IP Network Slicing
Author : Jian Wang, Zhibo Hu, Jie Dong
Copyright
Author:
Jian Wang, Zhibo Hu, Jie Dong
Key Contributors:
Wei Shao, Ruiqiang Lu
Release Date:
2021-09-15
Issue:
01
Copyright © Huawei Technologies Co., Ltd. 2021. All rights reserved.
No part of this document may be reproduced or transmitted in any form or by any means without prior written
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and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.
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Notice
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Preface
Author Introduction
Jian Wang: As a senior datacom documentation engineer in Huawei, he has long
been engaged in developing technical documentation for key features of
datacom products. He has also been responsible for reviewing and delivering
guidance documents for key products and once worked as the editor-in-chief of
VNF Product Knowledge Overview and Special Topic - IP FPM.
Zhibo Hu: Senior technical expert of Huawei Data Communication Protocol
Design Dept. He joined Huawei in 2007 and has taken the lead in Segment
Routing over IPv6 (SRv6) research and standardization, involving SRv6,
Generalized SRv6 (G-SRv6), slice ID-based network slicing solution, and more. He
has published more than 50 individual patents and more than 10 drafts in the
Internet Engineering Task Force (IETF). He is the deputy editor-in-chief of SRv6
Network Programming: Ushering in a New Era of IP Networks.
Jie Dong: Principal engineer and standards representative in Huawei Data
Communication Standard & Patent Dept. He joined Huawei in 2007 and has
taken the lead in the research and standardization of routing protocols, Virtual
Private Network (VPN), SRv6, 5G transport, and other fields. He has published 12
IETF RFC documents and co-authored SRv6 Network Programming: Ushering in a
New Era of IP Networks.
i
Preface
About This Book
This book describes the background of IP network slicing, explores its technical
value and solution, and presents successful deployment cases. This book aims to
help you understand the value and technical architecture of IP network slicing.
Intended Audience
This book is intended for network planning engineers, network design engineers,
mid- and senior-level managers at service providers and enterprises, and readers
who want to understand cutting-edge IP network technologies. Because network
slicing involves many network concepts, readers of this book should be familiar
with IP network basics, such as the IP network architecture, Flexible Algorithm
(Flex-Algo), and resource reservation technologies.
ii
Preface
Acknowledgments
In writing and publishing this book, we received extensive help and support from
both inside and outside Huawei. We sincerely thank Jinzhu Chen, Meng Zuo,
Zhenbin Li, Zhiqiang Du, Zhaokun Ding, Dawei Fan, Chenxi Wang, Wenjun Meng,
Tao Han, Hongkun Li, Fenghua Zhao, Yue Liu, and other leaders and experts
from Huawei Data Communication Product Line for their guidance and support.
Our thanks also go to Hui Tian, Shujun Han, Danni Ma, and other experts from
China Academy of Information and Communications Technology, who not only
provided valuable technical guidance but also carefully reviewed the book.
This book focuses on the most cutting-edge IPv6 technologies, which are still
evolving and deepening. While we have made significant efforts to ensure
accuracy, there might be omissions or deficiencies in the book. Your comments
and feedback are warmly welcomed.
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Preface
Table of Contents
Chapter 1 Overview of Network Slicing ......................................................................... 1
Chapter 2 Background of Network Slicing .................................................................... 3
2.1 Emerging Diversified Services....................................................................... 3
2.2 Challenges Facing IP Networks.................................................................... 7
2.3 Background of Network Slicing ................................................................. 11
Chapter 3 Benefits of Network Slicing ........................................................................ 13
3.1 Resource and Security Isolation ................................................................. 13
3.2 Differentiated SLA Assurance ..................................................................... 15
3.3 Extremely High Reliability Assurance ...................................................... 16
3.4 Flexible Topology Connection Customization ....................................... 17
3.5 Automated Slice Management .................................................................. 19
Chapter 4 Architecture of Network Slicing ................................................................ 21
Chapter 5 Network Slicing Solutions ........................................................................... 26
5.1 Overview of Network Slicing Solutions ................................................... 26
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Table of Contents
5.2 Affinity-based Network Slicing Solution ................................................. 28
5.3 Slice ID-based Network Slicing Solution ................................................. 32
5.4 Comparison Between Network Slicing Solutions ................................. 39
Chapter 6 Suggestions on Network Slicing Deployment ....................................... 41
6.1 Deploying Network Slicing Based on Networking Scenarios ........... 41
6.2 Resource Reservation Based on Service Requirements ...................... 46
Chapter 7 Successful Applications of Network Slicing ........................................... 51
7.1 Smart Healthcare — Slice-based Healthcare Private Network ..... 51
7.2 Smart Policing — Slice-based Public Security Private Network .... 54
7.3 Smart Port — Slice-based Port Private Network ................................ 57
7.4 Smart Grid — Slice-based Power Grid Private Network .................. 60
Chapter 8 Technical Prospects of Network Slicing .................................................. 64
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Table of Contents
Chapter 1
Overview of Network Slicing
Communication networks are often compared to transport systems, in which
data packets are "vehicles" and networks are "roads." These roads become more
and more congested as the number of vehicles increases. To alleviate congestion,
transportation departments plan lanes and manage traffic based on vehicle
types and operation modes. For example, they usually set dedicated lanes for
Bus Rapid Transit (BRT) and non-motorized vehicles. This is also the case with a
network. The number of connections and the amount of data traffic will increase
rapidly in the evolution from connecting everyone to connecting everything.
Without intervention, a network will become more and more congested and
complex, eventually affecting the service performance of the network. Similar to
the transport system, communication networks also require "lane" division and
traffic management, both of which can be achieved using network slicing.
Network slicing provides multiple logical networks (slices) on the same shared
network infrastructure. Each slice serves a specific service type or industry user,
as shown in Figure 1-1, and can flexibly define its logical topology, Service Level
Agreement (SLA) requirements, reliability, and security level to meet
differentiated requirements of different services, industries, or users.
1
Overview of Network Slicing
Figure 1-1 Network slicing
Carriers can use network slicing to meet differentiated network connection and
service quality requirements of different service types or industry users. This not
only eliminates the cost of constructing multiple private networks, but also
provides highly flexible network services that can be scheduled and allocated on
demand based on service requirements, thereby improving carriers' network
value and monetization capability and facilitating the digital transformation of
various industries.
In a broad sense, network slicing is a complete set of solutions, involving the
radio access network, IP network, and mobile core network. This book mainly
describes network slicing on the IP network.
2
Overview of Network Slicing
Chapter 2
Background of Network
Slicing
Abstract
Network slicing is designed to meet emerging differentiated service
requirements in the 5G and cloud era. Within only a few years of being
proposed, network slicing has been successfully applied in various
industries. This chapter analyzes the challenges facing IP networks from
the perspective of diversified services in the 5G and cloud era, and
describes the background of network slicing.
2.1 Emerging Diversified Services
In terms of network connections, 5G changes their attributes while the cloud
changes their scope. The development of new 5G services poses more
requirements on network connections, such as stricter SLA assurance and ultralow latency. In addition, the development of various cloud services has brought
greater flexibility to service access locations. And some cloud services (such as
telco cloud) further break the boundary between physical and virtual network
3
Background of Network Slicing
devices, integrating services and transport networks. Such changes have
reshaped the scope of network connections. With the emergence of diversified
services in the 5G and cloud era, different users pose various service quality
requirements on networks.
5G
In the 5G era, the characteristics of mobile data, massive device connections, and
various vertical industry services vary significantly. Services such as mobile
communication, environment monitoring, smart home, smart agriculture, and
smart metering require huge numbers of device connections and frequent
transmission of many small packets. Other services such as live streaming, video
uploading, and mobile healthcare require higher transmission rates, while
Internet of Vehicles (IoV), smart grid, and industrial control services require
millisecond-level latency and near-100% reliability. As such, 5G networks must
provide capabilities such as massive access, ultra-low latency, and ultra-high
reliability to meet diversified service requirements of users and vertical industries.
Based on the main scenarios and service requirements of mobile Internet and the
Internet of Things (IoT), the International Telecommunication Union (ITU) has
defined three typical 5G application scenarios, as shown in Figure 2-1.
4
Background of Network Slicing
Figure 2-1 Typical application scenarios in the 5G era

Enhanced Mobile Broadband (eMBB): focuses on bandwidth-intensive
services, such as High Definition (HD) video and Augmented Reality (AR).

