ETSI GS F5G 031 V1.1.1 (2025-12)

Fifth Generation Fixed Network (F5G); Intelligent Management for PON based Industrial Network

DGS/F5G-0031

General Information

• Status: Not Published
• Technical Committee: F5G - Fifth Generation Fixed Network
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Due Date: 12-Dec-2025
• Completion Date: 15-Dec-2025

Standards Content (Sample)

GROUP SPECIFICATION
Fifth Generation Fixed Network (F5G);
Intelligent Management for PON based Industrial Network
Disclaimer
The present document has been produced and approved by the Fifth Generation Fixed Network (F5G) ETSI Industry
Specification Group (ISG) and represents the views of those members who participated in this ISG.
It does not necessarily represent the views of the entire ETSI membership.

2 ETSI GS F5G 031 V1.1.1 (2025-12)

Reference
DGS/F5G-0031
Keywords
F5G, management, telemetry, YANG

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3 ETSI GS F5G 031 V1.1.1 (2025-12)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
1 Scope . 6
2 References . 6
2.1 Normative references . 6
2.2 Informative references . 7
3 Definition of terms, symbols and abbreviations . 7
3.1 Terms . 7
3.2 Symbols . 7
3.3 Abbreviations . 7
4 Intelligent Management Architecture . 8
4.1 Hierarchical Architecture Overview . 8
4.1.1 Management Architecture for PON based Industrial Network . 8
4.1.2 Management Protocols and Functions . 9
4.1.2.1 NETCONF . 9
4.1.2.2 Telemetry . 9
4.1.2.3 MQTT . 10
4.1.2.4 Device Access Security . 10
4.2 Intelligent Management Processes . 10
5 Key Functions for PON Management in Industrial Network . 11
5.1 Fundamentals . 11
5.1.1 Deterministic Network . 11
5.1.2 Protection Management . 12
5.1.3 Energy Saving . 13
5.1.3.1 OLT PON Port Switching . 13
5.1.3.2 ONU PON Port Switching . 13
5.1.4 East to West Traffic . 14
5.2 Basic Operations . 15
5.2.1 Deterministic Latency Control . 15
5.2.2 Protection Management . 16
5.2.2.1 Single Protection Configuration . 16
5.2.2.2 Dual-Parenting Protection Configuration . 16
5.2.2.3 Typical Protection Scenarios . 17
5.2.2.3.1 Overview . 17
5.2.2.3.2 Type B Protection . 17
5.2.2.3.3 Type C Protection . 17
5.2.2.3.4 Type D Protection. 18
5.2.2.3.5 Dual-Parent Protection . 19
5.2.2.4 Functional Behaviour of Protection Groups . 20
5.2.3 Energy Saving . 21
5.2.3.1 ONU Traffic Prediction . 21
5.2.3.2 OLT and ONU PON Port Mode Switching . 21
5.2.4 East to West Service Configuration . 22
6 Key Functions for Network Latency Measurement in Industrial Network . 22
6.1 Fundamentals . 22
6.1.1 Out-of-band Network Information Telemetry . 22
6.1.2 In-band Network Information Telemetry . 23
6.2 Basic Operations . 25
6.2.1 Out-of-band Network Information Telemetry . 25
6.2.1.1 Port Role Configuration . 25
6.2.1.2 Out-of-band Measurement Flow Initialization . 25
6.2.1.3 Measure-instances Initialization . 25
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4 ETSI GS F5G 031 V1.1.1 (2025-12)
6.2.2 In-band Network Information Telemetry . 25
6.2.2.1 Global Parameters Configuration . 25
6.2.2.2 Port Role Configuration . 25
6.2.2.3 Static-instances Initialization . 25
6.2.2.4 Flow Filtering for In-band Measurement . 25
7 F5G YANG Modules for PON Management in Industrial Network . 26
7.1 Overviews. 26
7.2 Relationship with Other YANG Models . 26
7.3 Modules and Sub-modules . 26
7.3.1 Deterministic Network Models . 26
7.3.1.1 Module an-xpon-deterministic-control.yang . 26
7.3.2 Protection Management Models . 27
7.3.2.1 Module an-pon-protection-group.yang . 27
7.3.2.2 Module an-protection-group.yang . 27
7.3.3 East to West Traffic Models . 28
7.3.3.1 Module an-l2-forwarding-policies.yang . 28
8 F5G Telemetry Models for Latency Measurement in Industrial Network . 29
8.1 Overviews. 29
8.2 Relationship with Other Telemetry Models . 29
8.3 Latency Measurement . 29
8.3.1 ONIT Models . 29
8.3.1.1 Module an-onu-uni.yang . 29
8.3.1.2 Module an-onit.yang . 29
8.3.1.3 Module an-onit.proto. 30
8.3.2 INIT Models . 30
8.3.2.1 Module an-init-common.yang . 30
8.3.2.2 Module an-init.yang . 30
8.3.2.3 Module an-init.proto . 31
History . 33

