Handling of traffic characteristic deviation for DetNet
draft-han-detnet-tc-dev-handling-00

DetNet                                                            Z. Han
Internet-Draft                                                    C. Liu
Intended status: Standards Track                            China Unicom
Expires: 4 January 2027                                           J. Yan
                                                         ZTE Corporation
                                                                J. Joung
                                                    Sangmyung University
                                                                 R. Pang
                                                            China Unicom
                                                                  X. ZHU
                                                         ZTE Corporation
                                                             3 July 2026

        Handling of traffic characteristic deviation for DetNet
                  draft-han-detnet-tc-dev-handling-00

Abstract

   Deterministic Networking (DetNet) relies on resource reservation to
   guarantee bounded-latency forwarding, yet traffic characteristic
   deviations from microbursts and flow aggregation frequently occur at
   aggregation nodes.  Native handling approaches like direct packet
   discard or best-effort forwarding lead to severe service degradation.

   This document proposes an enhanced traffic characteristic deviation
   solution for DetNet.  This solution specifies two complementary data-
   plane policies: the squeezing policy defers deviated traffic to
   subsequent timeslots within a configurable threshold while preserving
   deterministic attributes to absorb transient bursts; the degrading
   policy reclassifies over-threshold traffic to lower-priority queues
   for graceful handling, avoiding unnecessary packet loss.  These
   policies can be enabled independently or combined, ensuring the
   preferential scheduling and preservation of deterministic service
   traffic under deviation conditions.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

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   Internet-Drafts are draft documents valid for a maximum of six months
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   This Internet-Draft will expire on 4 January 2027.

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   document authors.  All rights reserved.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   5
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   5
   4.  Deviation Condition Detection . . . . . . . . . . . . . . . .   5
   5.  Deviated Traffic Handling Policy  . . . . . . . . . . . . . .   6
     5.1.  Squeezing Policy  . . . . . . . . . . . . . . . . . . . .   7
     5.2.  Degrading Policy  . . . . . . . . . . . . . . . . . . . .   9
     5.3.  Combined Processing Logic . . . . . . . . . . . . . . . .  10
   6.  Traffic Characteristic Deviation Handling Solution  . . . . .  10
     6.1.  Policy Selection and Configuration  . . . . . . . . . . .  10
     6.2.  Deviation Information Reporting . . . . . . . . . . . . .  11
     6.3.  Deviated Traffic Handling Procedure . . . . . . . . . . .  12
   7.  Example . . . . . . . . . . . . . . . . . . . . . . . . . . .  12
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  14
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  14
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     11.1.  Normative References . . . . . . . . . . . . . . . . . .  14
     11.2.  Informative References . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

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1.  Introduction

   DetNet is capable of providing real-time application services with
   deterministic guarantees such as bounded latency, low jitter, and low
   packet loss rate, as per  [RFC8655].  One of the major technologies
   of DetNet is resource allocation, as per [RFC8938], which reserves
   necessary resources for specified DetNet flows to mitigate packet
   loss and jitter caused by network congestion.  The control plane
   orchestrates the paths of DetNet flows to avoid resource conflicts.
   The data plane then transmits DetNet flows based on this
   orchestration result, employing mechanisms like traffic shaping, flow
   admission control, and forwarding information encapsulation to
   maintain the required QoS.

   In the ideal operational model, fine-grained admission control and
   per-hop traffic shaping strictly align incoming traffic with the
   reserved timeslot capacity.  Even at flow aggregation nodes,
   conforming traffic of the same service class will not exceed the pre-
   allocated resource limit, thus delivering strict end-to-end
   deterministic guarantees.

   However, this ideal state is difficult to achieve in practical
   deployments.  Traffic characteristic deviations from the reservation
   baseline arise at multiple layers of the network — from source
   traffic generation, to control plane planning, to data plane
   forwarding — and gradually accumulate and amplify along the path.
   Temporary deviations of traffic characteristics from the reservation
   baseline are inherent operational behaviors rather than network
   faults, originating from multiple sources:

   *  Inherent source traffic deviation forms the root cause.  The
      DetNet resource reservation model typically relies on simplified
      assumptions such as fixed-length packets and uniform arrival
      intervals for traffic planning.  In practice, however,
      deterministic service flows naturally have variable packet lengths
      and uneven arrival times.  The superposition of packet length
      fluctuation and arrival time non-uniformity directly generates
      microbursts at per-hop egress queues, meaning even a single
      properly admitted flow may exceed the reserved capacity of its
      target timeslot at the instantaneous level.