Ultra-Reliable Low-Latency Communication (URLLC): focuses on services
that are extremely sensitive to latency and reliability, such as autonomous
vehicle and industrial automation services.

Massive Machine-Type Communications (mMTC): covers scenarios with high
connection density, such as smart city.
These scenarios have different kinds of network feature and performance
requirements, which cannot be met using a single network.
5
Background of Network Slicing
Cloud Services
With the rapid development of the cloud and Internet, more and more
enterprises are adopting digital transformation, as shown in Figure 2-2.
Figure 2-2 Digital transformation of various industries (cloud migration)
According to research by the International Data Corporation (IDC), 100% of
enterprises will use cloud services by 2025, and 85% of enterprise applications
will be deployed on clouds. Through digital transformation, enterprises hope to
achieve asset-light operations by gradually migrating their internal IT support
systems and production systems to clouds. This will bring greater efficiency and
agility to enterprises using cloud services. Cloudification of enterprise
applications transforms the deployment of Information and Communications
6
Background of Network Slicing
Technology (ICT) for enterprises, reconstructs private line networks between
enterprise sites and clouds, between enterprise sites, and between clouds, and
reshapes carriers' Business to Business (B2B) services. One-stop cloud-network
services are the most critical requirements of enterprise ICT departments.
In the huge enterprise ICT market, more and more industry players are creating
different solutions to meet user requirements. Public cloud providers tap into the
cloud backbone network field to provide one-stop cloud-network services,
gradually eliminating the need for site-to-Internet and site-to-site private lines.
In addition, vendors involved with Software-Defined Networking in a Wide Area
Network (SD-WAN) provide flexible and cost-effective solutions to meet
customers' interconnection requirements. These products and services not only
transform private line connections, but also provide flexible connection, fast
provisioning, and dynamic adjustment capabilities. Consequently, the market
share of carriers' traditional private line services is under threat. To maintain
competitiveness in the B2B market, carriers must leverage their advantages in
networks and provide flexible, agile, and SLA-guaranteed private line services
with wide coverage and cloud-network convergence capabilities.
2.2 Challenges Facing IP Networks
With the emergence of diversified services in the 5G and cloud era, meeting
diversified, differentiated, and complex requirements of various services on an IP
network is a new challenge.
Ultra-Low Latency
IP networks typically consist of access, aggregation, and backbone layers.
Because users are unlikely to all use the maximum bandwidth at the same time,
the planned bandwidth is converged from the access layer to the aggregation
layer (typically at a ratio of 4:1, although this varies depending on carriers) and
then to the backbone layer. Through such convergence, the statistical
multiplexing capability of IP networks can be fully utilized, allowing resources to
be shared and greatly reducing the network construction cost. The downside of
this convergence is that a network may encounter high-speed and multiinterface access but low-speed and single-interface output, resulting in
congestion. Although routers use large interface buffers to solve the packet loss
7
Background of Network Slicing
problem caused by congestion, buffering packets leads to higher queuing latency
if congestion occurs.
With the emergence of diversified 5G services, such as those shown in Figure 2-3,
different services have different requirements on bandwidth and latency. For
example, live video services require high bandwidth, and burst traffic is likely to
cause instantaneous congestion; and services such as telemedicine, gaming, and
precision manufacturing require ultra-low latency. Requirements on strict latency
can be met if channels with differentiated latency are provided based on
services.
Figure 2-3 Diversified new 5G services
Security Isolation
Some enterprises in vertical industries, such as government, finance, and
healthcare, have specific requirements (shown in Figure 2-4) on security and
stability of their core services, such as production, manufacturing, and interactive
services. To ensure that these core services are not affected by other services (for
example, information management and public network services), enterprises
usually isolate them by using private networks. However, factors such as
construction costs, Operations and Maintenance (O&M), and rapid service
expansion have given rise to enterprises seeking new ways to carry their core
services while meeting security isolation requirements. With statistical
multiplexing in traditional IP networks, services may preempt each other's
8
Background of Network Slicing
resources. As such, only best-effort services can be provided, and the security
isolation capability cannot be provided. In addition, traditional Multi-Service
Transfer Platform (MSTP) private lines are becoming obsolete, but some services
they carry, such as financial and government private line services, require
security isolation and exclusive resources.
Figure 2-4 Key network indicators required by some industry enterprises
Extremely High Reliability
High-value services require IP networks to provide high availability, which is one
of the key network indicators shown in Figure 2-4. Premium enterprise private
line services, such as those in government, finance, and healthcare sectors,
usually require an availability of up to 99.99%. This increases to 99.999% for 5G
services (especially URLLC services). And for mission-critical services related to
social and human safety, such as remote control and high-voltage power supply,
an extremely high availability of 99.9999% is essential. As such, it is crucial to
provide highly reliable private lines on an IP network to carry these services.
9
Background of Network Slicing
Flexible Connections
With the continuous development of services in the 5G and cloud era, the
singular service type evolves toward diverse types, and the singular traffic
pattern evolves toward multi-direction patterns. This results in more flexible,
complex, and dynamic network connections, as shown in Figure 2-5. As 5G core
Network Elements (NEs) are cloudified, User Plane Functions (UPFs) are moved
closer to users, and Mobile Edge Computing (MEC) is widely applied, the
connections between base stations, between base stations and different network
layers of Data Centers (DCs), and between different network layers of DCs
become increasingly complex and change dynamically. This requires networks to
provide any connection on demand. In addition, because different industries,
services, and users have different service scopes and access locations in the
network and cloud, customized network topologies and connections are required.
Figure 2-5 Complex IP network connections caused by diversified services
Refined and Intelligent Service Management
With the emergence of diversified services in the 5G and cloud era, various
services not only pose differentiated service requirements on networks, but also
pose requirements on network services in terms of being dynamic, real-time, and
more. On traditional IP networks, service planning is relatively static and the
statistics collection and monitoring of network utilization is performed at a
granularity of minutes, ignoring traffic burst characteristics at the micro level.
10
Background of Network Slicing
This cannot prevent services from affecting each other, guarantee SLAs, or meet
requirements of services on dynamic deployment and flexible adjustment.
Tenant-level refined and intelligent management are required for services;
however, one traditional IP network cannot meet such requirements.
2.3 Background of Network Slicing
A traditional shared IP network cannot efficiently provide guaranteed SLAs for all
services, let alone network isolation and independent operation. To meet the
differentiated requirements of various services on the same network, network
slicing is introduced. With network slicing, carriers can build multiple dedicated,
virtualized, and isolated logical networks on a general physical network to meet
the differentiated requirements of different customers for network connections,
resources, and other functions. Figure 2-6 shows an example of network slicing.
11
Background of Network Slicing
Figure 2-6 Example of network slicing
Network slicing is a new service mode introduced to carrier networks in the 5G
and cloud era. With network slicing, a carrier can provide different network slice
services for multiple tenants over a shared network infrastructure to meet
differentiated network requirements of different industries. And vertical industry
customers can use the network as slice tenants.
12
Background of Network Slicing
Chapter 3
Benefits of Network Slicing
Abstract
Based on network slicing, carriers can provide resource isolation,
differentiated SLAs, high reliability, flexible topology customization, and
automatic slice management to build intelligent cloud networks, helping
enterprises achieve digital transformation.
3.1 Resource and Security Isolation
Traffic of different industries, services, and users is carried on the same network
through different network slices, which need to provide different types and
degrees of isolation based on services and customer requirements.
In terms of service quality, the purpose of network slice isolation is to prevent a
service burst or abnormal traffic in a slice from affecting other slices in the same
network, thereby ensuring that services in different network slices do not affect
each other. This is especially important for vertical industries, such as smart grid,
smart healthcare, and smart port, which have strict requirements on latency and
jitter and whose performance is highly sensitive to impacts from other services.
In terms of security, information about private line services (such as financial and
13
Benefits of Network Slicing
government services) or users in a network slice should not be accessible to
users in other network slices. In this case, effective security isolation measures
need to be taken between different slices.
Based on the degree of isolation, network slices on IP networks provide three
levels of isolation: service, resource, and O&M isolation.