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5 ETSI GS F5G 031 V1.1.1 (2025-12)
Intellectual Property Rights
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Foreword
This Group Specification (GS) has been produced by ETSI Industry Specification Group (ISG) Fifth Generation Fixed
Network (F5G).
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.

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6 ETSI GS F5G 031 V1.1.1 (2025-12)
1 Scope
The present document defines the Intelligent Management for PON based industrial network. The present document
primarily focuses on new management requirements in PON based industrial network which have not been addressed so
far. The present document identifies and specifies new features and solutions to enhance the efficiency and intelligence
of PON based industrial network management.
2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found in the
ETSI docbox.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are necessary for the application of the present document.
[1] IETF RFC 7950: "The YANG 1.1 Data Modeling Language".
[2] ETSI GS F5G 022 (V1.1.1): "Fifth Generation Fixed Network (F5G); Specification for PON based
Industrial Network".
[3] ETSI GS F5G 011 (V1.1.1): "Fifth Generation Fixed Network (F5G); Telemetry Framework and
Requirements for Access Network".
[4] IETF RFC 6241: "Network Configuration Protocol (NETCONF)".
[5] ISO/IEC 20922:2016: "Message Queuing Telemetry Transport". .
[6] IETF RFC 6022: "YANG Module for NETCONF Monitoring".
[7] BBF TR-383: "Common YANG Modules for Access Networks".
[8] BBF TR-385: "ITU-T PON YANG Modules".
[9] Recommendation ITU-T G.984.1: "Gigabit-capable Passive Optical Networks (G-PON): General
characteristics".
[10] IETF RFC 7223: "A YANG Data Model for Interface Management".
[11] BBF TR-069: "CPE WAN Management Protocol".
[12] IETF RFC 7371: "A YANG Data Model for System Management".
[13] IETF RFC 8348: "A YANG Data Model for Hardware Management".
[14] IETF RFC 8648: "A YANG Data Model for Alarm Management".
[15] ETSI GS F5G 016 (V1.1.1): "Fifth Generation Fixed Network (F5G); Data Models of Telemetry
for Access Network".
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2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents may be useful in implementing an ETSI deliverable or add to the reader's
understanding, but are not required for conformance to the present document.
[i.1] ETSI GS F5G 004 (V1.1.1): "Fifth Generation Fixed Network (F5G); F5G Network Architecture".
[i.2] Recommendation ITU-T G.984.3 (2014): "Gigabit-capable passive optical networks (G-PON):
Transmission convergence layer specification".
[i.3] Recommendation ITU-T G.9804.2 (2021): "Higher speed passive optical networks - Common
transmission convergence layer specification".
[i.4] Recommendation ITU-T G.Sup51 (06/17): "Passive optical network protection considerations".
3 Definition of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the terms given in ETSI GS F5G 004 [i.1] and the following apply:
aging time: validity period of a measurement instance, after which the measurement instance automatically becomes
inactive
container: interior data node that has no value of its own but contains a list of child nodes in the YANG schema tree
IETF RFC 7950 [1]
3.2 Symbols
Void.
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
BBF Broadband-Forum
CPE Customer Premises Equipment
ID Identifier
IETF Internet Engineering Task Force
INIT In-band Network Information Telemetry
IP Internet Protocol
ITU-T International Telecommunication Union - Telecommunication Standardization Sector
MAC Media Access Control
MQTT Message Queuing Telemetry Transport
MTU Maximum Transmission Unit
NBI Northbound Interface
NETCONF Network Configuration protocol
OAM Operation Administration and Maintenance
OLT Optical Line Terminal
ONIT Out-of-band Network Information Telemetry
OMCI ONU Management and Control Interface
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ONU Optical Network Unit
PMS PON Management System
PON Passive Optical Network
P-ONU Primary Optical Network Unit
SDN Software Defined Network
SNMP Simple Network Management Protocol
SVM Support Vector Machine
TC Transmission Convergence
T-CONT Transmission Container
TR Technical Report
UNI User Network Interface
VLAN Virtual Local Area Network
WAN Wide Area Network
WTR Wait-To-Restore
XGEM 10-Gigabit Encapsulation Method
YANG Yet Another Next Generation data modelling language
4 Intelligent Management Architecture
4.1 Hierarchical Architecture Overview
4.1.1 Management Architecture for PON based Industrial Network
ETSI GS F5G 022 [2] defines the industrial PON system architecture. The PMS is an instance of management plane in
industrial PON system. It provides equipment access, network monitoring, efficient configuration, secure access
control, high reliability, and network latency and service quality assurance capabilities.

