Network Function Virtualisation

Aakarshan Singh et.al. Int. Journal of Engineering Research and Application www.ijera.com
ISSN : 2248-9622, Vol. 7, Issue 4, ( Part -6) April 2017, pp.85-95
www.ijera.com DOI: 10.9790/9622-0704068595 85 | P a g e
Network Function Virtualisation
Aakarshan Singh1
, Kamal Grover2
, Palak Bansal3
, Taranveer Singh Seekhon4
1
Department of Electrical and Computer Engineering University of Ottawa Ottawa, Ontario
2
Department of Computer Science and Engineering National Institute of Technology Jalandhar, India
3
4
ABSTRACT
This paper is written to give basic knowledge of Network function virtualisation in network system. In this
paper the work on NFV done till now has been collaborated. It describes how the challenges faced by industry
lead to NFV and what is meaning of NFV and NFV architecture model. It also explains NFV Infrastructure is
managed and the forwarding path on which packets traverse in NFV. A relationship of NFV with SDN and
current research ongoing on NFV policies is discussed.
Index Terms: NFV, SDN, Communications
I. INTRODUCTION
A. Motivation
Over the past decades the communication
networks are growing at a rapid pace but to launch a
new network service we require money to buy
hardware, power to run them and space to keep these
machines. These hardware reach to end of life early
without much usage, this reduces innovation and
revenue made by networking. NFV addresses this
problem by using virtualization technology in
servers, switches and storages [1]. It changes the
network architecture by transferring hardware
network functions to a software. By this way it
reduces cost for equipment and power required to
run it. NFV is portable on any data plane and control
plane in fixed or mobile infrastructure [2]. More
over NFV gives targeted service, based on different
geography we can scale it up or down. This paper is
divided into 6 sections. The first section describes
how the challenges faced by industry lead to NFV
and what is meaning of NFV. In second section NFV
architecture model is defined. Third section talks
about how NFV Infrastructure is managed and the
forwarding path on which packets traverse in NFV.
In fourth section mentions relationship of NFV with
SDN, Further fifth section talks about use cases of
NFV. In last section, we tell what current research
ongoing on NFV policies is and work done till now.
B. Definition of NFV
”Network Functions Virtualization, or
NFV, is a network architecture philosophy that
utilizes virtualization technologies to manage core
networking functions via software as opposed to
having to rely on hardware to handle these
functions” [2]. These functions imitate host
functions and run on virtual machines. The NFV
concept is based on building blocks of virtualized
network functions, or VNFs, that can be combined to
create full-scale networking communication
services. NFV is designed to consolidate and deliver
the networking components needed to support a
fully virtualised infrastructure- including virtual
infrastructure, servers, storage, and even other
networks. It utilizes standard IT virtualisation
technologies that run on high-volume service, switch
and storage hardware to virtualise network
functions. NFV is applicable to any data plane
processing or control plane function in both wired
and wireless network infrastructures.
C. Literature Review
Network Functions Virtualisation Industry
specification group was founded under the European
telecommunication standard institute. It is global
organisation which gives open environment to
progress this work. It is a platform to address the
problems for NFV implementation and to encourage
the growth of open ecosystem [3]. ETSI has made
excellent progress and developed high level
reference documents like NFV infrastructure,
architecture, and use cases and NFV white papers.
These documents give the information about
ongoing progress on NFV and guides industry. SDX
central has resources which gives information on
NFV [4]. It says NFV offers a new way to design,
deploy and manage networking services. It
decouples network functions like network address
translation, firewall, and intrusion detection from
hardware appliances so that these functions can run
on software. Alcatel-lucent offers complete NFV
architecture that has NFV platform built to address
demands of service providers and gives SDN
technology that supports network automation and
RESEARCH ARTICLE OPEN ACCESS

abstraction. TechTarget provides the sources for
NFV, how it simplifies network chain provisioning,
SDN and NFV relationship and various NFV
strategies for mobile vendors [5].
II. NFV ARCHITECTURE
Virtual network functions run on a
framework called Network Function Virtualisation
Infrastructure. It includes diverse physical resources
and how can they be virtualised [6].NFV
architecture includes the functionality which is
required to virtualise the network functions , then to
run these functions on NFVI and manage them using
NFV specific management and orchestration.