Service isolation: Different network slices are established for different
services in the public network to isolate service connections and access. Note
that service isolation cannot guarantee SLAs; rather, it provides isolation for
some traditional services that do not have strict SLAs. This means that one
network slice may still be affected by another, even if service isolation is
used.

Resource isolation: Network resources are defined for exclusive use on a perslice basis, or for sharing among multiple slices. Resource isolation is
paramount for 5G URLLC services, which usually have strict SLAs and do not
tolerate interference from other services. Based on the degree of isolation,
resource isolation includes hard isolation and soft isolation.
−
Hard isolation ensures that slices are provided with exclusive network
resources, preventing any interference between services in different
slices. For example, FlexE interfaces or channelized sub-interfaces can
be used to provide hard isolation for network slices.
−
Soft isolation allows each slice to use not only a set of dedicated
resources, but also some resources shared with other network slices.
This allows services to be isolated to some extent without sacrificing
certain statistical multiplexing capabilities. For example, Quality of
Service (QoS)/Hierarchical Quality of Service (HQoS) can be used to
provide soft isolation for network slices.
Based on both hard and soft isolation, carriers can select the optimal
combination of resource isolation mechanisms between network slices to
meet their resource requirements. This allows a single physical network to
meet differentiated SLAs.

O&M isolation: In addition to service isolation and resource isolation, some
tenants require independent O&M of network slices allocated by carriers,
similar to using private networks. Network slicing provides O&M isolation
through open interfaces on the management plane.
14
Benefits of Network Slicing
Take a smart grid scenario as an example. As shown in Figure 3-1, smart grid
services are classified as control or collection services. The two types of services
have different SLA requirements, and service isolation needs to be provided.
Network slicing provides resource and security isolation between smart grid and
public network services, as well as isolation between smart grid control and
collection services.
Figure 3-1 Isolation between different power grid services
3.2 Differentiated SLA Assurance
In addition to bringing a sharp increase in network traffic, the rapid development
of network services also gives rise to extreme requirements on network
performance. Because different industries, services, and users have different SLA
requirements on network bandwidth, latency, and jitter, the same network
infrastructure needs to meet differentiated SLA requirements in different service
scenarios. On a shared network infrastructure, network slicing provides
differentiated SLA assurance for different industries, services, and users.
Network slicing enables carriers to gradually transform from selling the same
services to selling differentiated services for Business to Home (B2H), Business to
15
Benefits of Network Slicing
Business (B2B), and Business to Consumer (B2C). As shown in Figure 3-2, a
carrier provides differentiated services for tenants in the form of slice offerings.
To drive new value growth in the future, carriers will predominantly provide ondemand, customized, and differentiated services.
Figure 3-2 Slice as a service, providing differentiated network services for tenants
3.3 Extremely High Reliability
Assurance
On IP networks, high-value and URLLC services require high availability and
millisecond-level failure recovery. SRv6-based network slicing provides local
protection technologies, such as Topology-Independent Loop-Free Alternate (TILFA) and midpoint protection, for any failure point on an IP network. These
technologies can significantly increase the protection success rate and enhance
the reliability of IP network slices. In addition, link failure-triggered switching in
each network slice can be controlled within the slice without affecting other
slices, as shown in Figure 3-3.
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Benefits of Network Slicing
Figure 3-3 Link failure-triggered switching in a network slice
3.4 Flexible Topology Connection
Customization
The continuous development of services in the 5G and cloud era gives rise to
network connections that are more flexible, complex, and dynamic. As shown in
Figure 3-4, network slicing uses Flexible Algorithms (Flex-Algos) to provide ondemand customization of logical network topology connections, meeting
differentiated network connection requirements of different industries, services,
and users.
17
Benefits of Network Slicing
Figure 3-4 Flex-Algo-based flexible customization of topology connections
After a logical topology and connection are customized for users in a network
slice, the users are aware of only the network slice's logical topology and
connection — not the basic network's full network topology. In addition,
services deployed in a network slice are limited to the topology corresponding to
that network slice. For network slice users, this simplifies the network
information that they need to perceive and maintain. And for carriers, this
prevents excessive internal information about basic networks from being
exposed to network slice users, improving network security.
18
Benefits of Network Slicing
3.5 Automated Slice Management
As service types and scales continuously increase, the complexity involved in
network management grows rapidly. This means that managing networks
manually is no longer a feasible option for carriers. Instead, they need to
manage these networks dynamically and efficiently, which requires automated
network management technologies. The network slice manager provides fulllifecycle management and tenant-level refined service management for network
slices, streamlining the entire process from user intent to service provisioning, as
shown in Figure 3-5.

Refined slice planning: Slices based on service requirements provide
differentiated SLAs, fully meeting the bearer requirements of various
customers and preventing wastage of slice resources.

Slice automation: Minute-level slice automation based on an intelligent
network controller implements fast deployment and on-demand capacity
expansion of slices.

SLA visualization: An intelligent network controller visualizes the network
topology and resources of service-level slices and supports SLA visualization
based on In-situ Flow Information Telemetry (IFIT) measurement.
19
Benefits of Network Slicing
Figure 3-5 Full-lifecycle management of network slices
With the ongoing development of network management automation,
intelligence technologies will be widely used in each phase of network slice
management to implement intelligent network management.
20
Benefits of Network Slicing
Chapter 4
Architecture of Network
Slicing
As shown in Figure 4-1, the IP network slicing architecture consists of three
layers: network slice management layer, network slice instance layer, and
network infrastructure layer.
21
Architecture of Network Slicing
Figure 4-1 IP network slicing architecture
Network Slice Management Layer
This layer provides lifecycle management for network slices. To meet the
requirements of different services, network slicing divides a physical network into
multiple logical network slices. Because this increases the management
complexity of network slices, automated and intelligent management of network
slices is crucial, involving the planning, deployment, O&M, and optimization of
network slices, as shown in Figure 4-2.
22
Architecture of Network Slicing
Figure 4-2 Network slice lifecycle management

Slice planning: Physical links, forwarding resources, service Virtual Private
Networks (VPNs), and tunnels need to be planned for network slices in
order to guide network slice configurations and parameter settings. In
addition, multiple solutions for network slice planning are provided, such as
network-wide slicing based on fixed bandwidth, flexible customization of
topology connections, and automatic calculation of slice topologies and
required resources based on service models and SLA requirements.

Slice deployment: Network slice instances need to be deployed, including
creating network slice interfaces and configuring bandwidth, VPNs, and
tunnels for network slices.

Slice O&M: Functions such as network slice visualization and fault O&M
need to be provided. IFIT is used to monitor service latency and packet loss,
and telemetry is used to report a network slice's traffic volume, link status,
and service quality information in order to show the network slice status in
real time.
23
Architecture of Network Slicing

Slice optimization: Network slice performance needs to be balanced with
network costs to meet SLA requirements through various operations, such as
slice forwarding resource prediction and intra-slice traffic optimization.
Network Slice Instance Layer
This layer enables the instantiation of different logical network slices on a
physical network, supports on-demand customized logical topology connections,
and associates the logical topologies of network slices with the set of network
resources allocated to the slices. In this way, network slices are formed to meet
specific service requirements.
The network slice instance layer covers VPNs at the overlay layer and Virtual
Transport Networks (VTNs) at the underlay layer. VPNs provide logical
connections for services within a network slice and can isolate services of
different network slices. VTNs, on the other hand, provide logical network
topologies for slice service connections, and provide exclusive or partially shared
network resources to meet SLAs of network slice services. In this regard, a
network slice instance is the integration of a VPN service as the overlay with an
appropriate VTN as the underlay. Because there are various overlay VPN
technologies that are mature and widely used, the following sections mainly
describe the VTN's functions. Network slice mentioned later typically refers to a
VTN that carries network slice services.
VTN functions can be broken down into data plane functions and control plane
functions.