Figure 1: SDN Architecture of PMS in PON based Industrial Network
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Figure 1 illustrates the SDN architecture of PMS in PON based Industrial Network. It is structured to efficiently handle
the complexities and unique requirements of industrial environments. The management architecture can be visualized as
a multi-layered structure comprising several key components:
• Device Management Layer:
- Network Monitoring: The management system in the PON based Industrial Network should support
network monitoring, including monitoring the operational status of devices, network link status, and
network service status. The operational status of devices includes the status of OLTs and ONUs. The
network link status includes optical link metrics and optical module status. The network service status
includes port and service rates, bandwidth utilization and service latency, including the latency of both
north-south and east west traffic.
- Device Access: The PON based Industrial Network management system should support connecting to
devices via a local internal network. These devices include OLTs and ONUs, and the management
protocols include, but are not limited to, SNMP, NETCONF/YANG, and MQTT. Additionally, for the
security of the industrial PON network, the PMS should perform security authentication of devices
before establishing a complete connection to ensure device access authorization.
• Service Layer: The core of the service layer is the SDN-based control service, which enables the expansion of
new industrial applications, intelligent management process, and industry service value to be created. Typical
industrial services include intelligent energy saving, experience measurement, service optimization, and
resource scheduling. The service layer uses the YANG model fundamentals to obtain the collection of the
configuration operation descriptions required to implement the service functions. It should construct a
tree-structured process model of service functions based on the execution sequence of the corresponding
configuration operations using each configuration operation description. The execution sequence is based on
the service process specification in relevant standard documents. By traversing the process model in
accordance with such execution sequence, the service layer implements these service functions. Additionally,
by performing a backward traversal of the process model, the service layer should support the rollback of
configurations. This rollback capability ensures that any changes can be reversed safely, reducing the risk of
errors and maintaining system stability.
• Control and Orchestration Layer: The Control and Orchestration Layer integrates service layer interfaces
and provides common northbound interfaces for other platforms to use. Its goal is to make capabilities and
data in PON based Industrial Network accessible, allowing different management systems to work together
easily. This layer helps streamline network management and improve service delivery efficiency by offering
consistent service configuration workflows.
4.1.2 Management Protocols and Functions
4.1.2.1 NETCONF
The NETCONF [4] protocol defines a simple mechanism through which a network device shall be managed. The
NETCONF Controller is a part of the PMS which shall use the NETCONF protocol to initiate a session to the access
device. The YANG models are developed for specifying NETCONF operations and define the capabilities that the
access device may implement. The NETCONF controller should set up a standard YANG file library in advance by
using the various equipment types and the corresponding standard YANG model files for each equipment type. The
NETCONF controller should search the standard YANG file library (e.g. IETF, BBF, ETSI) based on the equipment
type to determine the type of the access device and its corresponding YANG model files.
4.1.2.2 Telemetry
Telemetry [3] protocol defines a network performance collection mechanism. Telemetry system is a part of the PMS. It
shall use this protocol to receive high-precise network performance data. The Telemetry data models are developed for
specifying the device implementation.
Note that in ETSI GS F5G 016 [15], it has developed a couple of Telemetry data models. In the present document, it
augments a few network latency measurement features for PON based Industrial Network.
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4.1.2.3 MQTT
MQTT [5] is a lightweight messaging protocol. It may be used for the management and information collection of
P-ONUs and standard ONUs in industrial PON environments. The detailed technical requirements and functions are for
further study.
4.1.2.4 Device Access Security
For the security of industrial PON networks, the PMS should verify the device that is managed. The access device
should support NETCONF Monitoring [6] feature and the NETCONF controller should retrieve the YANG model files
sent by the access device. The NETCONF controller parses the received YANG model files and based on the parsing
result, it allows the access device to get online and be managed by the PMS if the parsed YANG model files meet at
least one of the following conditions. Otherwise, it prevents the devices from getting online in the system:
• The YANG model files contain the standard YANG model files for the equipment type of the access device.
• The YANG model files include all the nodes of the standard YANG model files, and the included tree node of
the standard YANG model files is consistent with its tree node hierarchy.
4.2 Intelligent Management Processes
The intelligent management process is an important driver for autonomous network in PON based industrial network. It
should provide an automatic mechanism to optimize the network performance and fault troubleshooting without human
intervenes.
In the following a general set of technical aspects of the intelligent management process in the service layer of PMS in
PON based Industrial Network are described:
• Standard configuration process model:
The required configuration protocol shall be NETCONF [4]. The required configuration operations for