A. Virtualisation
Every network function is defined in form of
functional block. It is implemented by configuring
the host functional block. The interaction between
these blocks is called interface. The functional block
contains host function and Virtualised network
function. The interface between two network
function is divided.VNF is dependent on host
function fig II.1. Specification of functional blocks
include a transfer function which is a predefined
transition matrix which mapped a specific tuple of
input and current state to a specific value of next
state and output. The functional block includes host
private state, configured state and virtual dynamic
state. These states allows virtual function to be
defined in functional block.VNF is an abstract view
of the host function. This configured VNF then can
be installed on different VMs to perform virtual
functions.
Fig. II.1. Virtualisation [6].
B. NFV Infrastructure
”NFV architectural framework includes
functional blocks and reference points in NFV
framework” [7]. NFVI is total hardware and
software component on which VNFs can be
deployed, managed and executed [7]. This
infrastructure can span around the locations by using
NFVI-Pops. The network connectivity between
these locations are part of NFV infrastructure. The
owner decides which functions should be
virtualised. Physical hardware resources include
computing, storage and network that provide
processing, storage and connectivity to virtual
network functions through virtualisation layer. A
software called hypervisor is installed on these
physical resources which creates them as virtual
machines. This creates virtualisation layer on which
virtual network functions are executed. In order to
manage the complexity and scalability of
infrastructure it NFVI is partitioned into three
separate domains. The interfaces between them are
reasonable. NFVI supports continued open supply
between these domains. Three primary domains are
as follows:
1) Compute Domain: It consists of high volume
storages and servers. It provides the COTS
computational and storage. It reduces the hardware
equipment cost and reduce power consumption.
Storage in compute includes CPU register, CPU
cache, volatile RAM and non-volatile block storage
[8]. In this domain processor instruction set is
executed by compute node which is a functional
entity capable of executing instruction set in such a
way that execution time is less. It accelerate packet
forwarding, switching and encryption.
2) Hypervisor Domain: It mediates the computer
resources to the virtual machines. It can emulate
every single piece of hardware. For example it
emulates CPU such that CPU instruction set
believes that it is running on completely different
CPU. Sometimes there can be performance hit in
these cases. To improve this CPU core is

exclusively allocated to VMs, direct memory
mapped polled drivers are used for VMs and v
Switch is implemented to provide connectivity
between VMs [9]. NFV hypervisor architecture is
used to improve performance and provide
orchestration and management.
3) Infrastructure Network Domain: It consists of
Consists of high volume switches interconnected
into a network which can be configured to supply
infrastructure network services. It provides
communication channel between different VNFs,
VNF and orchestration and management and
components of NFVI [10]. It also gives mean to
remotely deploy VNFCs. It basically gives
connectivity services. It will provide addressing
scheme and help in bandwidth allocation process.
Figure II.2 illustrates the application of principle
domains to NFV and how particularly it works in
NFVI. The three domains are maintained as separate
domain in NFVI. Management and orchestration
functions are hosted in NFVI as VMs and are placed
on container interface. In figure 2.2 Container
interfaces 1 are provided by VNFI to host VNFs.
VNF interconnect interfaces 2 connect Virtual
network functions with each other. VNF
Management and Orchestration Interface 3 connects
VNF to management services. Interface between
existing networks 4 and infrastructure domain is
lower layers of protocol.
Fig. II.2. NFV Infrastructure with it’s domains [7].
III. NFV SERVICE CHAIN AND MANO
A. Service chain
A Service chain is made up of network
services like application delivery controller,
firewalls. These services are interconnected to
support an application. Service chain can made
shorter and simpler when implemented with SDN
and NFV. In the past, building a service chain to
support a new application took a great deal of time
and effort. It meant acquiring network devices and
cabling them together in the required sequence. Each
service required a specialized hardware device, and
each device had to be individually configured with
its own command syntax.”The chance for error was
high, and a problem in one component could disrupt
the entire network” [11]. however two recent
development SDN and NFV, now enable network
managers to quickly and inexpensively create,
modify and remove service chains
B. NFV Management and Orchestration
NFV orchestration has unique requirements
based on the need to automate the highly dynamic
delivery of virtualized network services based on
service intent, compared to traditional orchestration
for services on physical appliances. The
requirements for NFV orchestration include rapid
configuration, provisioning, and chaining of virtual
network functions in addition to other resources
required for the service [12]. The ability to chain
VNFs together is an important and differentiating
feature to create innovative and customized services.