   *  Admission control precision deviation acts as the key transmission
      link.  Current mainstream DetNet admission control mechanisms
      usually operate at second-level time granularity and make
      admission decisions based on the average bandwidth of flow
      profiles.  This coarse granularity fails to capture millisecond-
      level microburst characteristics embedded in traffic.  As a
      result, flows that fully meet the average bandwidth requirement

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      but carry inherent microbursts will be admitted into the network,
      and their instantaneous traffic can easily exhaust the reserved
      timeslot capacity when mapped to egress queues.

   *  Aggregation node superposition deviation serves as the direct
      trigger of severe performance degradation.  Every node on the end-
      to-end DetNet path can act as an aggregation point where multiple
      independent flows share the same egress port and timeslot
      resources.  The microbursts of individual flows may overlap in
      time at the aggregation node, and the superimposed instantaneous
      traffic will far exceed the total reserved capacity of the
      timeslot.  In addition, network control packets such as ARP
      messages usually have higher scheduling priority than
      deterministic service packets, which will preempt reserved
      timeslot resources, further squeeze available forwarding capacity
      for service traffic, and aggravate the risk of queue overflow.

   Current industry solutions to address these challenges have clear
   limitations.  On the control plane, over-provisioning resources based
   on peak traffic and deploying service protection mechanisms can
   offset the impact of bursts to a certain extent, but they rely on a
   large amount of redundant resource reservation, resulting in
   extremely low network resource utilization and weakening the economic
   value of deterministic networking.  In addition, control plane re-
   orchestration and re-admission work on a slow time scale, which
   cannot respond to transient microbursts in real time.  On the data
   plane, existing handling mechanisms for out-of-profile traffic are
   relatively primitive: nodes either directly discard excess packets
   that exceed the timeslot capacity, or buffer them until the next
   available scheduling cycle.  Both approaches will cause severe
   degradation of the QoS of affected flows, and in extreme scenarios,
   their forwarding performance may even be inferior to that of
   traditional Best-Effort (BE) services.Therefore, an enhanced,
   automated data plane mechanism for handling traffic characteristic
   deviations is critical for the practical deployment of DetNet.

   This draft focuses on periodic queuing mechanisms as defined in
   [I-D.ietf-detnet-dataplane-taxonomy], a category of DetNet data plane
   solutions that reserve resources and schedule packets based on
   periodically repeated timeslots and rely on network time
   synchronization.

   This document proposes a complete traffic characteristic deviation
   handling solution for the DetNet data plane, which defines two
   complementary core policies: the squeezing policy and the degrading
   policy.  The two policies can be enabled independently or in
   combination, with configurable activation thresholds and operating
   parameters set by the control plane or network operators.

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   The proposed solution ensures that in-profile deterministic flows
   always receive priority scheduling, while temporarily deviated
   traffic is handled gracefully instead of being discarded directly.
   This mechanism minimizes packet loss caused by microbursts and
   aggregation superposition, realizes smooth degradation of
   deterministic services, and improves the overall operational
   robustness and resource utilization efficiency of DetNet networks.

   The rest of this document is organized as follows: Section 2
   specifies the requirements language; Section 3 defines the
   terminology used in this document; Section 4 describes the deviation
   condition detection mechanism; Section 5 details the design of the
   two handling policies; Section 6 presents the overall solution
   framework and processing procedure; Section 7 provides a deployment
   example; and subsequent sections cover security considerations, IANA
   considerations and references.

2.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

3.  Terminology

   The terminology is defined as[RFC8655].

   The following terminology is used in this document:

   Traffic Characteristic Deviation: A state where the actual traffic
   characteristics (e.g., per-period traffic volume, packet arrival
   rate) of a deterministic flow exceed the range corresponding to the
   reserved resources of the forwarding node, which may cause queue
   overflow under native scheduling logic.

4.  Deviation Condition Detection

   Real-time deviation detection in the data plane serves as the
   foundational trigger for the traffic characteristic deviation
   handling mechanism.  It identifies per-hop forwarding states where
   instantaneous traffic exceeds pre-reserved resource limits, to
   trigger subsequent differentiated handling policies while preserving
   the scheduling priority of in-profile deterministic traffic.

   Per-time-slot reservation parameters delivered by the control plane
   serve as the unified judgment baseline.  For each egress port, the
   control plane pre-configures the maximum authorized forwarding
   capacity (in bits or packets) per timeslot based on end-to-end flow

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   reservations and network-wide slot planning.  This capacity remains
   fixed across scheduling cycles, providing a stable reference for
   deviation judgment.