Data plane: adds network slice identifiers to data packets so that packets of
different network slices can be forwarded according to the forwarding
entries of the corresponding network slices. Note that these identifiers are
generic and agnostic to various resource partitioning technologies used at
the network infrastructure layer. Currently, network slice IDs can be carried
using SRv6 Segment Identifiers (SIDs) or dedicated slice IDs in data packets.

Control plane: distributes and collects each network slice's attributes (such
as the topology and resource) and their status information. In addition, the
control plane calculates and provisions routes and paths based on the
network slice's topology and resource constraints, mapping service flows of
different network slices to corresponding network slice instances on demand.
Currently, the network slice topology can be flexibly customized using Flex-
24
Architecture of Network Slicing
Algos on the control plane, and path information within network slices can
be delivered using SRv6 Policies.
Network Infrastructure Layer
This layer is a physical network used to create IP network slice instances. To
meet services' requirements on resource isolation and SLA assurance, the
network infrastructure layer needs to have flexible and fine-grained resource
reservation capabilities so that it can partition the physical network's forwarding
resources into multiple sets of isolated resources based on a required granularity
for allocation to different network slices. Some candidate resource partitioning
technologies include Flexible Ethernet (FlexE) sub-interface, channelized subinterface, and Flex-channel.
25
Architecture of Network Slicing
Chapter 5
Network Slicing Solutions
Abstract
This chapter mainly describes the design principles and characteristics of
the affinity-based and slice ID-based network slicing solutions, and
compares the two solutions. This will help you understand how network
slicing implements functions such as resource isolation and
differentiated SLA assurance.
5.1 Overview of Network Slicing
Solutions
Two common network slicing solutions are currently available: affinity-based
network slicing solution and slice ID-based network slicing solution. This section
briefly describes the two solutions. For further details, see 5.2 and 5.3 .

Affinity-based network slicing solution
As shown in Figure 5-1, the affinity-based network slicing solution uses an
affinity to identify a slice. Each affinity corresponds to one network slice.
26
Network Slicing Solutions
Affinities can identify the forwarding resource interfaces of different slices,
and each resource interface requires an IP address and SR SID. In the control
plane, each slice calculates Segment Routing-Multiprotocol Label Switching
(SR-MPLS) and SRv6 Policy paths based on the affinity for service bearing. In
the data plane, slice-specific service packets are encapsulated with the SRMPLS label stack or SRv6 Segment Routing Header (SRH) and forwarded
hop by hop. This book uses SRv6 as an example to describe the affinitybased network slicing solution.
Figure 5-1 Affinity-based network slicing solution

Slice ID-based network slicing solution
As shown in Figure 5-2, the slice ID-based network slicing solution
introduces a globally unique slice ID to identify a network slice. Each slice ID
corresponds to one network slice and identifies the forwarding resource
interfaces in the slice — there is no need to configure an independent IP
address and SR SID for each slice interface. In the control plane, SR-MPLS,
SRv6 Best Effort (BE), or Traffic Engineering (TE) Policy paths are calculated
based on slice IDs for service bearing. In the data plane, each forwarding
node matches the slice resource interface based on the slice ID carried in a
27
Network Slicing Solutions
data packet for service forwarding. This book uses SRv6 as an example to
describe the slice ID-based network slicing solution.
Figure 5-2 Slice ID-based network slicing solution
5.2 Affinity-based Network Slicing
Solution
Affinity-based network slicing uses the existing control plane and data plane
protocol mechanisms to quickly establish and adjust network slices based on
service requirements. It is applicable for fast deployment of network slices in
legacy networks.
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Network Slicing Solutions
What Is an Affinity?
An affinity, also called admin group or color, is a control information attribute of
a link. As shown in Figure 5-3, affinities are used to identify links by assigning
the links different colors (such as blue and yellow). Links identified with the
same color form a logical network topology.
Figure 5-3 Using affinities to identify links
Affinity-based Network Slicing
As shown in Figure 5-4, an affinity is used as a control plane identifier of a
network slice, and different affinities are configured on resource reserved
interfaces or sub-interfaces corresponding to each network slice. In this way, an
independent network slice is planned based on the affinity.
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Network Slicing Solutions
Figure 5-4 Affinity-based network slicing
Affinity information (along with other link information) is flooded in the network
through the Interior Gateway Protocol (IGP)/Border Gateway Protocol-Link State
(BGP-LS) and is reported to the network slice controller. After collecting the link
status information of the entire network, the network slice controller may form
an independent network slice view based on each affinity, and compute a
constrained forwarding path for slice services on a per-slice basis.
As shown in Figure 5-5, in the data plane, different SRv6 End.X SIDs need to be
allocated to resource interfaces or sub-interfaces reserved for different network
slices. In this way, each forwarding node on the network can determine the
interface or sub-interface resources for packet forwarding based on the SRv6
SIDs.
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Network Slicing Solutions
Figure 5-5 SRv6-based data plane
The network slice controller computes an explicit path based on slice constraints.
The path can then be orchestrated into a SID list composed of SRv6 SIDs relating
to interfaces or sub-interfaces. This SID list can explicitly indicate the forwarding
path of packets and a group of reserved forwarding resources on the path in the
SRv6 network. The controller uses a BGP SR Policy to deliver the SRv6 explicit
path of each slice to the ingress and steer the services — such as Layer 2 Virtual
Private Network (L2VPN) and Layer 3 Virtual Private Network (L3VPN) services
— planned in the slice to the SRv6 Policy path of the corresponding slice. As
shown in Figure 5-6, if the destination address of a service matches the endpoint
of an SRv6 Policy and the service preference (identified by the color extended
community attribute of the corresponding VPN route) is the same as that of the
SRv6 Policy, the service can be steered to the SRv6 Policy for forwarding. To
ensure resource isolation between different slices and provide differentiated
paths for different services within a slice, an SRv6 Policy restricts the forwarding
of service packets using the paths and reserved resources within a slice. This
makes it possible to meet the SLA requirements of different slice users and
different services within a slice.
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Network Slicing Solutions
Figure 5-6 Steering services to a specified SRv6 Policy path based on an affinity
5.3 Slice ID-based Network Slicing
Solution
Slice ID-based network slicing introduces dedicated global slice IDs to data
packets in order to identify network slices with a simpler and more
straightforward approach. This differs from affinity-based network slicing, which
uses SRv6 SIDs to identify network slices. In affinity-based network slicing, each
device that reserves resources for network slices must allocate a different SRv6
locator and a set of SIDs to each network slice. Consequently, the number of
SRv6 locators and SIDs to be allocated increases rapidly as the number of
network slices increases, bringing challenges to network planning and
management. This also multiplies the amount of information to be advertised by
the control plane and the number of forwarding entries in the data plane,
bringing scalability problems to the network. By using dedicated global slice IDs,
slice ID-based network slicing prevents the number of SRv6 locators and SIDs
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Network Slicing Solutions
from multiplying with the number of slices, effectively relieving the scalability
pressure caused by the increase of network slices in the control and data planes.
What Is a Slice ID?
The biggest change brought by network slicing is the shift from a traditional
network consisting of one physical plane to a three-dimensional network
consisting of many logical planes. As shown in Figure 5-7, each network node in
a logical plane is identified using a unique IP address, which is essential for
packet forwarding. In a multi-plane three-dimensional network, however, this
one-dimensional identification method causes major issues. Because different
slices have different network topologies or network resources, this method
requires a different IP address to be allocated to each node in each slice for
identification. For example, if there are 1000 network nodes and 200 network
slices need to be created, 200,000 IP addresses need to be planned. This brings
major challenges to network deployment and performance.
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Network Slicing Solutions
Figure 5-7 Network slice address identification model (one-dimensional identification)
To resolve this problem, two-dimensional addressing is introduced in order to
identify network slices of different logical planes. As shown in Figure 5-8, in the
two-dimensional identification method, the IP address of a physical network
node and a network slice ID are used together to uniquely identify a logical node
in the network slice. In this way, only one set of IP address identifiers is required,
and address planning and configuration do not need to be separately performed
for each network slice — regardless of the number of network slices planned for
a network. In addition, using a two-dimensional address identifier can
significantly reduce the number of routes in a network slice, easily supporting Klevel network slices.
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Network Slicing Solutions
Figure 5-8 Network slice address identification model (two-dimensional identification)
To support a two-dimensional address identifier, a global network slice ID needs
to be added to data packets. Typically, the Hop-by-Hop (HBH) Options header of
an IPv6 packet carries the global data plane identifier (network slice ID) of a
network slice. As shown in Figure 5-9, the slice ID specifies the slice over which
the packet is carried.
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Network Slicing Solutions
Figure 5-9 Format of an IPv6 packet encapsulated with an HBH Options header
Slice ID-based Network Slicing
Traditional IPv6 forwarding is based on destination addresses. Slice ID-based
network slicing reuses the addresses of the basic network, without requiring an
additional IPv6 address to be separately allocated to each slice. Slice IDs that are
globally planned and allocated are used to identify the forwarding resources
allocated by network devices to network slices. In this case, the default and
service network slices differ only in forwarding resources and data plane
identifiers. In the data plane, network devices use the destination address and a
slice ID to instruct packet forwarding in a network slice. The destination address
is used to address a packet forwarding path, whereas the slice ID is used to
select forwarding resources corresponding to a packet. In the control plane,
different network slices can reuse protocol sessions and route calculation,
reducing the pressure caused by an increase in the slice scale on the control
plane. As shown in Figure 5-10, nine network slice instances are created: three
each on DeviceA, DeviceB, and DeviceC. An independent slice ID is used to
identify the resource interface or sub-interface allocated to each network slice on
a physical port. On a network node, all network slices share the same IPv6
address and control-plane protocol session.
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Network Slicing Solutions
Figure 5-10 Slice ID-based data plane
For a slice ID-based network slice, a network device needs to generate two
forwarding tables. One is a routing table, which is used to determine the Layer 3
outbound interface based on the destination address of a packet. The other is a
slice interface's slice ID mapping table, which is used to determine a slice's
reserved resources on the Layer 3 interface based on the slice ID in a packet. As
shown in Figure 5-11, after a service packet reaches a network device, the
network device searches the routing table based on the destination address in
order to obtain the next-hop device and Layer 3 outbound interface. The device
then searches the slice interface's slice ID mapping table based on the slice ID to
determine reserved resources (sub-interfaces or channels) on the Layer 3
outbound interface. Finally, the device uses the corresponding sub-interface or
channel to forward the service packet.
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Network Slicing Solutions
Figure 5-11 Steering services into a specified SRv6 Policy path based on a slice ID
The slice ID-based network slicing solution has the following advantages:

Multiple network slices reuse the same address identifier, simplifying
network slice deployment.

Multiple network slices share the routing table. Slice IDs are used for the
resource mapping table lookup to provide differentiated forwarding of
network slices, reduce the scale of routes in slices, and improve convergence
performance.

Topology and resource decoupling is achieved to reuse the slice topology as
much as possible, reduce the overhead caused by the protocol used by the
controller to maintain multiple slice topologies, and increase the slice scale.
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Network Slicing Solutions
5.4 Comparison Between Network
Slicing Solutions
Table 5-1 compares the affinity-based network slicing solution with the slice IDbased network slicing solution.
Table 5-1 Comparison between network slicing solutions
Item
Affinity-based
Slicing Solution
Network
Slice specifications
16 (maximum)
Thousand-level
Forwarding plane isolation
FlexE/Channelized sub-interface
FlexE/Channelized
technology
Slice ID-based Network
Slicing Solution
sub-
interface/Flex-channel
SLA assurance effect
Strict assurance
Strict assurance
Configuration complexity
Complex
Simple
Whether IP addresses and
Yes
No
Pre-deployment
Pre-deployment
Layer 3 protocols need to
be configured for service
slice interfaces
Service
slice
deployment
mode
+
on-
demand deployment (ondemand slicing)
SRv6 working mode
Whether
a
controller
is
SRv6 Policy
SRv6 BE/SRv6 Policy
Yes
Yes
A small number of slices are
Strict
required, and fast deployment
required for thousand-level
can be implemented in legacy
users, and massive network
networks.
slices are required.
required
Application scenario
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Network Slicing Solutions
SLA
assurance
is
Item
Affinity-based
Slicing Solution
Evolution path
The
affinity-based
Network
network
Slice ID-based Network
Slicing Solution
N/A
slicing solution can evolve to
the
slice
ID-based
network
slicing solution.
Currently, although the affinity-based network slicing solution can be quickly
deployed on live networks, its limitations include supporting only a small number
of slices and involving complex configurations. The slice ID-based network slicing
solution does not have such limitations and is therefore the preferred choice for
large-scale network slice deployment.
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Network Slicing Solutions
Chapter 6
Suggestions on Network
Slicing Deployment
Abstract
The deployment of network slicing usually requires the help of a
network controller. Before deploying network slicing, you need to
consider factors such as networking scenarios and SLA requirements.
This chapter provides suggestions on deploying network slicing based on
networking scenarios and reserving resources based on SLA
requirements.
6.1 Deploying Network Slicing Based
on Networking Scenarios
Different network slicing solutions have different deployment modes in different
networking scenarios. Before deploying network slicing, you need to determine
which solutions best meet your networking requirements.
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Network Slicing in Different Networking Scenarios
According to the network connection model, there are three typical networking
scenarios: Multipoint-to-Multipoint (MP2MP), Point-to-Point (P2P) private line,
and hybrid network modes. As shown in Figure 6-1, network slices deployed in
the three networking scenarios are called MP2MP network slices, P2P private line
network slices, and hybrid network slices.
For MP2MP network slices, the entire physical network or a portion of it can be
sliced, and nodes in a MP2MP network slice are fully meshed. Typical MP2MP
network slices include carrier self-operating service slices, industry-specific slices,
and VIP customer-specific slices. Typically, network resources cannot be shared
between different MP2MP network slices, but can be shared between different
connections in the same slice. An MP2MP network slice usually requires
multipoint-to-multipoint interconnection, resulting in many connections and
complex connection relationships. For example, in an MP2MP network slice with
1000 nodes, to implement interconnection between any two nodes, about
1,000,000 point-to-point explicit paths need to be established. The complexity
brought by such a large number of paths puts great pressure on network
performance. As such, it is recommended that Flex-Algos be used to customize
slice topologies and provide distributed path computation for different MP2MP
network slices. A Flex-Algo is a customized algorithm for constrained path
computation. With Flex-Algos, you can define algorithm values and a series of
parameters (including metric types, algorithm types, and link constraints) to
flexibly customize topologies and path computation rules. In this way, network
nodes can perform distributed path computation based on constraints, reducing
the cost of computing and maintaining a large number of tunnels.
For P2P private line network slices, such as government and enterprise as well as
enterprise site-to-site private line network slices, slicing is implemented based on
specified service access points, and such private line network slices usually
require exclusive bandwidth resources. A private line network slice usually
requires interconnection only between limited service access points, and the
connection relationship between access points is relatively fixed. As such, while a
single private line network slice has only a limited number of connections, the
number of private line network slices on an entire network is relatively large. If
each P2P private line network slice is deployed using a Flex-Algo, a network
needs to support a large number of Flex-Algos, placing great pressure on
network performance. For this reason, it is recommended that SRv6 Policies be
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Suggestions on Network Slicing Deployment
used to provide explicit paths for connections in P2P private line network slices
to implement differentiated forwarding.
A hybrid network slice is a combination of an MP2MP network slice and a P2P
private line network slice, and as such has both of their characteristics.
Specifically, a hybrid network slice combines a Flex-Algo and SRv6 Policy: a FlexAlgo is used to customize the slice topology and provide distributed
differentiated path computation, whereas an SRv6 Policy is used to provide
deterministic forwarding paths for some service flows in a slice.
Figure 6-1 Networking modes of network slices
While both the affinity- and slice ID-based network slicing solutions can meet
the requirements of the three networking scenarios, their implementation
processes differ. The following provides suggestions for deploying the two
solutions in the MP2MP network slice and P2P private line network slice
scenarios. A hybrid network slice is a combination of an MP2MP network slice
and a P2P private line network slice, and details are not described herein.
Application of the Affinity-based Network Slicing
Solution in Networking Scenarios
The affinity-based network slicing solution uses an SRv6 Policy to explicitly
specify a service path with guaranteed resources between two endpoints on a
network. This solution can meet the deployment requirements of P2P private line
network slices and can also be used for MP2MP network slices. An SRv6 Policy is
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Suggestions on Network Slicing Deployment
used between any two network nodes to specify a service path with guaranteed
network resources, and then a set of SRv6 Policies between each pair of multiple
network nodes forms an MP2MP network slice with guaranteed network
resources.
When there are a large number of service connections in an MP2MP network