Second, intelligent service placement, Selection of
an optimal physical location and platform on which
to place the virtual network functions, depending on
various business and network parameters such as
cost, performance, and user experience, is a benefit.
A Virtual network function can be placed on various
devices in the network e.g. in a data center, network
node, or on the customer premises. Third, dynamic
scaling that involves the orchestration process maps
the instantiation of virtual network functions against
real-time demand. The capability of dynamically
scaling, frees up physical capacity to be used for
other services. Service providers use their
infrastructure more efficiently. They can also
achieve a more optimized return on investment by
deploying additional network services without
additional equipment costs.

Lastly, full lifecycle management of the
VNFs: This management includes the creation,
instantiation, and monitoring of the VNF until it is
decommissioned. Their are certain management
challenges associated with the decoupling of a VNF
from the hardware resources. ”Such challenges
include allocating and scaling hardware resources to
VNFs, keeping track of VNF instances location, etc.
such decoupling also presents challenges in
determining faults and correlating them for recovery
over the network. In order to perform its task, the
NFV management and orchestration should work
with existing management systems such as
OSS/BSS, hardware resourcemanagement system”
[13]. NFV Infrastructure include compute: that has
host or bare metal machines, virtual Machines as
resources that comprises CPU and Memory. It also
include volumes of storage at file system level .
Networking component include Ports, addresses and
forwarding rules, that ensures intra- and inter- VNF
connectivity. ”Aspects of VNF include traditional
FCAPS that is Fault management, configuration,
accounting, performance and security It Instantiates
network service by creating a network service using
NS on-board artefacts. It creates, deletes, query, and
update of VNF forwarding graphs associated to
Network Service and terminate them. Other
Management and orchestration aspects include Fault
and performance management, Policy Management,
Testing aspects of Network Services. MANO that is,
Management and orchestration function that
manages the overall functionality of virtual network
functions includes NFV Orchestrator (NFVO),VNF
Manager (VNFM),Virtualized Infrastructure
Manager (VIM), and a group of repositories .The
traditional Element Management (EM) and
OSS/BSS. The latter two blocks are not directly part
of the MANO, they exchange information with
MANO [13].
Fig. III.1. VNF Management and Orchestration [13].
1) NFV Orchestrator (NFVO): The NFV
Orchestrator has major responsibilities of
Orchestrating the NFV infrastructure( NFVI)
resources across multiple VIMs, fulfilling the
resource Orchestration. Secondly, lifecycle
management of network services thus fulfilling the
network service orchestration functions. Resource
orchestration:NFVO coordinates, authorizes,
releases and engages NFVI resources among
different PoPs (point of presence) or within one
PoP. It engages with the VIMs directly through their
north bound APIs instead of engaging with the
NFVI resources, directly. Resource orchestration
function of the NFVO is responsible for global view
of the network characteristics of the various logical
links. Service Orchestration: Service Orchestration
overcomes the challenge of creation of an end to end
service among different virtual network functions. It
coordinates with the respective VNFMs so it does
not need to talk to VNFs directly. E.g. would be
creating a service between the base station VNFs of
one vendor and core node VNFs of another vendor.
Service Orchestration can instantiate VNFMs on
requirement. It does the topology management of
the network services instances (VNF Forwarding
Graphs) i.e. creation, updation, query, and deletion
of VNF Forwarding Graphs. NFVO acts like a glue
in NFV that binds together different network
functions and creates an end to end service and
resource coordination in an otherwise dispersed
NFV environment.
2) Virtualised Network function manager-
VNFM(s): VNF manager is responsible for
lifecycle management of VNF instances of
instantiation, updation, scaling, and termination. A
VNF Manager can assigned the management of a

particular VNF instance, or also management of
multiple VNF instances. Most of the VNF Manager
functions are assumed to be common functions
applicable to any type of VNF but other
functionalities also includes VNF instantiation, of
VNF configuration if required by the VNF
deployment template.VNF instance software
updating or upgradation, VNF instance
modification, like scaling up/down of virtual
instance. Coordination of VIM and the Element
manager is responsibility of VNFM. A VNF
Manager maintains overall coordination and
adaptation for event reporting.