   Detection runs per packet before enqueuing to the target timeslot:

   1.  Target timeslot mapping: When a DetNet packet arrives, the node
       determines its target egress timeslot based on the timeslot
       identifier in the packet header and per-hop mapping rules
       configured by the control plane.

   2.  Timeslot capacity check: The node checks the current accumulated
       traffic volume within the target timeslot against the reserved
       per-timeslot capacity budget.

   3.  Deviation judgment: If enqueuing the packet does not exceed the
       reserved capacity, the packet is admitted normally.  Otherwise, a
       traffic characteristic deviation condition is confirmed, the
       packet is marked as deviated, and the corresponding handling
       policy is triggered.

   Deviation detection only identifies temporary timeslot resource
   overrun, and does not directly execute default actions such as packet
   discarding.  After detecting a deviation, the node processes deviated
   packets according to pre-configured handling policies (squeezing or
   degrading policy defined in this document).

   This design minimizes packet loss and latency degradation caused by
   transient microbursts, while guaranteeing the deterministic
   scheduling priority of in-profile traffic within the timeslot.

5.  Deviated Traffic Handling Policy

   Two handling policies are defined for deviated traffic, which can be
   enabled independently or in combination with configurable parameters
   set by the control plane:

   *  Squeezing Policy: Temporarily defers deviated packets to the next
      timeslot for transmission, while retaining their original
      scheduling identifiers.

   *  Degrading Policy: Redirects deviated packets to a lower-priority
      forwarding class and modifies their scheduling parameters when the
      accumulation of deviated packets exceeds a predefined threshold.

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   These policies provide flexibility in activation: they can be enabled
   concurrently, individually, or disabled entirely.  If neither policy
   is enabled, the default mechanism, such as discarding the packets or
   treating them as a BE flow, will be utilized.

5.1.  Squeezing Policy

   The squeezing policy provides temporary elastic capacity for timeslot
   allocations to absorb transient microbursts, avoiding immediate
   packet loss caused by short-term traffic deviation.The squeezing
   threshold is a configurable parameter delivered by the control plane,
   which defines the maximum extra traffic volume (measured in bits or
   packets) that a single timeslot can accommodate beyond its reserved
   capacity.  It acts as an elastic buffer zone between standard
   reservation and degrading handling:

   *  It allows temporary traffic overrun within a controlled range,
      preserving the deterministic scheduling attribute of deviated
      packets as much as possible;

   *  Its value can be configured based on total link bandwidth, end-to-
      end service latency tolerance, and statistical characteristics of
      network microbursts.

   When the accumulated traffic volume within a timeslot exceeds the
   reserved capacity but remains below the squeezing threshold, the
   system applies the squeezing policy.  Specifically, the system
   retains the original timeslot identifier in the packet (i.e., tag
   retention), defers the deviated packets to a subsequent timeslot for
   transmission, and records the volume of squeezed traffic.  Downstream
   nodes MAY use the retained tag to identify squeezed packets and
   restore their original scheduling context or reordering state.

   Assume each timeslot allows 4000 bits of forwarding capacity, and the
   squeezing threshold is set to 2000 bits.  Consider a service flow
   where each packet is fixed at 1000 bits: packets 1 to 4 are assigned
   to timeslot 1, and packets 5 to 7 are assigned to timeslot 2.  Due to
   aggregated traffic, assume the current depth of queue 1
   (corresponding to timeslot 1) is 2000 bits.

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       |<----timeslot1---->|<----timeslot2---->|<----timeslot3---->|
       +---------+---------+-------------------+-------------------+
       |/////////|         |                   |                   |
       +---------+---------+-------------------+-------------------+

       packet sequence of the flow
       +----+----+----+----+----+----+----+
       | P7 | P6 | P5 | P4 | P3 | P2 | P1 |     --->
       +----+----+----+----+----+----+----+
       P1 P2 P3 P4 -> target timeslot ： 1
       P5 P6 P7    -> target timeslot ： 2

                                       |
                                       \/
               +---------+----+----+----+----+
       Queue 1 |/////////| P1 | P2 | P3 | P4 |
               +---------+----+----+----+----+
               +----+----+----+
       Queue 2 | P5 | P6 | P7 |
               +----+----+----+

       |-----timeslot1-----|-----timeslot2-----|-----timeslot3-----|
       +---------+----+----+----+----+----+----+----+--------------+
       |/////////| P1 | P2 | P3 | P4 | P5 | P6 | P7 |              |
       +---------+----+----+----+----+----+----+----+--------------+
                                               |<------->|
                                        squeezing threshold

                         Figure 1: Squeezing policy

   Figure 1 illustrates the processing flow: Packets 1 and 2 are
   enqueued into Queue 1, bringing the total occupancy to 4000 bits and
   reaching the reserved capacity.  When packets 3 and 4 arrive, they
   are identified as deviated packets.