slice and the connection relationships dynamically change, a large number of
SRv6 Policy paths need to be calculated and delivered for the affinity-based SRv6
Policy network slice. This may put much pressure on the performance of the
controller and network devices. As such, this type of MP2MP network slice can
use the affinity- and Flex-Algo-based slicing solution, as shown in Figure 6-2. In
this solution, Flex-Algos are used to define different network slices' topologies
and path computation constraints, which are flooded to each network device
through an IGP. Network devices can then compute SRv6 BE forwarding paths
that meet slice constraints based on the topologies, and use the reserved
network resources that are identified by affinities of the network slice for service
packet forwarding. In this case, most service packets in a network slice are
forwarded using Flex-Algo-based SRv6 BE paths with guaranteed resources. SRv6
Policies are mainly used to provide explicit paths for some services in the slice,
reducing the number of SRv6 Policies required by the slice, so that MP2MP
network slice services can be delivered more efficiently.
Figure 6-2 Affinity- and Flex-Algo-based MP2MP network slice solution
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Suggestions on Network Slicing Deployment
Application of the Slice ID-based Network Slicing
Solution in Networking Scenarios
In the slice ID-based network slicing solution, slice IDs are globally planned and
allocated to identify the subset of forwarding resources that network devices
allocate to network slices. This can meet the requirements of both MP2MP
network slices and P2P private line network slices, but the implementation
solutions differ between them. An MP2MP network slice consists of a large
number of connections and a complex network topology. To cope with this
situation, slice IDs and Flex-Algos can be combined to provide topology
customization and resource guarantee for network slices, as shown in Figure 6-3.
After Flex-Algos are enabled on network nodes, the network nodes perform path
computation according to the algorithm parameters defined by the Flex-Algos.
Then, based on the link constraints defined in Flex-Algos, a physical network can
be divided into different logical topologies to meet differentiated topology
customization requirements of network slices. In addition, Flex-Algos allow
different metric types to be used to compute differentiated paths for network
slices with the same topology, meeting differentiated SLA requirements of
network slices. After Flex-Algos determine slice topologies and packet forwarding
paths, slice IDs are used to identify the network resources reserved for the slices
and used during packet forwarding.
Figure 6-3 MP2MP network slices based on slice IDs+Flex-Algos
As shown in Figure 6-4, an SRv6 Policy is used to specify a service path with
guaranteed resources between two endpoints on the network. End SIDs and
End.X SIDs are allocated to the network nodes and Layer 3 interfaces,
respectively, while a slice ID identifies a private line tunnel with guaranteed
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Suggestions on Network Slicing Deployment
resources on the network. Multiple SRv6 Policies can use the same End/End.X SID
to specify explicit paths, and different slice IDs to identify different resources
reserved for the slices on the paths. This ensures that differentiated SLA
requirements of different P2P private line network slices can be met.
Figure 6-4 Slice ID-based P2P private line network slices
6.2 Resource Reservation Based on
Service Requirements
Resource reservation technology is key to providing differentiated SLA assurance
for network slicing solutions. It partitions forwarding resources in a physical
network into multiple mutually isolated resource groups for different network
slices to use. This ensures that resources are available to meet service
requirements in network slices, and prevents or controls resource contention and
preemption between different network slices. This section describes common
resource reservation technologies (including FlexE interface, channelized subinterface, and Flex-channel) in network slicing solutions. In actual network
deployment, proper resource reservation technologies can be selected based on
different service requirements for refined allocation of network resources.
FlexE Interface
FlexE technology uses FlexE shim to pool physical interface resources based on
slots. A high-bandwidth physical interface is flexibly divided into several sub-
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Suggestions on Network Slicing Deployment
channel interfaces (FlexE interfaces) based on a slot resource pool, implementing
flexible and refined management of interface resources. A FlexE interface is
equivalent to a physical interface, and its bandwidth resources are strictly
isolated from those of other FlexE interfaces. FlexE interfaces have extremely
little latency interference with each other and can provide ultra-low latency. This
makes FlexE interfaces suitable for carrying URLLC services that have strict
requirements on latency SLA, such as differential protection services of power
grids.
FlexE interface-based slice resource reservation has the following characteristics:

Guaranteed performance: The latency is stable and no packet loss occurs
after slicing; hard isolation is implemented between slices; bandwidth is
guaranteed; and services in different slices do not affect each other.

Fine-grained slicing: Huawei supports a minimum slicing granularity of 1
Gbit/s with FlexE. In contrast, only 5 Gbit/s slicing granularity is supported in
the industry.

Scalable slicing: When used with other resource reservation technologies,
such as channelized sub-interface or Flex-channel, FlexE supports
hierarchical slicing to meet requirements for more complex service isolation.

Instant slicing: Slices can be deployed in minutes for fast service deployment.
Slice resources can be pre-deployed through an intelligent network
controller or deployed on demand for services.

Reliable slicing: The slice bandwidth is dynamically adjusted, and services are
stable. Intelligent O&M capabilities such as slice-based SLA visualization are
supported.
Channelized Sub-interface
Channelized sub-interfaces are based on the sub-interface model. Leveraging the
HQoS mechanism, bandwidth can be flexibly allocated by configuring
independent channelized sub-interfaces for network slices. Each network slice is
allocated exclusive bandwidth and a dedicated scheduling tree to reserve
resources for slice services. A channelized sub-interface is equivalent to an
independent "lane" in a road. Each of these lanes is assigned to each network
slice on a network device. The lane between different network slices is fixed, and
cannot be changed during service traffic transmission. This ensures strict
isolation of services in different slices, and effectively prevents resource
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Suggestions on Network Slicing Deployment
preemption between services when traffic bursts occur. In addition, flexible lanes
can be assigned within the fixed lane of each network slice, allowing
differentiated scheduling to be performed in the same slice based on the priority
of packets.
Channelized sub-interfaces are independent logical interfaces that reside on a
physical interface. They are suitable for creating logical networks and are usually
used to provide MP2MP network slice services with guaranteed bandwidth.
Channelized sub-interface-based slice resource reservation has the following
characteristics:

Strict resource isolation: Based on the sub-interface model, resources are
reserved in advance to prevent slice services from preempting resources
when traffic bursts occur.