3) Virtualised infrastructure manager (VIM):
VIM manages NFVI resources in one domain that is
there may be multiple VIMs in an NFV architecture,
each managing its respective NFV Infrastructure
(NFVI) domain. NFVI is the NFV Infrastructure
that includes physical (server, storage etc.), virtual
resources (Virtual Machines) and software resources
(hypervisor) in an NFV environment). A VIM may
handle different types of NFVI resource like
compute, storage and network, or may be capable of
managing multiple types of NFV Infrastructures like
storage, networking resources etc.VIM is
responsible for Orchestrating the allocation,
upgradation, release of NFVI resources. It manages
life cycle of virtual resources in an NFVI domain.
That is, it creates, maintains and tears down virtual
machines (VMs) from physical resources in an
NFVI domain. It keeps north bound APIs and thus
exposes physical and virtual resources to other
management systems. It also provides northbound
interface to the higher layers like NFVO and VNF
Manager. Virtual Infrastructure manager is
responsible for the inventory information and
management of NFVI hardware resources like
compute, storage and software resources e.g.
hypervisors. From NFVs point of view, VIM
comprises the functionalities that controls and
manages the network function with computing,
storage and network resources and their
virtualisation.
4) Repositories: Repositories are like files or lists
that holds different information in NFV MANO.
There are four types of repositories VNF Catalog is
a catalog of all usable VNF descriptors. ”A VNF
Descriptor (VNFD) is a deployment template which
describes a VNF in terms of its deployment and
operational behavior requirements. It is primarily
used by VNFM in the process of VNF instantiation
and lifecycle management of a VNF instance. The
information provided in the VNFD is used by the
NFVO to manage and orchestrate Network Services
and virtualized resources on NFVI” [13]. Network
Services (NS) Catalog of the usable Network
services services. A deployment template for a
network service in terms of VNFs and description of
their connectivity through virtual links is stored in
NS Catalog for future use. NFV Instances list holds
all details about Network Services instances and
related VNF Instances. NFVI Resources repository
holds list of NFVI resources utilized for the purpose
of establishing NFV services. The Element manager
and OSS management systems are not part of NFV
MANO but they exchange information with NFVO
MANO functional Blocks. Element Management
(EM is available, if it needs to coordinate with
VNFM. it is responsible for the FCAPS (Fault,
Configuration, Accounting, Performance and
Security management) of VNF. VNFM does the
same job, but EM does it through proprietary
interface with the VNF in contrast to VNFM. EM
exchanges information with VNFM through open
reference point (Ve-Vnfm-em). OSS/BSS include
collection of systems-applications that a service
provider uses to operate its business. The existing
OSS/BBS, however, can value add the NFV MANO
by offering additional functions if, are not supported
by a certain implementation of NFV MANO. It is
done via an open reference point (Or-Ma-NFVO)
between NFV MANO and OSS-BSS.
C. VNF Instantiation flow
Fig. III.2. Instantiation flow [13].

Figure III.2 provides a high level picture of
a VNF instance instantiation request by an
application. ”NFVO receives a request to instantiate
a new VNF. This request might come from an OSS,
commissioning of a new VNF or part of an order for
a Network Service instantiation, or might come from
the VNF Manager when the need to instantiate a
new VNF is detected by the VNF Manager itself or
by the EM. Thus the Sender in the diagram can be
the OSS or an application. NFVO receives a request
to instantiate a new VNF using VNF lifecycle
management interface. it validates the request and
calls VNF manager to instantiate the VNF. The VNF
Manager validates the requests and processes it
further requesting NFVO for resource allocation.
NFVO requests allocation of resources to the VIM,
needed for virtualization deployment. VIM allocates
the internal connectivity network and allocates the
needed VMs and storage resources and attaches
instantiated VMs to internal connectivity network.
Acknowledgement of completion of resource
allocation is sent back to NFVO. NFVO then
acknowledges the completion of resource allocation
back to VNF manager”[13]. The NFVO
acknowledges the completion of VNF instantiation.