   Since the squeezing policy is enabled with a 2000-bit threshold,
   packets 3 and 4 are identified as deviated.  Since the squeezing
   policy is enabled with a 2000-bit threshold, these packets retain
   their original timeslot 1 identifier and are deferred to timeslot 2
   for transmission.  The accumulated traffic volume deferred from
   timeslot 1 to timeslot 2 is 2000 bits.  Subsequently, packets 5, 6,
   and 7 (targeted for timeslot 2) arrive and enter Queue 2.  When Queue
   2 reaches its 4000-bit reserved capacity, packet 7 is marked as
   deviated, enqueued for squeezing, and transmitted in timeslot 3.

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   At aggregation nodes, continuous bursts may lead to successive
   squeezing and trigger a chain reaction.  Without safeguards, packets
   squeezed from one timeslot to the next may accumulate indefinitely,
   undermining deterministic forwarding guarantees.  Two safeguard
   mechanisms are introduced to prevent unbounded accumulation:

   *  Synchronization Threshold Mechanism: Defines a threshold (N) as
      the maximum number of consecutive timeslots permitted to be
      affected by squeezing.  If squeezing occurs over N consecutive
      slots, the current queue must be resynchronized with the timeslot
      schedule to restore consistency and prevent unlimited delay
      accumulation.

   *  Exponential Decay Mechanism: When consecutive squeezing occurs,
      the allowed squeezing threshold decays exponentially.
      Specifically, the first affected timeslot permits a predefined
      squeezing capacity; for each subsequent consecutive timeslot, the
      allowed squeezing capacity is reduced by 50% of the previous slot.
      Decay continues until the permitted capacity falls below the
      minimum packet size, at which point further squeezing is disabled
      and alternative handling (e.g., degrading) is triggered.

|----timeslot1----|----timeslot2----|----timeslot3----|----timeslot4----|
|---------queue1---------|-----queue2------|----queue3-----|---queue4---|
|<--------------------------------------------------------------------->|
                            synchronization threshold

         Figure 2: Illustration of synchronization threshold

|----timeslot1----|----timeslot2----|----timeslot3----|----timeslot4----|
|----------queue1---------|----queue2---|----queue3-----|-----queue4----|
                  |<----->|         |<->|             |-|
                      T              T/2              T/4

        Figure 3: Illustration of Exponential Decay Mechanism

5.2.  Degrading Policy

   The data plane supports the degrading policy and allows for the
   configuration of its parameters.  This policy can be used either
   independently or in conjunction with the squeezing policy.

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   *  Combined deployment with squeezing policy: Degrading is triggered
      for deviated traffic that exceeds the squeezing threshold, serving
      as the second line of defense after squeezing.

   *  Independent deployment: Degrading is applied directly to deviated
      packets that exceed the reserved timeslot capacity, without the
      squeezing phase.

   Degrading is implemented by redirecting deviated packets to a lower-
   priority forwarding class or queue, and updating the corresponding
   scheduling identifier carried in the packet.

5.3.  Combined Processing Logic

   When both squeezing and degrading policies are enabled, the node
   performs hierarchical processing according to the following logic:

   1.  Upon packet arrival, determine whether the packet is deviated by
       checking the target timeslot occupancy against the reserved
       capacity.

   2.  If the accumulated squeezed traffic volume of the target timeslot
       is below the squeezing threshold, and the consecutive squeezing
       count has not reached the synchronization threshold or
       exponential decay limit, apply the squeezing policy to process
       the packet.

   3.  If any of the following conditions are met, immediately trigger
       the degrading policy:

       *  The accumulated squeezed volume exceeds the squeezing
          threshold;

       *  Consecutive squeezing has reached the synchronization
          threshold;

       *  The allowed squeezing capacity after exponential decay is
          insufficient to accommodate the current packet.