Fine bandwidth granularity: Channelized sub-interfaces can be used together
with FlexE interfaces, dividing a high-rate interface into sub-interfaces with
low bandwidth. The sub-interfaces can be used to provide industrial network
slices.
Flex-channel
A Flex-channel provides a flexible and fine-granularity interface resource
reservation mode. In contrast to a channelized sub-interface, a Flex-channel does
not have a sub-interface model and is easier to configure. As such, a Flexchannel is more suitable for scenarios where network slices are quickly created
on demand.
Flex-channel-based slice resource reservation has the following characteristics:

On-demand slicing: Service-based slicing requirements are quickly delivered
by a controller to implement on-demand slicing.

Massive network slices: A Flex-channel supports a minimum bandwidth
granularity of 1 Mbit/s, meeting the slice bandwidth requirements of
enterprise users.
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Suggestions on Network Slicing Deployment
Comparison Between Different Resource
Reservation Technologies
Table 6-1 compares different resource reservation technologies.
Table 6-1 Comparison between resource reservation technologies
Item
FlexE Interface
Channelized
interface
Isolation
Exclusive use of Traffic
TM
Manager (TM) resources;
reservation;
port resource isolation
resource sharing
Latency
A
A
assurance
increase of up to 10 µs
single-hop
latency
Sub-
resource
single-hop
port
Flex-channel
TM
port
resource sharing
latency
A single-hop latency
increase of up to 100
increase of up to 100
µs
µs
Granularity
1 Gbit/s
2 Mbit/s
1 Mbit/s
Application
Industrial network slice
Industrial network slice
Enterprise
and enterprise MP2MP
network
network
enterprise
scenario
resource
reservation;
slice
deployment)
(pre-
network
P2P
slice
and
MP2MP
slice
(on-
demand slicing)
Different resource reservation technologies can be used together, as shown in
Figure 6-5. Carriers usually use FlexE interfaces or channelized sub-interfaces to
reserve coarse-grained slice resources for specific industries or service types.
These are then further divided into Flex-channels to reserve fine-grained slice
resources for different enterprise users.
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Suggestions on Network Slicing Deployment
Figure 6-5 Combination of different resource reservation technologies
Network slices with hierarchical scheduling are used to provide flexible and
refined resource management. For example, on a network with 50 Gbit/s
bandwidth in the access ring and 100 Gbit/s bandwidth in the aggregation ring,
FlexE interfaces can be used on the access and aggregation rings to reserve 1
Gbit/s and 2 Gbit/s bandwidth, respectively. This implements hard isolation of
services and meets the requirements of a vertical industry on isolation and ultralow latency. After entering the aggregation ring from multiple access rings,
services in the same slice can share the 2 Gbit/s bandwidth reserved for the slice
in the aggregation ring. Different service types or users of the vertical industry
can continue to use channelized sub-interface or Flex-channel technology in a
FlexE interface of a slice to perform refined resource reservation and scheduling.
This maximizes statistical multiplexing of resources while meeting requirements
on slice isolation and SLA assurance.
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Suggestions on Network Slicing Deployment
Chapter 7
Successful Applications of
Network Slicing
Abstract
To meet differentiated SLA requirements in the 5G and cloud era,
carriers support different services through network slicing, helping
enterprises achieve digital transformation. This chapter describes the
successful applications of network slicing in four scenarios: smart
healthcare, smart policing, smart port, and smart grid.
7.1 Smart Healthcare — Slice-based
Healthcare Private Network
Requirement Introduction
As shown in Figure 7-1, smart healthcare is a healthcare service system that uses
network technologies to implement prevention, consultation, diagnosis &
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Successful Applications of Network Slicing
treatment, rehabilitation, health care, and more. During the promotion of smart
healthcare, high-speed broadband networks and interconnected private lines
covering urban and rural healthcare organizations are crucial for supporting the
smart healthcare system.
Figure 7-1 Different services of smart healthcare
To support cloudification and interconnection for services of hospitals at all
levels in urban and rural areas, as well as implement telemedicine anytime and
anywhere, the healthcare private network needs to have the following
capabilities:

Full-mesh connection: City-level tertiary A hospitals serve as centers and
establish hub-spoke interconnections with county-level hospitals. This
enables service channels to be quickly established between any two
healthcare organizations.

High bandwidth: The bandwidth of each village clinic and community health
station is increased to 300 Mbit/s. The bandwidth of township health centers
and community health centers is increased to 500 Mbit/s. The bandwidth of
the county-level or higher-level health and family planning commissions and
secondary and tertiary hospitals is increased to 1 Gbit/s.
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Successful Applications of Network Slicing

Ultra-low latency: Core healthcare systems are migrated to the cloud. The
service latency of systems such as image archiving & communication
systems and hospital information management systems is less than 20 ms
and remains stable, providing service experience the same as local services.
Smart Healthcare Based on Network Slicing
The "Healthcare Cloud Network" product provided by the network slice private
network can implement one network for multiple purposes, as shown in Figure
7-2.
Figure 7-2 Healthcare private network based on network slicing
This private network is the first in the industry to deploy slicing and SRv6
technologies across the entire network. It has the following characteristics:

Network slices for hard isolation: Resources of different slices are
independent of each other. The SLAs of services in a slice can still be
guaranteed, even if services in other slices are congested.
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Successful Applications of Network Slicing

Fast provisioning and agile O&M: NCE provides E2E network slice lifecycle
management, and slices and SLAs are visualized and controllable.

One network for multiple purposes: One healthcare private network can be
further sliced to provide multiple service slices, enabling one network for
multiple purposes and high Return On Investment (ROI).
7.2 Smart Policing — Slice-based
Public Security Private Network
Requirement Introduction
Public security systems face challenges such as insufficient police resources and
low law enforcement efficiency. With the 5G network, public security systems
can implement smart policing such as police drone, video surveillance, AR patrol,
and comprehensive intelligence command system, as shown in Figure 7-3. Smart
policing can implement ground-air multi-dimensional patrol within a jurisdiction,
making up for insufficient police resources and improving comprehensive law
enforcement efficiency.
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Successful Applications of Network Slicing
Figure 7-3 Different policing services of smart policing
To implement smart policing, the public security information network needs to
have the following capabilities:

High security and reliability: Uploaded policing surveillance data has high
security requirements and must be fully isolated from public data
transmission channels.

High bandwidth: Drone patrol, smart police cars, and high-altitude cameras
require 4K HD surveillance, and 4K video recording requires real-time
transmission (20 Mbit/s to 40 Mbit/s uplink bandwidth per channel).

Guaranteed latency: In the hotspot areas of B2C user traffic, E2E resource
reservation can be used to guarantee the latency of public security services.
Smart Policing Based on Network Slicing
E2E network slicing can be used to provide a private network for policing services
to meet the security isolation requirements of policing and public user services.
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Successful Applications of Network Slicing
Figure 7-4 Smart policing based on network slicing
The network slicing-based
characteristics:
smart
policing
solution
has
the
following

High security and reliability: An independent E2E channel for the policing
service slice is deployed, where Radio Bearer (RB) or Allocation and
Retention Priority (ARP) is deployed on the Radio Access Network (RAN) to
reserve resources; FlexE slicing is deployed on the IP network to reserve
resources; and a standalone UPF is deployed on the core network). This
isolates policing services from public services and ensures the security of
uploaded policing surveillance data.

High bandwidth: High-bandwidth slices are deployed (10GE for base stations,
50GE for the IP network, and 100GE for the core and aggregation layers) to
meet the upstream bandwidth requirements of videos and implement realtime uploading of multi-channel HD videos.

Guaranteed latency: FlexE slicing is deployed to implement hard pipe
isolation and guarantee the stable latency of policing services.