IV. RELATIONSHIP OF SDN AND NFV
As shown in figure IV.1, NFV is highly
complementary to SDN, but not dependent on it (or
vice-versa). Virtualisation of Network functions can
be implemented without SDN being required,
although the two concepts and solutions can be
combined Network Functions [14]. Virtualisation
goals can be achieved using non-SDN mechanisms,
relying on the techniques currently in use in many
datacentres. But approaches relying on the
separation of the control and data forwarding planes
as proposed by SDN can enhance performance,
simplifying compatibility with existing deployments,
and facilitating operation and maintenance
procedures. NFV can support infrastructure on
which SDN software can run.
Fig. IV.1. Relashionship of SDN, NFV and Open Inovation [14]
A. Collaborating SDN and NFV
ESTI gives out some ways by which NFV
and SDN can complement each other. According to
them SDN controller resembles NFV controller.
SDN help in orchestration of NFV resources by
providing functions like provisioning,
configuration of network connectivity, bandwidth
allocation, automation of operations, monitoring,
security, and policy control. SDN controller can
implement forwarding graphs by providing
automatic provisioning of service chain and ensure
security [15]. SDN controller overall can run as
virtual network function and become a part of
service chain for example all services and
application of SDN controller can be virtualised
and implemented as a separate VNF.
B. Joint Deployment
Open Networking foundation purposes a
model for jointly deploying multiple SDN and
NFV domains which requires explicit SDN-NFV
domain manager. SDN needs to know functionality
of available VNF and how to connect them to data
plane services and access them for control. Some
parts of NFVI may be dedicated to NFV domain
while other may

Fig. IV.2. Deploying SDN and NFV Controllers [15].
be particularly for SDN. NFV and SDN must
coordinate their claim to shared resources or
dynamically on packet by packet basis. Figure IV.2
illustrates how this might work. SDN controllers may
be both servers and clients to NFV domain [16]. At
the top of the figure, high order clients request
network services from SDN controller. SDN
controller satisfies this service request by
provisioning service-specific attributes into its
available resources for example NFV network
services. SDN controller can and should invoke
operations from the NFV discipline to create or scale
the necessary resources. In this figure resource
request push through the SDN do-main. It is equally
possible these requests can be set to NFV manager at
first and it instantiate VNFs which invokes SDN
controller.
V. USE CASES NFV
aims to transfer the way how network operator
architects network and virtualise network functions
and nodes. It can be used in service models and
applied to meet few challenges of network. NFV
gives the way of rapid innovation through software-
based deployment and operational network
functions.The following are use cases of NFV as
given by ETSI [17].
Fig. V.1. Use Cases of NFV [17].

A. Use Case1: NFV IaaS
NFV infrastructure as service functions
similarly as cloud Iaas does. It can orchestrate virtual
functions that compose virtual and physical network
and performs storage and compute functionality.
NFV IaaS is built on ETSI NFV standard interfaces
unlike traditional IaaS. NFV IaaS would also
compose of an information model and network and
network services interfaces that will allow NFV
Infrastructure to span the administrative domains of
multiple service providers.
B. Use Case2: Virtual CPE
Internet service providers spend huge sum of
money to procure and install consumer premises
equipments or access point routers. NFV allows ISP
to replace existing proprietary CPE with a
virtualization platform running on commercial of the
shelf servers that can be configured from a central
console and that can dynamically add and run new
services. Onpremises virtual access points will
increase new sales opportunities in competition to
market competitors and will drastically reduce capital
and operational expenditure. NFV management and
orchestration gives the ability for CPE platform to
run and manage multiple number of virtual network
functions. However, accessing VNFs remotely would
require significant bandwidth and in densely
populated residential areas would require massive
processing power and need for development of
methodology in which multiple VNFs could share a
single virtual machine.
C. Use Case3: VNPaaS
”The Service provider can make available a
suite of infrastructure and applications as a platform
on which the Enterprise can deploy their network
applications” [17]. In this form consumer deploy his
own application using this platform. It controls this
deployed application not underlining network.
VNFPaas provides a large scale service to enterprise
for examples it gives away whole virtual network. It
gives capability to consumer to make their own VNF
instances. Services like firewall or a whole business
communication can be deployed on these virtual
platforms. Basically service provider will give out
capabilities which gives ability to instantiate,
configure selected VFN and develop applications on
virtual machines.
