Skip to main content

Application-Responsive Network Framework
draft-yang-rtgwg-arn-framework-09

Document Type Active Internet-Draft (individual)
Authors Feng Yang , Changwang Lin
Last updated 2026-11-01
RFC stream (None)
Intended RFC status (None)
Formats
Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date (None)
Responsible AD (None)
Send notices to (None)
draft-yang-rtgwg-arn-framework-09
RTGWG                                                            F. Yang
Internet-Draft                                              China Mobile
Intended status: Standards Track                                  C. Lin
Expires: 5 May 2027                                 New H3C Technologies
                                                         1 November 2026

                Application-Responsive Network Framework
                   draft-yang-rtgwg-arn-framework-09

Abstract

   With the deployment of increasingly advanced technologies on a large
   scale, such as SRv6[RFC8402] and network slicing, there is a growing
   need to expose these new capabilities to applications.  The current
   practice involves using ACLs to classify packets and then map the
   traffic onto appropriate network resources.  This approach results in
   the application being passively perceived by the network, rather than
   the application actively interfacing with the network.  Furthermore,
   changes in application characteristics necessitate triggering network
   configuration adjustments, making it challenging to deploy at scale.

   The document proposes a new framework called Application Responsive
   Network (ARN), by encapsulating more network functions into ARN ID,
   thus it opens up interfaces to applications.  The vision is to enable
   applications to access network resources like they access an
   operating system.

Status of This Memo

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

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

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 5 May 2027.

Yang & Lin                 Expires 5 May 2027                   [Page 1]
Internet-Draft                ARN Framework                November 2026

Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   4
     1.2.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   4
   2.  Gaps  . . . . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Design Goal . . . . . . . . . . . . . . . . . . . . . . . . .   5
   4.  ARN Framework and Components  . . . . . . . . . . . . . . . .   6
     4.1.  ARN ID  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     4.2.  Application . . . . . . . . . . . . . . . . . . . . . . .   8
     4.3.  User Edge Device  . . . . . . . . . . . . . . . . . . . .   8
       4.3.1.  ARN ID Marking  . . . . . . . . . . . . . . . . . . .   8
     4.4.  Network Edge Device . . . . . . . . . . . . . . . . . . .   9
       4.4.1.  Ingress Processing  . . . . . . . . . . . . . . . . .   9
       4.4.2.  Egress Processing . . . . . . . . . . . . . . . . . .  10
       4.4.3.  Access Control  . . . . . . . . . . . . . . . . . . .  10
       4.4.4.  Cross-domain Aggregation and Mapping  . . . . . . . .  11
       4.4.5.  Service Function Chain Based on ARN . . . . . . . . .  11
       4.4.6.  Rate Limiting . . . . . . . . . . . . . . . . . . . .  12
     4.5.  Controller  . . . . . . . . . . . . . . . . . . . . . . .  12
     4.6.  The Southbound Interface (SBI) of the Controller  . . . .  12
   5.  ARN Encapsulation . . . . . . . . . . . . . . . . . . . . . .  13
     5.1.  Locations for IPv6 ARN  . . . . . . . . . . . . . . . . .  13
     5.2.  Locations for IPv4 ARN  . . . . . . . . . . . . . . . . .  13
   6.  Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . .  13
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  15
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  15
   9.  Normative References  . . . . . . . . . . . . . . . . . . . .  15
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16

Yang & Lin                 Expires 5 May 2027                   [Page 2]
Internet-Draft                ARN Framework                November 2026

1.  Introduction

   With the widespread application of new technologies such as 5G, cloud
   computing, big data, and AI, network traffic patterns are becoming
   increasingly complex and diversified.  Various emerging services have
   higher requirements for QoS parameters such as network latency,
   bandwidth, jitter, and packet loss.

   Networks typically need to prioritize critical services.  For
   example, in office networks, video conferencing requires network
   priority to ensure that video and voice services do not experience
   buffering and excessive delays.  However, the applications used for
   video and voice services may vary in different industries and office
   network scenarios, so it is necessary to identify these applications
   to further ensure the quality of service.

   Some specific services have explicit SLA (Service Level Agreement)
   requirements.  In business scenarios such as autonomous driving,
   industrial control, and remote control, there are clear SLA
   requirements for the network, such as latency not exceeding 50ms and
   jitter not exceeding 1ms.

