5G: The Next Generation of Mobile Experiences Overcoming the challenges of 5G deployments, and maximizing the opportunities

1. 5G: The Next Generation of Mobile Experiences
Overcoming the challenges of 5G deployments, and
maximizing the opportunities
Ali Mohamed Ahmed, Ph.D.
Thursday, July 17, 2018

2. Executive Summary
5G enables new revenue streams from new mobile experiences, applications, and services. However these new applications and
services impose diverse and extreme requirements on the network for latency, throughput, capacity, and availability. The network
approach to meeting these extreme requirements should not result in either over-engineering it, where significant investments are wasted
or under-engineering it, where customer experience and competitiveness are negatively impacted. In other words, operators need a 5G
strategy that balances network investment, new revenue streams and competitiveness.
To do this right and to realize the full potential of 5G; a fundamental rethinking of the mobile network is needed. The network
architecture must be transformed from the current network of entities & connectivity architecture to a network of capabilities & services
architecture. However, to set the expectations, such network transformation is a complex and massive undertaking, involving many
stakeholders and complex systems. It cannot be done overnight, and does require careful implementation considerations taking into
account the implications on existing network and its future capabilities. One contributing factor to this complexity is the fact that 5G
enablers are in part disruptive technologies and in part evolutions of existing technologies. This is in contrast with previous wireless
generations (2G, 3G, and 4G), which are mainly evolutionary.
Some of the key 5G disruptive enablers include, but not limited to, Software Defined Network (SDN), Network Function Virtualization
(NFV), Self Optimizing Networks (SON), Network Slicing, Centralized-Radio Access Network (C-RAN), and Artificial Intelligence (AI).
Note that some of these enablers are not new, however they remain disruptive to existing technologies. These disruptive technologies
will allow for a high level of abstraction and automation that are necessary to deal with complex 5G systems and requirements,
therefore they must be considered for any 5G strategy/roadmap in addition to the evolutionary technologies such as, for example,
massive MIMO (Multiple Input Multiple Output), which is a prime enabler of 5G due to its data rate boosting capabilities.
This document provides a high-level comprehensive look at the 5G implementation challenges, including increased volume of traffic,
massive number of devices, huge increase in cell sites, mobility management issues, backhaul, spectrum, energy efficiency and security.
It also presents the opportunities created by the 5G disruptive and evolutionary technologies, including C-RAN, SDN, NFV, SON,
Network Slicing, massive MIMO, and the 5G NR (New Radio). Understanding these challenges and opportunities will help in setting up
the stakeholders expectations and steer the deployment of 5G towards practical, smooth, and successful implementation that scales and
balances the network investment, new revenue streams and competitiveness.

3. Massive increase in cell sites5
User mobility management4
Extreme backhaul requirements3
Extreme and diverse performance
requirements
2
Increasing volume of traffic and
devices1
Understanding these 10 key challenges and opportunities associated with them will help in setting
up the stakeholders expectations from the outset, and steer the deployment of 5G towards
practical, smooth, and successful implementation that scales and balances the network investment,
new revenue streams and competitiveness.
10 Key Challenges of 5G deployments
Automation requirements8
Low energy consumptions7
Spectrum harmonization &
availability
6
Security10
Availability of devices9
3

4. Average Internet User
Consumes 1.5 GB of
Data Per Day
Smart Factory
Consumption Per Day
Autonomous
Automobile Per
Day Each
~1.5 GB
Increasing volume of traffic and devices
1,000,000 GB
4,000 GB
3,000 GB
Smart Hospitals Data
Consumption Per Day
4
1
• Some of the 5G applications will be bandwidth hungry such as VR (Virtual
Reality), AR (Augmented Reality) and Gaming.
• Some will be lighter but in massive numbers such as IoT (Internet of
Things) services in various industry verticals (e.g. Automotive, Smart Cities,
E-Health, Energy, etc.).
• The above is on top of the usual Internet traffic that is growing at about 40
- 50% year over year (e.g. YouTube, Netflix, Facebook, etc.).
To provision for this increase in capacity and devices; Service Providers need
to invest in some or all of the following initiatives:
1- Network densification,
2- Improved spectrum efficiency,
3- Spectrum extension, and
4- Flexible network resources sharing (e.g. C-RAN).
• These initiatives involve technology features that are partly an evolution
of existing technologies (e.g. massive MIMO and HetNets) and partly
disruptive new technologies (e.g. C-RAN: Cloud/Centralized Radio Access
Network).
• Service Providers need to understand the complex trade-offs and
constraints associated with these technologies to set expectations and
avoid negative implications on their business objectives.