D. Use Case4: VNF Forwarding Graph
VNF forwarding graph provides logical
connectivity between virtual appliances. VNF FG can
also interconnect with physical network functions to
provide network service. These forwarding graphs
provides efficiency, Resiliency and Flexibility when
used to connect physical appliances. Figure V.2 gives
example of VNF FG that service provider can use. In
this example, a network service is established
between two physical network function that has
VNF. In network services, many packets traverse
through VNF FG. Logical VNF FG maps physical
elements and their relationships. The service
provided will be able to judge the expected nature of
endend services and then understand effect of
abstract network functions in physical infrastructure.
Fig. V.2. Deployemnt of different Forwarding graphs by service provide [17].
E. Use Case5: Virtualisation of Mobile Core
Network
Mobile networks uses many hardware
appliances. Network function virtualisation aims at
reducing cost of these hardware, complexity and
increasing network operational efficiency. By
virtualisation, network topology can be changed to
optimise performances and increase elasticity of
network. Evolved Packet Core of cellular network
architecture has network functions like MME,S/P-
GW. This use case aims at virtualising EPC, IP
Multimedia subsystem, HSS , PRF etc. VNFs can be
scaled independently based on requirements.

F. Use Case6: Virtualisation of Mobile Base
Station
Mobile network traffic is significantly
increasing. In this scenario radio access part of
Evolved packet system has to fulfil requirements of
high peak data rate, ensure short round trip
frequency flexibility in radio access network. RAN
nodes in mobile network significantly accounts for
operational cost and energy consumption.
Virtualising mobile base station will transfer
functions of RAN on servers and switches which in
return will lead to dynamic resource allocation by
sharing multiple logical RAN nodes and traffic load
balancing. This will reduce power consumption.
G. Use Case7: Virtualisation of home
environment
NFV approach can be considered in home
environment. Currently CPE devices are provided in
house by service provider. These include residential
gateways, VOIP services and Setup box. NFV
technology facilitates virtualisation of all these home
devices to NFV cloud. It will make virtualised
replica of original device for example vRGW, vSTB
etc. This in return will reduce cost of equipment,
eliminate the work of maintaining CPE and improve
quality of experience.
H. Use Case8: Virtualization of CDNs
Delivery of the content especially video has
become a major challenge today. On another hand
requirement of improving quality of video is
required too. Content delivery networks are used to
manage the video services and to address traffic.
CDN is combination of CDN controller and cache
nodes. Usually CDN cache nodes are dedicated
physical appliances. This leads to disruption in
services at peak hours or wastage of some resources
during non-peak time hence reduction in resiliency
of CDN. Deploying CDN cache nodes as virtual
appliances on standardised appliances will overcome
most of the challenges like dynamic allocation of
resources, operational process of resources can be
harmonised and as appliances these software can be
replaced easily.
I. Use Case9: Fixed Access Network Functions
Virtualisation
Access network functions are the one that
add to network operational cost. These functions like
FTTcab/VDSL2 and and FTTdp/G which electronic
systems to be deployed in remote nodes located in
the street or in multiple-occupancy buildings. These
equipment must be efficient and consume less
power. However if access network functions are
virtualised the complexity can be reduced and low
power stand by modes can be used. Virtualization
can also support militancy, improve deployment
economies and reduce overall energy consumption.
VI. CURRENT WORK AND FUTURE
SCOPE
Over the past decades, the scale of
communications networks has been growing rapidly
with the emergence of more and more network based
services. However, network operators are
experiencing a decline in profitability. Responding
to such a challenge and paradox, the concept of
network function virtualization (NFV) has been
introduced with the aim of efficiently enabling
network based services by deploying standardized
and programmable hardware systems and by
virtualizing network functions with software.
A. Current Scenario of NFV
”Compared to the current approaches to
network and service deployment, which are based on
a large variety of propriety equipment, NFV opens
up many opportunities to the telecommunications
industry. By reducing the cost of equipment and
increasing the revenue with virtualized services,
NFV has the potential to revolutionize the entire
telecommunication industry” [18]. Despite the
potential of NFV, there are many challenging issues
to be addressed like how to design the network
equipment with programmability to efficiently
enable services; How to manage and orchestrate
NFV-based systems; what is the trade-off between
system performance and equipment cost?To
understand and solve these problems, there is
attempt for research and development on NFV, from
both academia and industry.
