Download One slice at a time: SDN/NFV to 5G network slicing

One slice at a time: SDN/NFV to 5G network slicing / Cutting Edge
One slice at a time:
SDN/NFV to 5G network slicing
The network modernization journey is one that every telco must take. NFV and SDN are the fuel, software
and cloud define the route, and customer experience sits waiting expectantly at the destination. Telcos
need to approach this transformative journey with three buzzwords in mind: agility, efficiency, and speed.
But, to be really effective, end-to-end (E2E) network-wide slicing needs to happen.
By Gary Maidment
Adapted from the white paper NFV/SDN to 5G Network Slicing by Dr. Ling Yim-Kwong
Fast, efficient, agile
T
the first mobile phone call in 1973.
and mobile tech really joined hands
Ten years later, Motorola rolled out
with the first smartphone from
he digital age has coalesced
the first commercial mobile phone,
Apple. A true game changer, this
extremely quickly from the
around a decade ahead of when the
gave birth to the world of smart
invention of the Internet
Internet became big in the early 90s.
phones and apps from OTT providers
as ARPANET in 1969 and
It wasn’t until 2007 that networked
that we know and love today.
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CUTTING EDGE
Regional
Cloud Factory
(Large
Operator)
Data Center
Cloudification
Tradition
Telecom
Network
NFV
New
Services
Service
Migration
SDN @ Wide
Area Network
SDN@Data
Center
Phase 1
Virtualisation & Cloudification
Phase 2
Service Migration
End-to-End
Orchestration
(Network &
Services)
Phase 3
Orchestration
Network Slicing
(Automation)
Phase 4
Service Network Slice
The four phases of NFV/SDN transformation
People’s appetite for apps and social
more efficient. They need to provide a
in. Additionally, it takes time for
networking has seen network traffic
better experience at lower CAPEX and
people to acquire the requisite skills
shoot up, a trend that will continue
OPEX. They also need to be agile, so
and for organizations to transform the
as new IoT services come into full
telcos can quickly innovate and roll out
way they work into this new software-
force for consumers and verticals.
the services that people want when
and customer-centric mode. There are
Up to 100 billion connections
they want them. Efficiency, agility, and
four phases involved in transformation
are predicted for 2025, with an
speed are set to become the hallmarks
(as shown in the above graphic).
estimated 8 billion of these coming
of success. And NFV and SDN are the
from smartphones.
tools for transformation.
However, a far more bullish
approach to construction is possible
However, profits for the telcos that
To best apply this tech, 5G networks
that compresses these phases and
run the networks that underpin
can be portioned into individual
works like this: Build a separate
the modern world are one of the
slices, where each has independent
NFV/SDN network, overlay it on the
few things that aren’t heading
characteristics for best delivering a
telco network, and migrate legacy
skywards. Ovum predicts that traffic
particular service type and sharing
services in one go. Despite the
on broadband networks will increase
resources between services and slices.
concertina effect that this approach
by 205 percent from 2015 to 2025.
In contrast, global spending on
broadband services will limp up by a
Take it one step at a
time?
comparatively weak 51 percent over
the same ten years.
Grand aims are one thing, but
implementation is another when
64
delivers, it’s still important to
understand each phase.
Phase 1: Virtualization
and cloudification
To stay profitable and meet traffic
legacy networks and the maturity of
Virtualization separates the hardware
demands, networks need to be made
the tech and ecosystem are factored
and software functions of network
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One slice at a time: SDN/NFV to 5G network slicing / Cutting Edge
elements (NE) like routers.
switches for data forwarding and
For example, each OpCo under
network control. SDN, however,
a multinational telco usually has
It reflects a shift towards software-
centralizes the control function in
its own national network and
defined functions based on advances
a single network controller – the
platforms. With optical fiber
in computing hardware, which allows
software-based SDN Controller.
reducing transmission costs,
computing power and storage to
Then, the network router and switch
it’s wise for multinationals to
be shared and offers far greater
only perform forwarding, cutting
consolidate multiple national
flexibility. Applications can run as
costs on the elements that forward
infrastructures into a cross-border
efficiently on commercial-off-the-
packets.
international infrastructure. This
shelf (COTS) hardware as they do on
specialist hardware.
concept – a common, unified, and
The SDN controller oversees a large part
converged platform – is referred
of the network and easily finds the best
to as a Regional Cloud Factory. For
Alongside virtualization, computing
routes for packets, which is especially
multinationals, it allows advantages
power and storage are shifting
useful when the network is congested
like running a single VAS platform
from PCs to a centralized cloud
or part of it is down. The controller’s
instead of one for each OpCo.
infrastructure that decouples
decision-making ability is far superior to
functionality and location.