6.  Traffic Characteristic Deviation Handling Solution

6.1.  Policy Selection and Configuration

   The following deviation handling policies are defined in this
   document:

   *  Degrading Policy: Process packets according to the degrading
      policy, which includes treating the packets as BE flow.

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   *  Squeezing Policy: This policy provides temporary capacity
      expansion to avoid data loss due to unexpected traffic.

   *  Discarding Policy: Discard deviated packets.

   If neither the squeezing nor degrading policy is enabled, deviated
   packets shall be processed by the default mechanism (e.g., direct
   discarding).When multiple policies are enabled, the processing
   priority shall follow the order of squeezing first, then degrading,
   and finally default fallback mechanisms.  All policy parameters
   (including reserved capacity per timeslot, squeezing threshold,
   synchronization threshold, exponential decay coefficient, degradation
   level, etc.) shall be uniformly delivered by the control plane.

6.2.  Deviation Information Reporting

   Once the data plane automatically handles deviations using the
   squeezing policy or the degrading policy, it should promptly report
   these deviation events to the controller.  This enables the
   controller to perceive detailed insights into the network deviation
   conditions and take appropriate actions, such as re-orchestration,
   flow entry re-configuration, resource expansion.  In addition to
   reporting to the controller, the data plane may also transmit the
   deviation information to the downstream nodes.  This allows
   downstream nodes to adjust their forwarding behavior or restore the
   original parameters of the packets according to the received
   deviation information.  The deviation information reported by the
   data plane includes, but is not limited to:

   *  Basic information: node ID, port ID, etc.

   *  Deviation condition information: flow ID and packet sequence
      number, etc.

   *  Deviated traffic handling policy information:

      -  Policy Type: Specifies the handling policy employed (e.g.,
         squeezing, degrading, or default policies like discarding).

      -  Related parameters:

         o  For squeezing policy: Includes data such as the number of
            squeezed bits and the quantity of squeezed packets.

         o  For the degrading policy: Includes data such as the priority
            levels before and after degrading, and the number of
            degraded packets.

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         o  For default policies: Includes information such as the
            number of discarded packets or treated as BE flows.

6.3.  Deviated Traffic Handling Procedure

   When a node in the data plane receives a DetNet packet, it first
   checks for deviation conditions.  If a deviation is detected, the
   node proceeds to handle the packet.

   1.  Identify Supported Policies: The node determines which deviated
       traffic handling policies are supported locally.

   2.  Policy-based Packet Processing.

       *  No Enhanced Policies Enabled: If the enhanced deviated traffic
          handling policies (i.e., the squeezing policy and the
          degrading policy) are not enabled, the deviated traffic shall
          be processed by the default mechanisms, such as direct
          discarding or treating the packets as Best-Effort (BE) flows.

       *  Single Policy Enabled: Process the deviated packet using the
          enabled policy.

       *  Both Policies Enabled: If both the squeezing policy and
          degrading policy are enabled, the local node first checks
          whether the number of deviated packets exceeds the squeezing
          threshold.  If not, the squeezing policy is applied;
          otherwise, the degrading policy is applied.

   3.  Information Transmission: After processing the deviated packets,
       the node SHOULD send the deviation information to the controller
       and/or the downstream node.

7.  Example

   The following example uses generic terminology for periodic queueing
   mechanisms.  In concrete implementations, these terms map to existing
   mechanisms as follows.  In TCQF[I-D.ietf-detnet-tcqf], the cycle
   corresponds to the logical Timeslot, and the cycle identifier carried
   in the MPLS TC, IPv6 Option, or DSCP field corresponds to the Slot
   Tag. In TQF[I-D.ietf-detnet-packet-timeslot-mechanism], the timeslot
   id carried in the packet header corresponds to the Slot Tag. Both
   mechanisms support deferring excess traffic to a subsequent logical
   timeslot while retaining the original tag for downstream mapping.

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   A DetNet flow is configured with a per-timeslot capacity of 4000
   bits.  Background traffic occupies 3000 bits of Queue 1.  Four
   packets from the flow, each of 1000 bits, arrives at the ingress and
   is placed into Queue 1.

