUST match
the value carried in the Num SDIs field.
A router receiving the Traffic Classification Data Item MUST locate
the traffic classification information that is associated with the
TID indicated in each received Data Item. If no associated traffic
classification information is found, the router MUST initialize a new
information set using the values carried in the Data Item. If the
associated traffic classification information is found, the router
MUST replace the corresponding information using the values carried
in the Data Item. In both cases, a router MUST also ensure that any
data plane state (e.g., see [RFC9893]) that is associated with the
TID is updated as needed.
2.1.1. Traffic Classification Sub-Data Item
All Traffic Classification Sub-Data Items share a common format that
is patterned after the standard DLEP Data Item format. See
Section 11.3 of [RFC8175]. There is no requirement on, or meaning
to, Sub-Data Item ordering. Any errors or inconsistencies
encountered in parsing Sub-Data Items are handled in the same fashion
as any other Data Item parsing error encountered in DLEP. See
[RFC8175].
The format of the Traffic Classification Sub-Data Item is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-Data Item Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Value... ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Sub-Data Item Type:
A 16-bit unsigned integer that indicates the type and
corresponding format of the Sub-Data Item's Value field. Sub-Data
Item Types are scoped within the Data Item in which they are
carried, i.e., the Sub-Data Item Type field MUST be used together
with the Traffic Classification Data Item Type to identify the
format of the Sub-Data Item. Traffic Classification Sub-Data Item
Types are managed according to the IANA registry described in
Section 5.2.
Length:
Variable
Per Section 11.3 of [RFC8175], Length is a 16-bit unsigned integer
that is the number of octets in the Sub-Data Item, excluding the
Data Item Type and Length fields. The maximum length is limited on a per Each Sub-Data Item Type. has its own
Length field.
Value:
A field of <Length> octets that contains data specific to a
particular Data Item.
2.2. Diffserv Traffic Classification Sub-Data Item
The Diffserv Traffic Classification Sub-Data Item identifies the set
of DSCPs that should be treated as a single flow, i.e., receive the
same traffic treatment. DSCPs are identified in a list of Diffserv
fields. An implementation that does not support DSCPs and wants the
same traffic treatment for all traffic to a destination or
destinations would indicate 0 DSCPs.
The format of the Diffserv Traffic Classification Sub-Data Item is as
follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-Data Item Type (1) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flow Identifier (FID) | Num DSCPs | DS Field 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| DS Field 2 | ... | DS Field n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Sub-Data Item Type:
Sub-Data Item Type with value one (1) identifies the Diffserv
Traffic Classification Sub-Data Item Type in the format defined in
Section 2.1.1.
Length:
Variable
Length is defined above. For this Sub-Data Item, it is equal to
three (3) octets plus the value of the Num DSCPs field. This
means that the maximum Length base on a FID per DSCP for this TLV
could be 64 times 3 plus one for Num DSCPs plus one DSCPs or 320
octets. The definition can be in multiple Sub-Data Items that are
much smaller than this.
Flow Identifier (FID):
A 16-bit unsigned integer representing the data plane information
carried in the Sub-Data Item that is to be used in identifying a
flow. The value 0xFFFF is reserved and MUST NOT be used in this
field.
Num DSCPs:
An 8-bit unsigned integer indicating the number of DSCPs carried
in the Sub-Data Item. A zero (0) indicates a (wildcard) match
against any DSCP value that does not have an explicit match to a
FID. A typical use of this is mapping any DSCPs that are not
explicitly mapped to a default queue.
DS Field:
Each DS Field is 8 bits long and carries the DSCP field as defined
in [RFC2474].
0 1 2 3 4 5 6 7
+---+---+---+---+---+---+---+---+
| DSCP | MBZ |
+---+---+---+---+---+---+---+---+
DSCP: Differentiated Services Code Point [RFC2474]
MBZ: Must Be Zero - set to zero when transmitted
2.2.1. Router Receive Processing
A router receiving the Traffic Classification Sub-Data Item MUST
validate the information on receipt, prior to using the carried
information, including potentially updating the data behavior as
determined by the extension requiring the use of the Sub-Data Item.
Validation failures MUST be treated as an error as described in
Section 2.1.1.
Once validated, the receiver MUST ensure that each DS Field value is
listed only once across the whole Traffic Classification Data Item.
Note that this check is across the Data Item and not the individual
Sub-Data Item. If the same DS Field value is listed more than once
within the same Traffic Classification Data Item, the Data Item MUST
be treated as an error as described in Section 2.1.1.