   In traditional IP networks, ACLs are typically used on critical
   network devices to implement application identification and policy
   configuration.  Based on packet characteristics such as the five-
   tuple, network can provide a guaranteed service for specific users or
   applications.  Different network services have their own ACL matching
   entries and policies, which need to be continuously adjusted as
   services evolve.  Over time, configurations become invalid because
   operators do not revoke or modify them in a timely manner.  This is
   not sufficient for a general solution.

   This article proposes a new framework called Application Responsive
   Network (ARN), which abstracts and represents personalized network
   services based on user demand awareness, provided through ARN Service
   identifiers (ARN IDs).  Network services can be encapsulated by ARN
   IDs, thus it can be called by user.  The vision is to enable
   applications to access network resources like they access an
   operating system.

   The application here can be a network service implemented on a
   gateway or software that can program the ARN ID.

Yang & Lin                 Expires 5 May 2027                   [Page 3]
Internet-Draft                ARN Framework                November 2026

1.1.  Requirements Language

   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.

1.2.  Terminology

   ARN: Application-Responsive Networking

   ACL: Access Control List

   Subscriber: the user who subscribed to a network service, which can
   be represented by an ARN ID

2.  Gaps

   There are still the following key gaps in current network technology:

   Application-aware features.  It is necessary to provide
   differentiated services based on the different services of the same
   user.  For example, video conferencing needs to avoid stuttering or
   screen tearing due to congestion and packet loss to ensure a customer
   experience, while general web browsing services can strive for the
   best.

   Data plane programming capabilities.  Identify and classify user
   application data, and transfer it to the appropriate service-level
   tunnel based on the results.

   Ability to perceive the user experience.  Real-time detection and
   perception of user-level service experience work with intelligent
   routing to ensure service assurance for high-priority services.
   Currently, there is a lack of traffic identification for rapid
   classification and statistical analysis of the user experience of
   this type of traffic.

   Ability to prevent leakage of network services.  The security of the
   access network is relatively poor, and there is a risk of leakage of
   information related to user applications.

Yang & Lin                 Expires 5 May 2027                   [Page 4]
Internet-Draft                ARN Framework                November 2026

3.  Design Goal

   As shown in Figure 1, an ARN intermediate layer is added between the
   application and the network, mapping is accomplished using ARN IDs.
   The ARN ID is a simple number that encapsulates network capabilities
   internally and hides network information externally, thus avoiding
   the exposure of application privacy and facilitating user application
   invocation.

                                  +---+
                       +-----+    | A |    +-------+
                       |App  |--->| R |--->|Network|
                       +-----+    | N |    +-------+
                                  +---+

                  Figure 1: ARN Intermediate Layer Diagram

   ARN Network Design Goals:

   *  Openness of network services.

   One of the design principles of ARN is to open and program network
   capabilities based on the data plane.  By opening programming
   interfaces on the data plane in a software-based manner, applications
   can call network resources like calling an operating system.  In
   today's digital world, user demands for the network far exceed simple
   connectivity functions.  Users expect the network to provide stable,
   high-speed connections to meet diverse application requirements.
   Even for the same type of application, usage requirements may vary
   across different industries and scenarios.  Allowing applications to
   call on network capabilities through data plane programming provides
   corresponding guarantees for different types of packets.

   *  Decoupling of addresses and services.

   Another design principle of ARN is to decouple addresses and
   services.  Traditional network design is based on addresses, managing
   and routing based on destination addresses to determine the
   forwarding services provided by the network.  However, with the
   increasing variety of user applications, relying on addresses to
   carry service levels has made network management increasingly
   complex.  Therefore, it is necessary to manage and optimize the
   network based on the characteristics and requirements of user
   applications, separating addresses from services to provide
   multidimensional forwarding services.

   *  Decoupling of network and applications.

Yang & Lin                 Expires 5 May 2027                   [Page 5]
Internet-Draft                ARN Framework                November 2026

   The third design principle of ARN is to decouple networks and
   applications.  By adding an ARN layer between the network and
   applications, the network does not need to directly perceive the
   applications, thus shielding the diversity of applications and
   preventing direct access to network capabilities.  Through ARN, the
   network and applications can be encapsulated separately, achieving
   application privacy and the concealment of internal network
   information.  At the same time, based on this encapsulation, access
   control can be implemented during the application's network calls,
   realizing an authorization token-based calling mechanism similar to
   software programming.

   *  Unified abstraction of network resources.