industrial service functions are determined by the YANG models of the corresponding service functions.
Based on the hierarchical architecture of tree nodes of YANG model files for the PON equipment in industrial
networks, the path information for the standard configuration process model of the required configuration
operations is determined. The configuration operations and path information are collected as the set of
configuration operation descriptions required for each service function.
• Data collection and storage:
Telemetry technology provides data monitoring and reporting of network performance, device status, and
service performance for PON based in Industrial Networks. The service layer should support data collection,
data storage, and data presence to users in real-time. The stored data should enable performance monitoring,
fault analysis, and operational optimization.
• Intelligent service management:
Based on the collected optical link status, proactive fault management should be supported to identify and
eliminate potential risks in advance. According to the collected network status, appropriate network
optimization strategies and flexible resource scheduling should be performed to achieve agile service creation
and configuration.
With the introduction of intelligent management process, the following efficiency is improved for the PON based
Industrial Network and creates a greener and smarter network:
• Operational efficiency improvement: Applications are measurable, ensuring guaranteed service quality.
Network failures shall be detected remotely.
• Energy efficiency improvement: Reducing the total energy consumption across the infrastructure in PON
based Industrial Network.
• Bandwidth efficiency improvement: Increase the number of value-added services.
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5 Key Functions for PON Management in Industrial
Network
5.1 Fundamentals
5.1.1 Deterministic Network
The ETSI ISG F5G an-xpon-deterministic-control YANG Module focuses on the deterministic network management in
a PON based Industrial Network. It contains several augmentations to ietf-interfaces [10] and bbf-xpon [8] models
related to the basic PON management. The presence of such augmentations indicates the configuration nodes for
deterministic network latency control in the PON system:
• accurate-maximum-differential-distance: Defines the maximum allowed differential distance for the closest
ONU and the furthest ONU from this OLT PON port, ensuring latency synchronization.
• onu-discovery-switch: It controls the enable/disable switch for ONU discovery of this OLT PON port
channel. It is enabled by default. When disable is configured, the OLT PON port channel shall not discover the
newly launched ONU.
• quiet-window-mode: It defines how the OLT PON channel termination [9] sorts the T-CONTs [i.2] and how
the quiet window is set depending the influence state on how the quiet window influences the ONU burst
transmission window during the service transmission cycle in a PON system [i.3]. There are three quiet
window modes:
1) standard mode: OLT PON channel termination opens a quiet window to temporarily suppress upstream
transmission by the in-service ONUs during serial number acquisition or ranging [9]. Once the quiet
window is activated, it influences the ONU burst transmission and it introduces an additional delay.
2) time-sensitive mode: Sorting of time sensitive T-CONTs is prior to ONU discovery. The quiet window
shall not affect the ONU's burst transmission window. The start point of the quiet windows is associates
with the burst transmission window. Once there is enough idle timeslot for a quiet window, which means
that the quiet window opening has no effect on the burst transmission window. The OLT PON channel
termination should open a quiet window in the service transmission cycle and set the specific start point
of the quiet window, which is later than all burst transmission window during the service transmission
cycle. Once there are not enough idle timeslots for a quiet window, which means that the quiet window
opening has effect on the burst transmission window, the OLT PON channel termination shall cancel the
quiet window opening.
3) best-effort mode: ONU discovery is prior to sorting of the time sensitive T-CONTs. If there are not
enough idle timeslots for a quiet window, the time sensitive burst transmission windows are affected and
causes increased network latency.
• dba-calculation-cycle: Defines single-frame burst count capability for this PON channel. The count of the
single-frame burst of the ONU T-CONT under this PON channel shall not exceed its dba-calculation-cycle.
• timeslot-reserve-switch: The enable/disable switch for managing the reservation for offline ONU time slots
in the PON system. It is used to maintain the network stability.
• time-sensitive: It indicates whether the T-CONT is time-sensitive for low latency service. The OLT should
support the transmission of the sorted services in one upstream frame period which serves as a transmission
resource in the PON system as shown in Figure 2. For the low latency network, the start point of the quiet
window in one upstream frame period shall be later than all the uplink transmission windows. The OLT PON
channel termination [9] should support sorting the uplink transmission windows of the ONU services
containing both low latency services and non-low latency services according to the quiet window mode, which
is user/administrator predefined sequencing logic. The starting point of all uplink transmission windows for
low latency services should be adjusted before the non-low latency services. The sequence of all the uplink
transmission windows for low latency services is sorted by its window size from the largest to the smallest.
• dba-distribution-cycle: Defines the count of single-frame bursts of the T-CONT of a particular ONU.
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• onu-distance: Defines the distance between the ONU and the OLT, used for calculating and adjusting the
network latency.
• last-quiet-window-failed: Track when the last time an OLT PON channel termination fails to open the quiet
window, which is for troubleshoot.