2.3. Ethernet Traffic Classification Sub-Data Item
The Ethernet Traffic Classification Sub-Data Item identifies the VLAN
and PCPs that should be treated as a single flow, i.e., receive the
same traffic treatment. Ethernet PCP support is defined as part of
the IEEE 802.1Q tag format [IEEE8021Q] and includes a 3-bit "PCP"
field. The tag format also includes a 12-bit "VLAN Identifier (VID)"
field. PCPs are identified in a list of priority fields. An
implementation that does not support PCPs and wants the same traffic
treatment for all traffic to a destination or destinations would
indicate 0 PCPs. Such an implementation could identify a VLAN to use
per destination.
The format of the Ethernet Traffic Classification Sub-Data Item is as
follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-Data Item Type (2) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flow Identifier (FID) |NumPCPs| VLAN Identifier (VID) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Pri. 1| Pri. 2| ..... | ..... | ..... | Pad |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Sub-Data Item Type:
Sub-Data Item Type with value two (2) identifies the Ethernet
Traffic Classification Sub-Data Item Type in the format defined in
Section 2.1.1.
Length:
Variable
Length is defined above. For this Sub-Data Item, it is equal to
four (4) plus the number of octets needed to accommodate the
number of Priority fields indicated by the NumPCPs field. Note
that as the length is in octets and each Priority field is 4 bits,
the additional total length of this Sub-Data Item is the value carried in 2 octets of Flow
Identifier, plus the NumPCPs field
divided by 2 octets for NumPCPs and rounded VLAN Identifier plus
the number of octets for PCPs. The number of octets for the PCPs
is computed by rounding up NumPCPs to the next higher integer quantity. nearest even value and
dividing by 2. This TLV has a maximum length of 4 plus 8 divided by
2 or 16 8 octets.
Flow Identifier (FID):
A 16-bit unsigned integer representing the data plane information
carried in the Sub-Data Item that is to be used in identifying a
flow. The value 0xFFFF is reserved and MUST NOT be used in this
field.
Num PCPs:
A 4-bit unsigned integer indicating the number of Priority fields
carried in the Sub-Data Item. A zero (0) indicates a (wildcard)
match against any PCP value that does not have an explicit match
to a FID. A typical use of a wildcard is mapping any PCPs that
are not explicitly mapped to a default queue. The maximum number
of PCPs is 8.
VLAN Identifier (VID):
A 12-bit unsigned integer field indicating the VLAN to be used in
traffic classification. A value of zero (0) indicates that the
VID is to be ignored and any VID is to be accepted during traffic
classification. Any explicitly mapped VLANs are matched first.
Any VLANs that do not have a mapping will then map to this default
mapping.
Priority:
Each Priority Field is 4 bits long and indicates a PCP field as
defined in [IEEE8021Q]. Note that zero (0) is a valid value for
either
PCP.
0 1 2 3
+---+---+---+---+
| PCP |MBZ|
+---+---+---+---+
PCP: Priority Code Point [IEEE8021Q]
MBZ: Must Be Zero - set to zero when transmitted
Pad:
A field that is 4 bits long and is included when NumPCPs is an odd
number. This field MUST be set to zero by the sender and MUST be
ignored on receipt.
2.3.1. Router Receive Processing
A router receiving the Traffic Classification Sub-Data Item MUST
validate the information on receipt, prior to using the carried
information, including potentially updating the data behavior as
determined by the extension requiring the use of the Sub-Data Item.
Note that validation can include usage-specific semantics such as
those found in [RFC9893]. Any failures MUST be treated as an error
as described in Section 2.1.1.
After successful validation, the receiver MUST ensure that each
Priority Field value is listed only once across the whole Traffic
Classification Data Item. Note that this check is across the Data
Item and not the individual Sub-Data Items. If the same Priority
Field value is listed more than once within the same Traffic
Classification Data Item, the Data Item MUST be treated as an error
as described in Section 2.1.1.
In cases where both Traffic Classification Sub-Data Item types are
defined, matching on Ethernet information takes precedence. More
specifically, when a packet matches both a DSCP indicated in a
Diffserv Traffic Classification Sub-Data Item (Section 2.2) and a
VID/PCP identified in an Ethernet Traffic Classification Sub-Data
Item (Section 2.3), the TID associated with the matching VLAN/PCP
MUST be used.
3. Compatibility
The formats defined in this document will only be used when
extensions require their use.