1) Research on NFV policies: In the paper ’High
Performance Evolved Packet Core Signaling and
Bearer Processing on General Purpose Processors’,
[19] the authors demonstrate the performance of an
NFV system using general purpose X86 processors.
In their study, they develop a prototype for the
evolved packet core (EPC), which is a key
component of Long Term Evolution (LTE) systems.
Experiment results show that, with a certain number
of processors, the NFV prototype can handle control
and data traffic from 50,000 subscribers, with
10Gbps downlink traffic and 4.8Gbps uplink traffic.
To enhance the performance of virtual network
functions (VNFs) in the NFV infrastructure (NFVI),
hardware acceleration (HWA) can be applied. In
Uniform Handling and Abstraction of NFV
Hardware Accelerators, [20]the authors investigate
this topic. Specifically, the authors explain the
background of HWA and the performance
requirements of NFV. Paper also elaborates on more
details of HWA for NFV, including some proof-of-
concept (PoC) demonstrations for both network

intensive acceleration and computing intensive
acceleration.
2) Policies for integrating SDN and NFV: NFV
and software-defined networks (SDN) are closely
related as well as emerging technologies, and hence
the integration of SDN and NFV is attracting
significant attention. An Open Service Chain as a
Service Platform towards the Integration of SDN
and NFV [21], the authors consider that service
chain policy is important to service providers, so
they propose a service platform for integration of
SDN and NFV. In this platform, the service chain
can be realized as a service; SDN is used to improve
the flexibility; NFV is applied to enhance the
adaptability; and encapsulating the service chain can
help guarantee scalability. Recently, with the
successful deployment and operation of the fourth-
generation (4G) cellular system, the fifth-generation
(5G) cellular system has become a hot topic. As a
result, researchers are interested in integrating NFV
into the design of 5G. In Integrating Network
Function Virtualization with SDR and SDN for
4G/5G Networks [22] the authors propose to
integrate NFV with SDN, as well as software-
defined radio (SDR), for 4G and 5G networks. The
authors explain the background of these
technologies, in particular existing standards. And
also elaborate necessary extensions facilitating the
integration and present open issues in this direction
[18].
B. Future of NFV
Overall it is believed that NFV will help to
reduce operational cost of networking. Its software
service capabilities will enhance customer
experience through content rich offering and reduced
cost [23].As result new customers can be brought
into network quickly. In this way NFV is creating
renewed interest in the networking business. NFV
will make the world more cloud-centric in future.
NFV will encourage the innovation in networking by
increasing transparency in network functions.
Presently, leading carriers like ETSI and ONF are
already working to achieve its realistic
accomplishment and mitigate challenges associated
with NFV. It is believed in future, Existing IP
networks will be more elastic, programmable and
dynamically managed on cloud platforms [24].
VII. CONCLUSION NFV
NFV had a huge surge in popularity
especially to telecom service providers as it provides
immediate gains in converting the network
appliances into virtual machines providing same
functionality as dedicated proprietary appliance
currently being used. Network function
virtualization can provide service providers with
significant gains in automation, thus saving costs,
computing power and electricity. SDN is a key
enabler for NFV. SDN and NFV are complimentary
approaches and both offer new way to design and
deploy the network with white box hardware.
Despite offering reduced capital expenditure and
operational costs, SDN and NFV together aim in
advancing software based networking approach
which offers agile and scalable networks. The
benefits of NFV for the consumers would include
latest telecom technology deployment, newer
services to subscribers. Furthermore, the use cases
document as released by ETSI [17] gives
comparatively a clear picture of the commercial and
the technical context that could benefit from
implementing NFV. Major telecom operators have
set up teams to study the aspects of incorporating
NFV. In the near future majority telecom service
operators and internet service providers will shift
their physical networks and infrastructure to virtual
state eventually benefitting businesses and
consumers.
REFERENCES
[1]. “Nfv-an
introduction,benefits,enablers,challenges and
call for action,” Introductory White Paper,
ETSI, 2012.
[2]. “Nfv-network operator perspectives on
industrial progress,” Update White Paper,
ETSI, 2013.
[3]. The ESTI website. [Online]. Available:
http://www.etsi.org/
[4]. What is nfv. [Online]. Available:
https://www.sdxcentral.com/resources/nfsv
[5]. Nfv. [Online]. Available: https://www.alcatel-
lucent.com/solutions/nfv
[6]. Nfv architectural framework. PDF. ETSI.