Figure 2: Upstream Frame Period (TC frame) in PON system
Furthermore, to achieve deterministic network latency in service transmission, the OLT should support the control of
the timeslot allocation mechanism in the XGEM partition of the TC frame. When the OLT receives the pending service
data, it should set the current timeslot in the XGEM partition of the TC frame as the candidate matching timeslot. The
OLT should execute the following procedures repeatedly to determine the target timeslot for the received pending
service data based on the multiple timeslots of the XGEM partition in the TC frame and encapsulate the received
pending service data into the target timeslot:
1) The availability of the candidate matching slot should be determined according to the packet type of the
pending service data;
2) If the candidate matching timeslot is unavailable, the next timeslot should be selected as the new candidate
matching timeslot. This process should continue until an available candidate matching timeslot is found, and
such available timeslot should be determined as the target timeslot for the received pending service data.
Within each TC frame, the time occupied by the XGEM partition contains multiple timeslots, and each
timeslot supports encapsulation of service data corresponding to its predefined packet type.
3) If the target timeslot has not yet started at the current time, the pending service data should be temporarily
stored in the buffer corresponding to the target timeslot. Once the target timeslot begins, the pending service
data should be encapsulated into the target timeslot for upstream transmission.
5.1.2 Protection Management
The ETSI ISG F5G Protection YANG Modules focus on the protection management in PON based Industrial Network,
including protection switching, uplink port protection, PON port protection [i.4], optical link protection and ONU
protection. In addition to this, dual-parents protection and protection status monitoring are also supported. Different
protection members and working modes are configured in the protection group, and industrial users or OAM personnel
control traffic switching manually or automatically to ensure high network stability. The presence of such nodes and
items indicates the protection Management in PON based Industrial Network:
• protection-groups:
- Each protection group is uniquely identified by a group-id. The protection group contains a description
field and a definition of the type of protection object, which is an ethernet port, an aggregation group, a
PON port, or an ONU.
- protection-object: different types of protection members are defined, including ethernet ports,
aggregation groups, PON ports, or ONU devices.
- Work mode: includes three modes:
1) time-delay: 1:1 architecture, primary and standby switching, which is for PON Type B [9]
protection;
2) port-state: 1:1 architecture, primary and standby enabled, but only the primary member carries
services, which is for PON Type C [9] or Type D [9] protection;
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13 ETSI GS F5G 031 V1.1.1 (2025-12)
3) load-balance: 1+1 architecture, the primary and standby members carry services at the same time,
which is for PON Type C or Type D protection.
• dual-parenting-flag: indicates whether the protection group supports dual-parenting. The dual-parenting
protection group switches traffic between different network elements to improve stability.
• Recovery and protection functions:
- revertive (Recovery mode): controls whether traffic is automatically switched back to the primary