   Processing Procedure:

Queue 1
+------------+----+----+----+
|////////////| P1 | P2 | P3 |
+------------+----+----+----+
 /// : Background traffic (3000 bits, tag TS1)
 P1  : Native, tag TS1
 P2  : Squeezed, tag RETAINED = TS1
 P3  : Squeezed, tag RETAINED = TS1

BE Queue
+-----+
| P4  |
+-----+
 P4  : Degraded

Logical Transmission Timeline

|<---- Timeslot 1  ---->|<---- Timeslot 2  ---->|<---- Timeslot 3  ---->|
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
|/////|/////|/////| P1  | P2  | P3  |     |     |     |     |     |     |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+

BE Traffic (outside deterministic slot structure)
+-----+
| P4  |  (transmitted during available link capacity gap)
+-----+

   Figure 4: Example of Using the Traffic Characteristic Deviation

   1.  Ingress queueing and FIFO scheduling.  Four packets arrive at the
       node.  At the Timeslot 1 boundary, the scheduler processes these
       packets in FIFO order against the logical capacity of Timeslot 1.
       After accounting for 3000 bits of background traffic, only 1000
       bits remain; therefore P1 is scheduled for transmission during
       the Timeslot 1.  The traffic in Timeslot 1 now reaches the per-
       timeslot capacity limit of 4000 bits.

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   2.  Squeezing decision for within-threshold excess with tag
       retention.  P2 and P3 (2000 bits) represent the excess beyond the
       remaining logical capacity of Timeslot 1.  The cumulative excess
       (2000 bits) does not exceed the configured squeeze_threshold.
       The Squeezing Policy is triggered; these packets are retained in
       Queue 1.  They are scheduled for transmission during the Timeslot
       2.

   3.  Degrading decision for beyond-threshold excess.  P4 (1000 bits)
       causes the cumulative excess traffic for Timeslot 1 to reach 3000
       bits, which exceeds the squeeze_threshold.  The Degrading Policy
       is triggered; P4 is removed from Queue 1 and reclassified to the
       BE Queue.

8.  Security Considerations

   TBA

9.  IANA Considerations

   TBA

10.  Acknowledgements

   TBA

11.  References

11.1.  Normative References

   [I-D.ietf-detnet-dataplane-taxonomy]
              Joung, J., Geng, X., Peng, S., and T. T. Eckert,
              "Dataplane Enhancement Taxonomy", Work in Progress,
              Internet-Draft, draft-ietf-detnet-dataplane-taxonomy-05, 8
              January 2026, <https://datatracker.ietf.org/doc/html/
              draft-ietf-detnet-dataplane-taxonomy-05>.

   [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>.

   [RFC8655]  Finn, N., Thubert, P., Varga, B., and J. Farkas,
              "Deterministic Networking Architecture", RFC 8655,
              DOI 10.17487/RFC8655, October 2019,
              <https://www.rfc-editor.org/info/rfc8655>.

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   [RFC8938]  Varga, B., Ed., Farkas, J., Berger, L., Malis, A., and S.
              Bryant, "Deterministic Networking (DetNet) Data Plane
              Framework", RFC 8938, DOI 10.17487/RFC8938, November 2020,
              <https://www.rfc-editor.org/info/rfc8938>.

11.2.  Informative References

   [I-D.ietf-detnet-packet-timeslot-mechanism]
              Peng, S., Liu, P., Basu, K., Liu, A., Yang, D., Peng, G.,
              and J. Zhao, "Timeslot Queueing and Forwarding Mechanism",
              Work in Progress, Internet-Draft, draft-ietf-detnet-
              packet-timeslot-mechanism-01, 27 June 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-detnet-
              packet-timeslot-mechanism-01>.

   [I-D.ietf-detnet-tcqf]
              Eckert, T. T., Li, Y., Bryant, S., Malis, A. G., Ryoo, J.,
              Liu, P., Li, G., and S. Ren, "Deterministic Networking
              (DetNet) Data Plane - Tagged Cyclic Queuing and Forwarding
              (TCQF) for bounded latency with low jitter in large scale
              DetNets", Work in Progress, Internet-Draft, draft-ietf-
              detnet-tcqf-00, 16 January 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-detnet-
              tcqf-00>.

Authors' Addresses

   Zhengxin Han
   China Unicom
   Beijing
   China
   Email: hanzx21@chinaunicom.cn

   Chang Liu
   China Unicom
   Beijing
   China
   Email: liuc131@chinaunicom.cn

   Jinjie Yan
   ZTE Corporation
   China
   Email: yan.jinjie@zte.com.cn

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   Jinoo Joung
   Sangmyung University
   Email: jjoung@smu.ac.kr

   Ran Pang
   China Unicom
   Beijing
   China
   Email: pangran@chinaunicom.cn

   Xiangyang Zhu
   ZTE Corporation
   China
   Email: zhu.xiangyang@zte.com.cn

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