   The fourth design principle of ARN is the unified abstraction of
   multiple network resources.  With the development of personalized and
   diversified network services, the network resources used in
   forwarding user packets are becoming increasingly rich, such as
   computing power, network slicing, service chaining, and more.  During
   the use of these network resources, additional identifiers are often
   carried in the packets to determine the mapping relationship between
   users or applications and network resources, or ACLs are used to
   parse and match the feature information in the packet to determine
   the associated network resources.  In the ARN network, multiple
   network resources can be uniformly represented by ARN IDs, reducing
   the complexity of data plane identifiers and simplifying operational
   deployments.

4.  ARN Framework and Components

   ARN Framework, as illustrated in Figure 2, consists of key components
   including User Edge Devices, Network Edge Devices, and network
   controllers at different levels.

                      +--------------------------+
                      |       Controller         |
                      +-+----------+----------+--+
                        |          |          |
                        |SBI       |  SBI     |
           +----+    +--+--+    +--+--+    +--+--+    +-------+
           |App |--->|User |--->|     |    |     |    |       |
           +----+    |Edge |    | Net |    | Net |    | Cloud |
                     +-----+    | work|--->| work|--->|       |
           +----+               | Edge|    | Edge|    |Service|
           |App |-------------->|     |    |     |    |       |
           +----+               +-----+    +-----+    +-------+
                      Access         Backbone

Yang & Lin                 Expires 5 May 2027                   [Page 6]
Internet-Draft                ARN Framework                November 2026

                   Figure 2: Framework and Key Components

4.1.  ARN ID

   The ARN ID represents the application's invocation of network
   capabilities and/or the network's ability to be open to the
   application.  It needs to be implemented on both User Edge Devices
   and Network Edge Devices.

   The ARN ID also represents a contractual relationship, and therefore
   requires lifecycle management of ARN ID, e.g., revocation, loss
   reporting, replacing, aging, and deferring operations.

   The ARN ID can be generated by the controller based on the user
   service subscription information and network service information, and
   the generated ARN ID will be configured to both User Edge Devices and
   Network Edge Devices.  User service subscription information may
   include user information, e.g. PPPoE, and application information,
   e.g. 5 tuple.  The network service information can be pre-planned
   network paths, e.g. SR policies.

   A method of allocating ARN ID by PPPoE mechanism is as follows:

   Firstly, the User Edge Device such as BRAS sends the configuration
   request used to query ARN ID which characterizes a service subscribed
   by a user.  The request includes at least one or more of protocol
   type, protocol length, and service id based on the pre-set protocol.
   The network device connected to the user device receives the request
   according to the pre-set protocol(e.g.  NCP) and allocates the
   configuration with ARN ID to the user device based on the request.
   According to pre-set service information including service type and
   identification information of user device, network device determines
   the service type of user device.  Furthermore, it determines ARN ID
   of the user device based on the said service type information.

   Secondly, the user device sends the configuration request with ARN ID
   to confirm that the ARN ID is correct.  The network device receives
   the message and sends the confirmation message to the user device
   based on the confirmation request, which is used to characterize
   whether ARN ID is correct.  When the ARN ID in the configuration
   request sent from the user device matches the ARN ID in the
   configuration information sent from the network device, the network
   device sends the confirmation message characterizing the accuracy of
   ARN ID which is allocated to the user device.

Yang & Lin                 Expires 5 May 2027                   [Page 7]
Internet-Draft                ARN Framework                November 2026

4.2.  Application

   User applications require networks to provide differentiated
   services, especially those based on SR technology.  There are two
   scenarios.

   The first scenario is that the user's application supports ARN.  By
   delivering ARN ID to user, user can encapsulate ARN ID for certain
   application to achieve differentiated services.  In this case, the
   application needs to insert the ARN ID into the extension header of
   the IPv6 packet.

   The second scenario is that the user's application does not support
   ARN.  In this case, network service provider needs to deliver ARN ID
   to User Edge Device and map application traffic to the ARN ID to
   achieve differentiated services.

4.3.  User Edge Device

   The User Edge Devices are responsible for accessing the user
   applications and are the boundary of the access network.  The access
   network will not be a part of SRv6 or MPLS domains.

   The User Edge Device obtains the ARN ID sent by the controller, where
   the ARN ID is assigned by the controller to the User Edge Device
   based on user information, application information, and network
   service information.  The ARN ID generated by the controller includes
   user information, and the User Edge Device inserts this ARN ID into
   IPv6 packet and transmits it to Network Edge Device.