member after the fault is recovered.
- wtr-time (Protection group recovery time): a waiting period when recovery mode is enabled to avoid
frequent switching after the work path has recovered.
• Protection member: each protection group contains two protection members, one of which is a working
member and the other is a protecting member. Traffic switching is performed based on member status and
configuration.
• Operation functions: includes commands such as freeze, lockout, forced-switch, manual-switch, which are
used to manually or automatically manage the switching of traffic in the protection group under different
states.
• Uplink monitoring: uplink monitoring is used to monitor the connection status between the protection group
and the uplink port to ensure the availability of the uplink.
• Type B protection: Type B protection is specific to OLT PON protection architectures and be configured for
standard Type B networks or vendor specified Type B networks.
• dual-parenting protection: defines the dual-parenting protection group pairs of nodes and members. This
includes the handshake status of the pair-end node and communication keys, to ensure communication
synchronization between dual-parenting members. These configurations enable traffic protection and
switching between different OLTs to ensure service reliability.
5.1.3 Energy Saving
5.1.3.1 OLT PON Port Switching
The BBF TR-385 [8] YANG modules define the channel pairs interface management. Operators shall use
enable/disable in 'ietf-interfaces' [10] for OLT PON port switching.
5.1.3.2 ONU PON Port Switching
There are two scenarios for ONU PON port channel switching management as shown in Figures 3 and 4.
• In scenarios where the ONU is managed indirectly by the OLT, the PMS sends the ONU PON channel control
commands to the OLT, and the OLT translates the commands into OMCI commands to the ONU. The
requirements and parameters are for further study.
• In scenarios where the PMS directly manages the ONU, the PMS sends ONU PON channel control commands
containing PON channel control strategy directly to the ONU. The protocol includes MQTT, BBF
TR-069 [11] and the ONU should have corresponding modules to receive the commands. The modules should
control the ONU PON port channel according to the channel control strategy in the received control
commands. The requirements for the modules and command parameters are for further study.
ETSI
14 ETSI GS F5G 031 V1.1.1 (2025-12)

Figure 3: ONUs Managed Indirectly by OLTs

Figure 4: PMS Directly Manages ONUs
5.1.4 East to West Traffic
The ETSI ISG F5G l2-forwarding YANG Module focuses on the network interoperability for two following scenarios
as shown in Figures 5 and 6. It contains two augmentations to bbf-l2-forwarding [7] related to the layer 2 forwarding.
The presence of such augmentations indicates the configuration nodes of forwarding policy profile instances and
pointing the profile to the corresponding forwarder instance:
• forwarding-policy-profiles: This augmentation introduces the ability to define multiple forwarding-policy-
profiles. The profiles are designed to be flexible and extensible for the future, allowing users to apply various
forwarding policies based on specific requirements, such as VLANs. Within each profile, parameters like the
forwarding-horizon are configured to control east to west traffic forwarding for specified VLAN-IDs.
• forwarder policy: This augmentation extends the forwarder configuration by associating a forwarding-policy-
profile with each forwarder instance. T
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