Visualized slice SLA: IFIT is deployed to visualize the SLA of service slices,
quickly locating network faults.
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Successful Applications of Network Slicing
7.3 Smart Port — Slice-based Port
Private Network
Requirement Introduction
The port industry is a heavy machinery industry. The main operation site of a
port is located in the outdoor yard, which occupies a large area and is covered by
containers, cranes, and container trucks, as shown in Figure 7-5.
Figure 7-5 Port area map
A gantry crane in the port is responsible for hoisting containers to a specified
position in the yard. A traditional gantry crane uses optical fibers or Wireless
Fidelity (Wi-Fi) to connect to the central control room for remote control. Before
the remote control reconstruction, the existing network of the port faces
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Successful Applications of Network Slicing
challenges such as high optical fiber costs, limited Wi-Fi coverage, difficult
production network isolation, and high labor costs.
With the advent of the 5G era, the port urgently needs to be upgraded to a
smart one. This requires gantry cranes to be reconstructed. If HD cameras can be
deployed on each gantry crane to upload HD videos to the control room,
workers can view the site through HD videos and remotely control the gantry
crane through low-latency channels. This resolves the above challenges while
meeting the requirements of the gantry crane.
To implement remote control and monitoring, the following capabilities are
required:

High bandwidth: Each gantry crane has 18 1080p cameras, and the required
uplink bandwidth is 30 Mbit/s.

Low latency: The required E2E latency is 18 ms, where the latency required
for the IP network is 3 ms.

High availability: 99.999% availability, less than one suspension per month.
Smart Port Based on Network Slicing
Remote control and remote monitoring have different network requirements.
The slice management system is used to deploy low-latency and high-bandwidth
slice-based private networks for remote control and remote monitoring. This
provides E2E SLA assurance at different service levels, effectively meeting the
remote operation requirements of gantry cranes.
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Successful Applications of Network Slicing
Figure 7-6 Smart port based on network slicing
The network slicing-based smart port solution has the following characteristics:

Low latency: A low-latency FlexE slice is deployed to carry control services.
This implements hard pipe isolation and meets ultra-low latency
requirements.

High bandwidth: A high-bandwidth slice is deployed to carry video services.
This meets uplink bandwidth requirements without affecting control services.

High reliability: Slices support fast rerouting and service switching within 50
ms.

Visualized slice SLA: IFIT is deployed to visualize the SLA of service slices,
implementing fault locating within minutes.
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Successful Applications of Network Slicing
Compared with traditional ports, smart ports that adopt remote control and
monitoring can cut labor costs by 75% and enable gantry cranes to move flexibly
and work unattended, reducing security risks.
7.4 Smart Grid — Slice-based Power
Grid Private Network
Requirement Introduction
China Southern Power Grid serves an area of over 1 million square kilometers,
covering more than 250 million people. China Southern Power Grid built a smart
grid on a communication network, leveraging sensing and measurement
technologies, device technologies, control methods, and decision-making support
systems to achieve reliability, security, cost-effectiveness, efficiency, and
environment-friendliness targets.
A smart grid involves two types of communication application scenarios: control
and collection. Control services include intelligent distributed power distribution
automation, demand response, and distributed energy control. Collection services
include advanced metering and big video applications.
Table 7-1 Electric power service scenarios
Service
Typical
Type
Scenario
Scenario Description
Control
Intelligent
Implements protection and control of the power distribution
distributed
network. By using automatic relay protection devices to
power
monitor the status of lines or devices on the power distribution
distribution
network, the system rapidly determines and accurately locates
automation
line segment or device faults, isolates the faulty segments or
devices, and then restores power supply in normal areas. This
scenario requires ultra-low latency and high reliability.
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Successful Applications of Network Slicing
Service
Type
Typical
Scenario
Scenario Description
Demand
Reduces or shifts the power load in a certain period when the
response
reliability of the power system is threatened, thereby ensuring
the stability of the power grid. This scenario requires ultra-low
latency and high reliability.
Distributed
Controls distributed energy forms, including solar energy
energy
utilization, wind energy utilization, fuel cell, and combined
control
cooling heating and power. Distributed energy resources are
distributed on the user/load site and adjacent sites. The
locations are flexible and scattered, and the number of
distributed energy resources is large. This scenario features
massive connections and real-time statistics collection.
Collection
Advanced
Performs
metering
information
in-depth
of
collection
smart
meters
for
to
power
meet
consumption
smart
power
consumption and personalized customer service requirements.
In this scenario, a large amount of data is frequently collected.
It features massive connections and real-time statistics
collection.
Big
video
applications
Includes substation inspection robots, drone patrol for power
transmission lines, comprehensive video surveillance for power
distribution rooms, and mobile management and control for
onsite construction activities, which require real-time video
and image
transmission.
As such,
high communication
bandwidth is required.
A smart grid has the following key requirements on a network:

Ultra-low latency: Intelligent distributed power distribution automation and
demand response services require precise control at the millisecond level.

Massive connections: The power distribution network has a wide coverage,
and a large number of smart meters and distributed energy resources are
deployed. This requires massive connections.

High bandwidth: Monitoring and inspection services require high bandwidth.
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Successful Applications of Network Slicing

High reliability: Video services require 99.9% availability, control services
require 99.999% availability, and production and management services need
to be isolated.
Smart Grid Based on Network Slicing
Smart grid services have a wide range of requirements. Slice services of different
networks can specifically meet the communication and transmission
requirements of a smart grid. As shown in Figure 7-7, different service scenarios
correspond to different network slice types.

The URLLC slice mainly includes intelligent distributed power distribution
automation and demand response services.

The mMTC slice mainly includes distributed energy control and advanced
metering services.

The eMBB slice mainly includes big video applications, such as substation
inspection robots and drone patrol for power transmission lines.
Multiple network slice instances can be created for each type of slice as required.
Power grid enterprises can provide differentiated electric power network slice
services based on the slice running status and service requirements.
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Successful Applications of Network Slicing
Figure 7-7 Smart grid based on network slicing
The network slicing-based smart grid solution has the following characteristics:

Intelligent slicing and guaranteed latency: MEC is deployed closer to users
on demand. FlexE technology is introduced on the IP network, ensuring that
its latency is less than 2 ms.

Security isolation: The IP network uses FlexE to reserve resources such as
physical and virtual logical resources for services in different zones of the
power grid, meeting different security isolation requirements of production
and management power services.

High reliability of slice services: Comprehensive protection mechanisms, such
as FRR, ensure high-quality bearing of power grid services.
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Successful Applications of Network Slicing
Chapter 8
Technical Prospects of
Network Slicing
In contrast to individual consumer services oriented to end users, industry and
enterprise users require a network that can provide deterministic service
assurance in terms of key indicators such as latency, jitter, and packet loss rate.
This means that network capabilities need to evolve from "one pipe, best effort,
and applications adapt to networks" to "differentiated connections, deterministic
assurance, and network matches applications." Network slicing is the most
important technical foundation for implementing the preceding capabilities.
Network slicing is a landmark technology in the 5G era. It opens the door to a
wide range of new industry applications and brings secure, reliable, manageable,
and controllable differentiated services with committed QoS to industry markets.
For carriers, network slicing helps them offer their network infrastructures to
various industries in a more flexible, efficient, and open manner. In addition, slice
isolation of different dimensions and degrees ensures high QoS, reliability, and
security of various services. Currently, carriers are actively cooperating with
industry partners, equipment vendors, and integrators to fully verify and
gradually put network slicing solutions and key technologies into commercial use
in multiple fields such as electric power, healthcare, industrial manufacturing,
transportation, video live broadcast, and cloud gaming.
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Technical Prospects of Network Slicing
For tenants in vertical fields and third-party Over The Tops (OTTs, providing
various application services for users through the Internet), network slicing
allows network resources and capabilities to be used more conveniently and
quickly, obtaining on-demand deterministic service assurance. Network slicing
will promote in-depth cooperation between tenants in vertical fields, third-party
OTTs, and carriers, and promote the emergence and development of new
business models and ecological environments.
Network slicing's requirements and related technologies start in the 5G era, but
its applications will not be limited to 5G. The concept, architecture, and technical
solutions of network slicing will be continuously verified and improved in more
extensive service scenarios. In addition, the continuous deployment and
application of network slicing will bring greater value to carriers, industry users,
and enterprise users.
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Technical Prospects of Network Slicing
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Technical Prospects of Network Slicing