4.3.1.  ARN ID Marking

   ARN ID will be applied on a User Edge Device, and include the
   following operations:

   *  Obtain the ARN ID;

   *  The ARN ID represents the invocation relationship of the
      application to network capabilities and/or the network
      capabilities exposed to the application;

   *  Based on the ARN ID to mark the original IP packet, generate IPv6
      packet accordingly, and transmit the IPv6 packet.

   The ARN ID SHOULD be encapsulated into the extension header of the
   IPv6 packet, which will be explained in detail in Section 5.  In this
   case, an extra IPv6 header is needed.

Yang & Lin                 Expires 5 May 2027                   [Page 8]
Internet-Draft                ARN Framework                November 2026

   Optionally, marking the original IPv6 packet based on the ARN ID
   includes either inserting the ARN ID into an extension header of the
   original IPv6 packet, or inserting the ARN ID into the Source Address
   field of the original IPv6 packet header.

4.4.  Network Edge Device

   The Network Edge Devices aggregate the traffic from access network,
   which is the edge of the backbone network.  The backbone network runs
   SRv6 and MPLS.

   The Network Edge Device is the boundary of the backbone network,
   which is the starting point of network service, e.g. tunnels such as
   SR Policies with various characteristics.  Of course, SR Policies are
   pre-planned by the network operator.

   When ARN is applied to Network Edge Devices, the ARN performs the
   following primary functions:

   *  Receives packet generated by the User Edge Device that carry an
      ARN ID; the packet is created by the User Edge Device by marking
      the original IP packet based on the obtained ARN ID;

   *  The ARN ID represents the invocation relationship of the
      application to network capabilities and/or the network
      capabilities exposed to the application.

   If the Network Edge Device is a PE, it is desired that VPN services
   are carried by multiple SRv6 Policies with different color.  In this
   case, the ARN ID in the packet from user can be used to select the
   appropriate SRv6 Policy.

4.4.1.  Ingress Processing

   The processing of ARN occurs on the edge devices at the boundary of
   the ARN domain.  Upon receiving an IP packet containing an ARN ID,
   the Network Edge Device must:

   *Parse the IP packet to extract the ARN ID;

   *Validate the legitimacy of the ARN ID against a pre-configured ARN
   ID validation table, which stores predefined mappings between user
   information and ARN IDs;

   *If the validation result confirms that the user's ARN ID is valid,
   map the ARN-tagged IP packet to the corresponding network path or
   network slice based on that ARN ID.

Yang & Lin                 Expires 5 May 2027                   [Page 9]
Internet-Draft                ARN Framework                November 2026

   When external packets with ARN ID enter the ARN domain, they will be
   mapped to SRv6 Policy or slice through the ARN Ingress mapping table.
   At this point, the ARN ID can be considered as the Color of the data
   plane, corresponding to the Color of the SRv6 Policy.

4.4.2.  Egress Processing

   When packets leave the ARN domain, the SRv6 Policy can also be mapped
   to the ARN ID of the next domain.  Like ingress processing, there
   will be an egress mapping table.  The mapping operation is quite
   similar to VLAN translation.

4.4.3.  Access Control

   Before trusting the incoming ARN ID of the packet outside limited
   domain, verification is necessary.

   The user facing interface should support configuration option to
   enable or disable the ARN function.  When a Network Edge Device
   receives a packet carrying an ARN ID, if the ARN function on the
   interface is enabled, it should perform ARN related access control
   and forwarding processing on the packet.  If the ARN function on the
   interface is disabled, the ARN ID in the packet should be ignored,
   that is, the processing associated with ARN should be skipped.

   The verification of the source information and the ARN ID is based on
   a pre-configured ARN ingress mapping table, which keeps records of
   the correspondence between the source information and the ARN ID,
   including:

   *  The source information of the packet, which represents the
      subscriber.

   *  The subscribed ARN ID.

   *  The mapping relationship between the ARN ID and network services
      (such as SR Policy[RFC9256]/Flex Algo).

   The received packet contains source information of the packet, such
   as source address, PPPoE, tunnel, interface and other information,
   which is used to identify subscribers.

Yang & Lin                 Expires 5 May 2027                  [Page 10]
Internet-Draft                ARN Framework                November 2026

   When the ARN function is enabled on the interface, the network edge
   device MUST verify the source information and the ARN ID of the
   packet.  If the packet passes verification, the Network Edge Device
   SHALL map the IPv6 packet to the corresponding network path or
   network slice based on that ARN ID.  If the packet verification
   fails, the interface SHOULD skip the ARN ID related processing of the
   packet.