[Online]. Available: http://www.etsi.org
[7]. Nfv infrastructure overview. pdf. ETSI.
[Online]. Available:
http://www.etsi.org/deliver/etsi gs/NFV-
INF/001 099/001
[8]. Nfv infrastructure:compute domain. gs NFV-
INF003v010101p.pdf. ETSI. [Online].
Available: http://www.etsi.org/deliver/etsi
gs/NFVINF/ 001 099/003/01.01.01 60/gs
NFV-INF003v010101p.pdf
[9]. Nfv infrastructure:hypervisor domain. gs
NFV-INF004v010101p.pdf. ETSI. [Online].
gs/NFVINF/ 001 099/004/01.01.01 60/gs
[10]. ETSI. Nfv infrastructure:network domain. gs
NFV-INF005v010101p.pdf. [Online].
gs/NFVINF/ 001 099/005/01.01.01 60/gs

[11]. Service chain. [Online]. Available:
http://searchsdn.techtarget.com/tip/How-
SDN-and-NFV-simplifynetwork- service-
chain-provisioning
[12]. “Nfv management and orchestration:
Enabling rapid service innovation in the era of
virtualization,” NFV White Paper, Cisco.
[13]. ETSI. Nfv managment and orchestration.
http://www.etsi.org/deliver/etsi gs/NFVMAN/
001 099/001/01.01.01 60/gs nfv-
man001v010101p.pdf
[14]. SDX. Sdn versus nfv. [Online]. Available:
https://www.sdxcentral.com/articles/contribut
ed/nfv-and-sdn-whatsthe- difference/2013/03/
[15]. D. Metzler. Sdn and nfvdynamic duo of
next-gen networks. [Online]. Available:
http://www.networkcomputing.com/networki
ng/sdn-and-nfvdynamic- duo-of-next-gen-
networks/a/d-id/1319115
[16]. O. N. Foundation. Relationship of sdn and
nfv. onf2015.310 Architectural
comparison.08-2.pdf. [Online]. Available:
https://www.opennetworking.org/images/stori
es/downloads/sdnresources/ technical-
reports/onf2015.310 Architectural
comparison.08- 2.pdf
[17]. ETSI. Nfv: Use cases. nfv001v010101p.pdf.
http://www.etsi.org/deliver/etsi/
[18]. Department of Electrical and Computer
Engineering, University of Puerto Rico at
Mayaguez Liu, S. ; Feisullin, F. ; Ersue, M. ;
Cheng, Y., “Network function virtualization:
opportunities and challenges,” Network,IEEE,
pp. 4–5, 2015.
[19]. Hirschman, B.Mehta, P. ; Ramia, K.B. ;
Rajan, A.S. ; Dylag, E. ; Singh, A. ;
Mcdonald, M., “High-performance evolved
packet core signaling and bearer processing
on general-purpose processors,”
Network,IEEE, pp. 6–14, 2015.
[20]. Huawei Technol., Shenzhen, China Roch, E. ;
Jinwei Xia ; Molkho, A., “Uniform handling
and abstraction of nfv hardware accelerators,”
Network,IEEE, pp. 22–29, 2015.
[21]. Wanfu Ding City Univ. of Hong Kong, Hong
Kong, China Wen Qi , Jianping Wang , Biao
Chen, “Openscaas: an open service chain as a
service platform toward the integration of sdn
and nfv,” vol. 29, pp. 30–35, 2015.
[22]. Songlin Sun Beijing Univ. of Posts &
Telecommun., Beijing, China Kadoch, M. ;
Liang Gong ; Bo Rong, “Integrating network
function virtualization with sdr and sdn for
4g/5g networks,” Network,IEEE, vol. 29, pp.
54 – 59, 2015.
[23]. Sdn & nfv : The future for telecoms.
SDNandNFV.pdf . [Online]. Available:
http://www.nec.com/en/global/ad/insite/featur
e/pdf/SDNandNFV.pdf
[24]. Reshaping the future with nfv and sdn.
reshapingthefuture.pdf . [Online]. Available:
http://sdn.ieee.org/images/files/pdf/adl
belllabs 2015 reshapingthefuture.pdf

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