The DLEP specification [RFC8175] defines the handling of unexpected
appearances of any Data Items, including those defined in this
document.
4. Security Considerations
This document introduces finer-grained flow identification mechanisms
for DLEP. These mechanisms expose vulnerabilities similar to
existing DLEP messages. An example of a threat to which traffic
classification might be susceptible is where a malicious actor
masquerading as a DLEP peer could inject an alternate Traffic
Classification Data Item, changing the mapping of traffic to queues;
this would in turn cause delay, congestion, or loss in one or more
service classes. Other possible threats are discussed in the
Security Considerations section of [RFC8175] and are also applicable,
but not specific, to traffic classification.
The transport-layer security mechanisms documented in [RFC8175],
along with
some updated references to external documents listed below, the latest versions of [BCP195], [IEEE-802.1AE], and
[IEEE-802.1X] at the time of this writing, can be applied to this
document. Implementations following the "networked deployment" model
described in Section 4 ("Implementation Scenarios") of [RFC8175]
SHOULD refer to [BCP195] for additional details. The Layer 2
security mechanisms documented in [RFC8175] can also, with some
updates, be applied to the mechanisms defined in this document.
Examples of technologies that can be deployed to secure the Layer 2
link include [IEEE-802.1AE] and [IEEE-8802-1X]. [IEEE-802.1X].
5. IANA Considerations
5.1. Data Item Type Values
IANA has assigned the following value from the "Specification
Required" range [RFC8126] in the DLEP "Data Item Type Values"
registry:
+===========+========================+
| Type Code | Description |
+===========+========================+
| 29 | Traffic Classification |
+-----------+------------------------+
Table 1: New Data Item Type Value
5.2. Traffic Classification Sub-Data Item Type Values
IANA has created a new DLEP registry named "Traffic Classification
Sub-Data Item Type Values".
Table 2 shows the registration policies [RFC8126] for the registry:
+=============+=========================+
| Range | Registration Procedures |
+=============+=========================+
| 1-65407 | Specification Required |
+-------------+-------------------------+
| 65408-65534 | Private Use |
+-------------+-------------------------+
Table 2: Registration Policies
Table 3 shows the initial contents of the registry:
+=============+=================================+=============+
| Type Code | Description | Reference |
+=============+=================================+=============+
| 0 | Reserved | RFC 9892 |
+-------------+---------------------------------+-------------+
| 1 | Diffserv Traffic Classification | [RFC2474] |
+-------------+---------------------------------+-------------+
| 2 | Ethernet Traffic Classification | [IEEE8021Q] |
+-------------+---------------------------------+-------------+
| 3-65407 | Unassigned | |
+-------------+---------------------------------+-------------+
| 65408-65534 | Reserved for Private Use | RFC 9892 |
+-------------+---------------------------------+-------------+
| 65535 | Reserved | RFC 9892 |
+-------------+---------------------------------+-------------+
Table 3: Initial Registry Contents
This section provides guidance for registrations in the "Traffic
Classification Sub-Data Item Type Values" registry.
This registry encompasses packet traffic classification, where
standard packet header identifiers in packets or data frames indicate
Quality of Service (QoS) treatment. It includes two specific
registries entries
for widely recognized identifiers used in QoS management for IP and
Ethernet networks. Reserved values are set aside for similar future
identifiers that may emerge to denote QoS treatment. However,
requests for new entries are not expected to be frequent.
Allocations within the registry are subject to the following
requirements:
1. Documentation of the intended use of the requested value, in
compliance with the "Specification Required" policy defined in
[RFC8126].
2. Approval by the designated expert (DE) appointed by the IESG.
The DE must do the following:
* Verify that the requested value is clearly documented and its
purpose and usage are unambiguous.
* Ensure that the proposed value does not conflict with existing
work or ongoing efforts within the IETF.
* Confirm that any specification requesting a code point has
undergone review by the MANET Working Group (or a successor
mailing list designated by the IESG).
* Validate that external specifications requesting code points
are publicly available, are permanently archived, and do not
conflict with active or published IETF work.
* Ensure that the review process is conducted in a timely
manner, with any disputes resolved through consultation with
the appropriate working groups.
5.3. Registration Guidance
This section provides guidance for registrations in the "Traffic
Classification Sub-Data Item Type Values" registry. To simplify
future registrations in DLEP-related registries, it is recommended
that this the guidance in this section apply to all registries within the
"Dynamic Link Exchange Protocol (DLEP) Parameters" registry group. group
that use the "Specification Required" policy [RFC8126]. Future
specifications may point to the guidance in this document.