   If the verification is failed, the following actions may be
   performed:

   *  Ignore the ARN ID carried in the packet or discard the IPv6
      packet;

   *  Map the IPv6 packet to the default path or slice associated with
      packets that do not carry an ARN ID.

4.4.4.  Cross-domain Aggregation and Mapping

   The edge network device in the current domain(Domain A) receives the
   packet carrying the ARN ID 1 which is sent by another edge network
   device, and queries the ARN ID 2 which is mapped to ARN ID 1 in the
   target domain from a preset cross-domain mapping relationship.  Then
   it replaces ARN ID 1 with ARN ID 2 to obtain the new packet and sends
   it to the device in target domain(Domain B).

   The preset cross-domain mapping relationship is established as
   follows: after receiving the ARN ID assigned in the current domain
   and the ARN ID assigned in the target domain, the service
   orchestration system establishes a mapping relationship between the
   two ARN IDs for the network path required by the same application,
   and then delivers it to the edge network device via the domain
   controller of the current domain.

   The ARN ID 1 configured in flow label, Destination Option
   Header(DOH), or Hop-by-Hop Option Header(HBH) of the packet is
   changed to the ARN ID 2 to generate the modified packet and then the
   modified packet is sent to the target domain.

4.4.5.  Service Function Chain Based on ARN

   In the SRv6 SFC scenario, the traditional solution of SRv6 SFC
   requires allocating SIDs for each service (including each SF or each
   user) and advertising relevant routes, leading to high complexity in
   the number of SIDs and routes, which makes it impossible to truly
   implement.  The ARN-based approach can greatly simplify this SID and
   route allocation mechanism.  It only uses ARN IDs to integrate
   network and service capabilities, while SIDs are only used as network

Yang & Lin                 Expires 5 May 2027                  [Page 11]
Internet-Draft                ARN Framework                November 2026

   path identifiers, reducing the coupling with services.

   The gateway device of SFC receives and parses the SID in the service
   flow.  According to the instruction information of the SID function,
   the IPv6 packet in the service flow and the corresponding extension
   header are parsed to obtain the application and network capability
   identifier(that is ARN ID), which is used to indicate the service
   function SF.  Furthermore, the outgoing interface or IP address to
   the next-hop node corresponding to the SF indicated by the ARN ID is
   obtained.  According to the association table sent by the controller
   device (or statically configured), the outgoing interface or IP
   address to the next-hop node corresponding to the SF indicated by ARN
   ID is searched, including the association between SF and destination
   IP address or between SF and virtual interface.

4.4.6.  Rate Limiting

   Imposes traffic limits on specific ARN IDs, typically deployed at the
   Network Edge Device.

4.5.  Controller

   The controller generates ARN IDs in the way mentioned in Section 4.1.
   The controller also configures User Edge Devices and Network Edge
   Devices, and manages the lifecycle of ARN IDs.

   The controller will send the ARN ID and the application
   characteristics corresponding to the ARN ID to the User Edge Device.

   The controller MAY generate ARN ingress mapping table and send to
   Network Edge Device, which is used for access control.  Alternately,
   the ARN ingress mapping table MAY also be populated by routing
   protocols.  At the same time, the controller will send the path
   information and the preset correspondence of the ARN ID to the
   Network Edge Device, and the path information can be SR Policy.

   A single controller can be centrally used, or multiple controllers
   can be utilized to collectively fulfill the functions across various
   stages of the network.

4.6.  The Southbound Interface (SBI) of the Controller

   The ARN ID and ARN service policies are transmitted from the
   controller to the relevant network devices for execution through this
   interface.  Candidate protocols for this interface include PCEP, BGP,
   and YANG-based protocols (NETCONF/RESTCONF).

Yang & Lin                 Expires 5 May 2027                  [Page 12]
Internet-Draft                ARN Framework                November 2026

5.  ARN Encapsulation

5.1.  Locations for IPv6 ARN

   ARN carries ARN ID option including ARN ID through the extension of
   the IPv6 data plane.  The location for carrying this information is
   within the IPv6 Destination Options Header (DOH) or IPv6 Hop-by-Hop
   Options Header (HBH).