5. Extreme and diverse performance requirements
5
2
In order for the network to dynamically adapt to the these
extreme requirements imposed by large variety of industrial
vertical services and applications, a new concept is
introduced in 5G called Network Slicing:
• The Network Slicing is enabled in part by SDN (Software
Defined Networks), NFV (Network Function
Virtualization), SR (Segment Routing), and SON (Self
Optimizing Networks).
• Network Slicing is one of the key capabilities that will
enable the flexibility needed to efficiently meet these 5G
extreme and diverse requirements.
• Network Slicing allows multiple logical networks
representing multiple classes of services to be created on
top of a common shared physical infrastructure/network.
Data rate:
100 Mbps to 10 Gbps1
VR & AR with real-
2me cloud-based
graphics rendering
Latency:
less than 1 ms
(end-to-end)
4
Touch-screen/
Tac0le Internet
applica0ons
Latency:
tens of minutes, or
more
3 Smart meter
applica2ons
Depending on the use case, data rates could range from 1 kbps to 10 Gbps and latency
requirements ranging from microseconds to hours:
Data rate:
0.1 Mbps or less2 Fleet management
(tracking a vehicle)
Use Case Performance

6. Extreme backhaul requirements3
• The predicted growth of the small-cell sites (e.g. 1500 small-cells per square
km, including femtocells), in 5G, puts pressure on operators to find cost-
effective solutions for backhaul.
• These solutions must provide adequate backhaul performance in terms of
capacity, synchronization (time & frequency), and latency. Specifically, latency
requirements can be extreme depending on the architecture decisions taken.
• For example, if a Service Provider is to consider C-RAN architecture, which is
one of the key disruptive 5G technologies that is cost effective and provides
high resource utilization, it will impose a latency requirement of 150 μ sec on
the backhaul.
Service Providers need to be aware of the trade-offs between backhaul
choices and impact on RAN architecture (i.e. C-RAN vs. D-RAN) and
vice versa:
From practical point of view, it is
likely that there will not be one-
solution fits-all approach to backhaul,
but rather a heterogeneous backhaul
network.
Backhaul Network
( Fiber, Microwave, mmW,
xPON, xDSL, DOCSIS )
• Fiber & mmWave backhauls put no constraints on RAN architecture as they
can meet the extreme requirements of latency.
• C-RAN requires fiber or mmWave backhauls,
• D-RAN, on the other hand, relaxes the backhaul requirements opening up
opportunities for other backhaul solutions such as xPON, xDSL, and
DOCSIS.

7. User mobility management4
• Traditionally, users moving from one cell to another require handover
procedure managed by the Mobility Management Entity (MME) in the
Radio Access Network (RAN).
• If this model were applied to the 5G high-density small-cells network, it
would generate a crippling signalling overhead due to the frequent cell
border crossing as a result of the limited footprints of small-cells. This
brings a new challenge in the user mobility management.
• To help overcome this challenge; the network should be organized in
clusters of small-cells so that mobility handover is triggered only when
users move between clusters as opposed to between individual small-
cells.
• A key 5G technology enabling this type of cluster configuration is the
decoupling of data and control planes.
• The full separation of control plane allows control & user planes
resources to be scaled independently.
• Small-cells are used as data offloading points whereas mobility handover
is handled in the decoupled control plane at the cluster level (e.g.
Anchored macro Base Station).Control Plane via Macro-cell
Data Plane via Small-cell
Small-cell
Macro-cell
Macro-cell
Control & Data via Macro-cell
Traditional Macro-Cell
5G Hetnet Split