traditional routing where routers and
Although synergy benefits for pan-
Advantages include scalability
switches make decisions based on a
European or pan-African cloud
and resource sharing, resilience,
limited network view.
factories are potentially huge, hurdles
low power use, and efficiency.
exist. These include regulatory
Centralizing large amounts of data
According to a Gartner report
constraints, data security, privacy,
for different uses from different
published in January 2016, only 2
local customization versus regional
users supports big data analytics
percent of its clients have deployed
content availability, and local versus
and its wealth of corresponding
SDN, with delays largely being
regional support. For example, some
applications.
attributable to a lack of standardized
services can be migrated to regional
equipment. For telcos, large-scale
centers, whereas others might be
NFV extends virtualization technology
deployment of SDN is still in its
best served locally.
to network infrastructure. NFV
infancy.
decouples the software functions from
Regional cloud factory
dedicated hardware, allowing Virtual
Phase 2: Service
migration
Network Function (VNF) software
National network architecture normally
to run on commodity-based servers,
comprises two or three layers, typically
There are several strategies for
which emulates an NE’s function and
including access, aggregation,
implementing NFV and SDN and
performance. Commercially available
and core. Cloud infrastructure is
migrating services from legacy to
products for doing this include vIMS
also arranged in layers, which are
new platforms. Each strategy must
and vEPC.
normally local, regional, and national
consider service criticality and the
SDN takes control
data centers. For both, layering is
interdependence of multiple services.
better for performance, scalability,
The main strategies are:
Common transmission networks
flexibility, resilience, maintenance, and
comprise dedicated routers and
consolidation.
New service deployment such as
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CUTTING EDGE
VoLTE with IMS and Bandwidth on
for agile SDN and NFV operations.
Each slice is optimized for a particular
Demand (BoD) services for enterprises.
Although early applications of EEO
service type and each is E2E,
are in place, such as China Telecom’s
including the RAN and core. Unlike
End of lifecycle updates where
Cloud VPN, the first release of
LTE, 5G air interfaces can be sliced
legacy hardware and software need
Open-O is scheduled for September
dynamically or semi-dynamically.
massive capacity upgrades, in which
2016.
Several concurrent network slices can
case it may be better to replace the
platform.
Phase 4: Network
slicing
Deploying a central SDN and NFV
infrastructure; for example, a critical
communications slice would provide
ultra-low latency channels while the
platform, which will allow big data
Existing traditional mobile networks
IoT slice would deliver a massive
analytics to provide new integrated
operate under a monolithic model
number of connections.
services.
where a single network carries out
Putting it all together
all services, with protocols such as
Unifying services to encourage the
DiffServ in IP prioritizing different
Network slicing is based on NFV
deployment of new, more efficient
services. But, the protocols tend to be
and SDN technologies. Both NFV
technologies.
piecemeal, not E2E.
and SDN need to be overlaid with
Phase 3: End-to-end
orchestration (EEO)
orchestration, on top of which
Network slicing is documented as
EEO is required to coordinate the
part of the NGMN's vision for 5G.
two. Telcos like China Mobile, DT,
The technology optimally arranges
KDDI, KT, NTT, and SK Telecom
As independent but complementary
network resources for maximal cost-
are making moves into slicing tech,
technologies, both NFV and SDN
efficiency to satisfy new and diverse
with NTT already developing a slice
can transform telco networks into
5G service demands. NGMN defines
management system – a key part of
software-based entities. But, network-
slicing as E2E, including on core and
the overall solution.
wide applications with EEO on both
access networks.
technologies are necessary for the
benefits to shine.
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be deployed on a common physical
The new 5G air interface supports
What can Huawei do?
network slicing. On a core network,
Huawei is a leading provider of
Orchestration yields the agility
network slicing can be implemented
NFV and SDN technologies and
for operators to allocate network
separately or ahead of the new 5G
continues to play a leading role in
resources efficiently and cut TTM.
air interface. Each slice is a logical
developing both. Providing products,
Of the several initiatives to achieve
self-contained network where a
solutions, and consultancy services
EEO across NFV and SDN, Open-
service runs on its own network
for operators, Huawei Consulting is
Orchestrator (Open-O) managed by
slice; for example, one slice could
adept at helping telcos transform
Unix Foundation is a key one. First
be for video, one for IoT, another
into the future – a future in which
announced at MWC 2016, Open-O
for critical communication, and so
SDN, NFV, and network slicing on 5G
is a collaborative effort that aims
on. But, it’s also possible to group
networks are poised to deliver service
to develop the first open source
multiple, similar services on one
rollout benefits that can greatly ramp
software framework and orchestrator
network slice.
up profitability.
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