6. References
6.1. 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>.
[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>.
[RFC8175] Ratliff, S., Jury, S., Satterwhite, D., Taylor, R., and B.
Berry, "Dynamic Link Exchange Protocol (DLEP)", RFC 8175,
DOI 10.17487/RFC8175, June 2017,
<https://www.rfc-editor.org/info/rfc8175>.
6.2. Informative References
[BCP195] Best Current Practice 195,
<https://www.rfc-editor.org/info/bcp195>.
At the time of writing, this BCP comprises the following:
Moriarty, K. and S. Farrell, "Deprecating TLS 1.0 and TLS
1.1", BCP 195, RFC 8996, DOI 10.17487/RFC8996, March 2021,
<https://www.rfc-editor.org/info/rfc8996>.
Sheffer, Y., Saint-Andre, P., and T. Fossati,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 9325, DOI 10.17487/RFC9325, November
2022, <https://www.rfc-editor.org/info/rfc9325>.
[IEEE-802.1AE]
IEEE, "IEEE Standard for Local and metropolitan area
networks-Media Access Control (MAC) Security",
DOI 10.1109/IEEESTD.2018.8585421, IEEE Std 802.1AE-2018,
December 2018,
<https://ieeexplore.ieee.org/document/8585421>.
[IEEE-8802-1X]
[IEEE-802.1X]
IEEE, "IEEE/ISO/IEC "8802-1X-2021 - IEEE/ISO/IEC International Standard-
Telecommunications and exchange between information
technology systems--Requirements for local and
metropolitan area networks--Part 1X:Port-based network
access control", DOI 10.1109/IEEESTD.2021.9650828, IEEE
Std 8802-1X-2021, IEEE-802.1X-2021, December 2021,
<https://ieeexplore.ieee.org/document/9650828>.
[IEEE8021Q]
IEEE, "IEEE Standard for Local and Metropolitan Area
Networks--Bridges and Bridged Networks",
DOI 10.1109/IEEESTD.2022.10004498, IEEE Std 802.1Q-2022,
December 2022,
<https://ieeexplore.ieee.org/document/10004498>.
[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>.
[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/info/rfc2475>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC8651] Cheng, B., Wiggins, D., and L. Berger, Ed., "Dynamic Link
Exchange Protocol (DLEP) Control-Plane-Based Pause
Extension", RFC 8651, DOI 10.17487/RFC8651, October 2019,
<https://www.rfc-editor.org/info/rfc8651>.
[RFC9893] Cheng, B., Wiggins, D., Ratliff, S., Berger, L., and E.
Kinzie, Ed., "Dynamic Link Exchange Protocol (DLEP)
Credit-Based Flow Control Messages and Data Items",
RFC 9893, DOI 10.17487/RFC9893, November 2025,
<https://www.rfc-editor.org/info/rfc9893>.
[RFC9894] Cheng, B., Wiggins, D., Berger, L., and D. Eastlake 3rd,
Ed., "Dynamic Link Exchange Protocol (DLEP) Diffserv Aware
Credit Window Extension", RFC 9894, DOI 10.17487/RFC9894,
November 2025, <https://www.rfc-editor.org/info/rfc9894>.
Acknowledgments
The Sub-Data Item format was inspired by Rick Taylor's "Data Item
Containers". He also proposed the separation of credit windows from
traffic classification at IETF 98. This document was derived from
[RFC9894] as a result of discussions at IETF 101. Many useful
comments were received from contributors to the MANET Working Group,
notably Ronald in 't Velt and David Black.
We had the honor of working too briefly with David Wiggins on this
and related DLEP work. His contribution to the IETF and publication
of the first and definitive open-source DLEP implementation have been
critical to the acceptance of DLEP. We mourn his passing on November
26, 2023. We wish to recognize his guidance, leadership, and
professional excellence. We were fortunate to benefit from his
leadership and friendship. He shall be missed.
Authors' Addresses
Bow-Nan Cheng
MIT Lincoln Laboratory
Massachusetts Institute of Technology
244 Wood Street
Lexington, MA 02421-6426
United States of America
Email: bcheng@ll.mit.edu
David Wiggins
Lou Berger
LabN Consulting, L.L.C.
Email: lberger@labn.net
Don Fedyk (editor)
LabN Consulting, L.L.C.
Email: dfedyk@labn.net