8. Spectrum harmonization & availability5
• Spectrum harmonization, especially when achieved early in
the process, enables 5G-network gear production, end-
devices availability, network field trials, deployments, and
roaming.
• 5G will use low frequencies (below 1 GHz, good for coverage
in rural areas), high frequencies (above 1 GHz and below 6
GHz, good for high data rates and coverage in urban areas),
and very high frequencies referred to as millimetre wave
(mmWave) frequencies (above 6GHz, good for ultra high data
rates and wireless backhaul).
• Owning a spectrum mix of all of these frequency bands
provides flexibility and tools for Service Providers to manage
coverage, data rates, capacity, and power consumption.
• The 3.5 GHz band in particular is very strategic, in that it can
be used in both macro cell and microcells settings, thanks to
the latest technological advancements in antenna and signal
processing. Therefore, it is probably the only credible 5G band
for deployments taking place before 2020.
Source: IEEE COMMUNICATIONS VOL. 18, NO. 3
Next Generation 5G Wireless Networks: A Comprehensive Survey, Mamta Agiwal, Abhishek Roy,
and Navrati Saxena

9. Massive increase in cell sites6
• To satisfy demand and enable meaningful
5G deployments, estimates indicate at
least 10 small cells per macro base
station in urban settings.
• 5G will require new antennas that are
compatible with the new 5G frequency
bands.
• Additional new sites will have to be
found to install small-cells in semi-
elevated locations. This is one of the
major challenges facing any operator
planning to deploy 5G at scale.
• Service Providers may have to consider
installing them on urban fixtures and
infrastructures such as, for example, bus
shelter, lampposts, billboards, and public
buildings.
• One key challenge will be to get timely
civil-work permissions from public
authorities, to install the antennas on
public fixtures.
Source: Small Cell Forum (SCF): ” SCF and the GSMA recommend adoption of the installation
classes specified by the IEC 62232 Ed 2.0 standard that are applicable to exposure limits based
on international guidelines (ICNIRP). Adoption of these harmonized and simplified rules by
regulators and policy makers will reduce administrative overheads for both planning authorities
and mobile operators. Regions using the IEC installation classes will benefit from expedited
small cell deployment and the social and economic benefits of enhanced mobile broadband
for all.”

10. Reduce Carbon Footprint Reduce Energy Bills Extend Device Battery Life
Current wireless communication
systems are mainly powered by
traditional carbon-based energy
sources. The scale of 5G would
require more sustainable energy
sources that minimize the
contribution of wireless systems
to the world’s CO2 emissions.
Current wireless networks are
designed to maximize the
capacity, in part, by scaling up
the transmit powers. However,
with the scale of 5G; such
approach will not be sustainable
as this will result in very high
operating costs (OPEX).
Studies show that 5G frame
structure microsleep provides 20%
energy savings when compared to
LTE. Also the Discontinous
Reception and Transmission modes
could add up to 80% savings
depending on traffic pattern. These
features should extend battery life.
Energy efficiency in 5G is an important requirement driven by the desire to:
10
Low energy consumptions7
Service Providers need to look at 5G systems holistically and have strategies on how to minimize the energy consumption while
maintaining a high network availability/up-time. A good starting point would be for Service Providers to look at the systems that
contribute the most. For example, studies on energy consumption of wireless communication systems have shown that backhaul
would contribute about 50% of the energy consumption.

11. The existing network operating model is overly
dependent on manual configurations and
manual interventions, which is a non-starter
for 5G, even if it is semi-automated. The sheer
number of required computations and
connections will overwhelm the existing semi-
automated processes.
11
Automation requirements8
Meeting these new 5G challenges
will require Service Providers to
embrace full-automation as a critical
component of their 5G-network
management strategy.
The emergence of 5G network slicing and the
dynamic provisioning of numerous virtualised
networks and components to meet various use
cases, bring new challenges to all aspects of
network management, including operation,
administration, and maintenance.

