Page 185 - ITU-T Focus Group IMT-2020 Deliverables

ITU-T Focus Group IMT-2020 Deliverables 3

9.4 Scenario 4: Network Slicing

In IMT-2020 networks, it is necessary to consider end-to-end application quality and enablement through
network softwarization platform. Therefore, the current SDN and NFV technology should be utilized to
transform the infrastructure to realize end-to-end slice management and orchestration. Especially network
slice can be deployed and managed across the E2E network including Fronthaul/Backhaul Network, IP
Transport Network, Access DC, Regional DC and Core DC.

Figure 9.4-1 – Framework of network slice management and orchestration

Based on the existing network management (Network Function Management) and resource management
(Resource Management and Orchestration) in NFV/SDN, slice Management and Orchestration will be
introduced in network slicing. There are three scenarios that Slice Management and Orchestration should be
considered.
Network function management is responsible for FCAPS management of IMT-2020 functions, which can
include OSS, EMS and VNFM.

Resource management and orchestration is responsible for global and multi-domain resource management
and orchestration. Multi domains include Fronthaul/Backhaul network domain, IP network domain, and data
centers domain. It can combine multi-domain (i.e. Fronthaul/Backhaul network, IP network and DCs)
resources to meet the resource requirement of an E2E network slice instance, and assign necessary resource
to the slice instance, global resource monitoring, and global resource management and coordination.
Management and orchestration of Fronthaul/Backhaul network, IP network resources can be achieved by
SDN technology (i.e., introducing SDN controllers). And management and orchestration of resources in DCs
can be realized by NFV technology (introducing NFV MANO, VIM, VNFM). Resource management and
orchestration can communicate with orchestrators (e.g., NFVO) of access DC, regional DC and core DC to
initiate or deploy different network functions in different DCs according to the service requirement of a
specific network slice instance, and communicate with controllers of other domains (IP and transport
domain) to meet the instantiation and SLA requirement of the slice instance.

Prioritization mechanism on multiple slices can be supported by slice management and orchestration based
on the SLA of the requested slice and level of customers, e.g., the prioritization of deploying/scaling the slice
especially when the resources is not enough.
Scenario 1: Network slice design

Slice Management and Orchestration can support to select network functions and network topology to
design one network slice template with different network slice functions to cater for different types of
scenarios, e.g. eMBB/MTC/CC. Basic slice template with basic functions can be identified.

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