   The ARN ID option can be carried in the IPv6 Destination Options
   Header.  By using the DOH Options Header, the information carried can
   be read by the destination node but would not normally be seen by
   other nodes along the path.

   The ARN ID option can be carried in the IPv6 Hop-by-Hop Options
   Header.  By using the HBH Options Header, the information carried can
   be read by every node along the path.

      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Next Header  |  Hdr Ext Len  | Option Type   | Opt Data Len  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                           ARN ID                              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

     Option Type: 8 Bits, ARN option, value to be allocated
     ARN ID: 32 Bits

                          Figure 3: ARN ID Option

5.2.  Locations for IPv4 ARN

   TBD.

6.  Use Cases

Yang & Lin                 Expires 5 May 2027                  [Page 13]
Internet-Draft                ARN Framework                November 2026

                         +---------------------+
                         | Network Controller  |
                         +----+------------+---+
                              |            |
                          +---+--+      +--+---+     +-------+
                          |      |   A  |      |     |       |
            +-----+       | Back +------+ Back |     |  DC   |
            | HGW |------>| bone |   B  | bone |     | Cloud |
            +-----+       | Edge +------+ Edge +-----+       |
              User        |      |   C  |      |     |       |
                          | Bras +------+      |     |Service|
                          +------+      +------+     +-------+

                         Figure 4: Use case of ARN

   This is a typical network where users access the network through a
   Bras server, then via the backbone network, and finally access the
   data center cloud services.  Functions implemented by each device:

   Home Gate Way(HGW): Acts as the User Edge Device, ARN ID can be
   directly marked by it based on the services user has purchased and
   flow characteristics of the application.

   Bras: Provides functions such as access control based on Service-ID,
   path mapping, service aggregation, and rate limiting.  If the
   incoming datagram carries an ARN ID, and the receiving interface has
   turned on ARN.  The legitimacy of the ARN ID can be verified.  If the
   ARN ID does not belong to the user, the verification will fail, and
   the ARN ID will be cleared or the entire datagram will be discarded.
   Otherwise, it will perform Path Mapping based on incoming ARN ID.

   Network Controller: Configure user information and ARN ID mappings
   for HGW.  Configuring access control, path mapping, and rate limiting
   based on ARN ID for Bras.

   Cloud Services: Provides specific application services.

   Based on the different types of ARN services purchased by users, when
   mapping paths in the domain for forwarding user traffic, three
   network paths can be chosen according to the rules deployed by the
   controller to meet the users' network requirements.  As different
   applications may have varying network demands, the five-tuple of the
   datagrams is mapped to corresponding ARN IDs for different network
   services.  This enables the network's entry router to select
   different network paths based on the different ARN IDs:

   *  Network Path A: Network path characterized by high bandwidth

Yang & Lin                 Expires 5 May 2027                  [Page 14]
Internet-Draft                ARN Framework                November 2026

   *  Network Path B: Network path characterized by low latency

   *  Network Path C: Network path characterized by low packet loss

   If a user's different applications have varying network requirements,
   the user can directly include the corresponding network service's ARN
   ID in the transmitted datagrams.  This allows the network's entry
   router to select different network paths based on the different ARN
   IDs.

7.  IANA Considerations

   Option type number in the header should be allocated.

8.  Security Considerations

   This document will not affect the security of the Internet.

9.  Normative References

   [RFC8402]  Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
              Decraene, B., Litkowski, S., and R. Shakir, "Segment
              Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
              July 2018, <https://www.rfc-editor.org/rfc/rfc8402>.

   [RFC9256]  Filsfils, C., Talaulikar, K., Ed., Voyer, D., Bogdanov,
              A., and P. Mattes, "Segment Routing Policy Architecture",
              RFC 9256, DOI 10.17487/RFC9256, July 2022,
              <https://www.rfc-editor.org/rfc/rfc9256>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/rfc/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.

Contributors

   Joel Halpern
   Email: jmh@joelhalpern.com

   Many thanks to Joel Halpern for reviewing the ARN ID mapping
   mechanism.

Yang & Lin                 Expires 5 May 2027                  [Page 15]
Internet-Draft                ARN Framework                November 2026

Authors' Addresses

   Feng Yang
   China Mobile
   China
   Email: yangfeng@chinamobile.com

   Changwang Lin
   New H3C Technologies
   China
   Email: linchangwang.04414@h3c.com

Yang & Lin                 Expires 5 May 2027                  [Page 16]