12. Potential Deployment Strategies
Strategy Analytics, in its newly published report,
finds that while the first 5G commercial handsets
will go on sale from early 2019, sales will not
begin to scale up until 2021 when volumes
approach 5% of global handset sales. Volumes in
2019 will be in just the millions, and only barely
in the tens of millions in 2020 according to
Strategy Analytics report.
12
Availability of devices9
Service Providers should not wait for
devices and must take advantage of the
1 2 – 1 8 m o n t h s w i n d ow o f
opportunity, offered by lack of devices,
to define realistic & competitive 5G-
network deployment strategies.
4 5G stand-alone (Using 5G core)
3 5G non-stand-alone (Using LTE core)
2 4G+5G (deploy new 5G-network technology,
adding to the existing 4G capacity)
1 4G only (business as usual)

13. Many of the 5G key enabling technologies
are software-defined such as SDN, NFV,
SON, etc. While this brings many benefits, it
also comes with security issues. Specifically,
decoupling of control plane from the user
plane, which is critical concept for SDN &
5G, brings some security vulnerabilities.
13
Security10
Service Providers must develop a rigorous
security strategy. Such strategy should include
active participation of various players involved
with the manufacturing, development, and
deployment of IoT devices. This is because
taping the expertise of individual verticals is
vital for an effective security system, as each
industry has its own use cases, and the impact
of the security issues vary from one industry to
another.
Other security challenges will come from the
IoT space. For example, cheaply made
consumer IoT devices could create security
problems for critical network infrastructure if
not properly secured. It is therefore essential
to make sure these cheap consumer IoT
devices have the right level of security, in
order for them not to become a vehicle for
hackers to attack networks and critical
infrastructures (e.g. Energy grids, Automotive,
Smart Cities, E-Health, etc.).

14. Epilogue
This presentation demonstrates , in sections 1 through 10, that 5G will be far more than just a new radio access
technology. Its architecture will expand to multiple systems and new concepts bringing with them new challenges
and opportunities. To overcome these challenges and seize the opportunities, the network transformation must be
planned properly and employs the right set of technologies and architectural trade-off decisions that take into
account practical and real operational constraints.
While the document provides a flavour of what decisions and trade-offs must be made in light of general practical
& real operational constraints; it is neither comprehensive nor specific to a Service Provider’s constraints and
realities. For example, in reality, the required backhaul bandwidth, in a C-RAN architecture, depends on many
factors such as actual aggregate carrier bandwidth used, cell load, the number of sectors, modulation & coding
scheme, and the number of antennas. Similarly, network slices design has to consider the specific radio access type
(RAT) that supports the network services provided by the slice, the configuration of RAN resources to appropriately
interface with and support the network slice, etc.
Further engagement is required in order for a Service Provider to carry out a full blown study to determine the
scope of technologies covered here, to get precise details about the trade-offs, and then decide on practical design
approaches that take into account the Service Provider’s specific constraints, resources, and capabilities.
If interested, please feel free to get in touch with me if you need to define a comprehensive and detailed 5G
strategy that will ensure a successful network transformation and overcome many of the challenges presented here.

15. Copyright © 2018, Dr. Ali Mohamed Ahmed
All rights reserved. All content in this document, such as text, graphics, logos, button icons and
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presentation of all materials in this document (including information in the public domain), and
the overall design of this presentation is the exclusive property of Dr. Ali Mohamed Ahmed. No
part of this document may be reproduced, distributed, or transmitted in any form or by any
means, including photocopying, recording, or other electronic or mechanical methods, without
the prior written permission of the Author.
This presentation is a synopsis of the white paper I wrote on “5G challenges & opportunities”
from the operator’s perspective. Please feel free to contact me through my LinkedIn profile
below to get a copy of the complete-paper if you are interested.
www.linkedin.com/in/alimohamedahmed