Fog Computing

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395 -0056
Volume: 04 Issue: 02 | Feb -2017 www.irjet.net p-ISSN: 2395-0072
© 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 1113
Fog Computing
Pooja More1,Juilee Kulkarni2
1 Dept. Of Computer Engineering,VESIT,University of Mumbai,Maharashtra,India
2Dept. Of Computer Engineering,VESIT,University of Mumbai,Maharashtra,India
---------------------------------------------------------------------***---------------------------------------------------------------------
Abstract -Fog Computingisatechnologythatextendscloud
computing and services to the edge of the network. Cloud
Computing is able to keep up with the current data processing
and conventional demand but it is unclearwhetherit willkeep
up to the demand put forth by the Internet of Things. Fog
Computing provides an architectural solutiontoaddresssome
of these problems. It provides data, computation, storage and
application services to the users like cloud. Fog Computing
enables a new breed of applications and services, and that
there is a fruitful interplay between the Cloud and the Fog,
particularly when it comesto datamanagementandanalytics.
Security issues in this area are also described with the
solutions. Fog Computing, thus makes itself an appropriate
application for a number of IoT applications and services.
Key Words: Fog, cloud, fog nodes, IoT, smart grid, smart
city, connected vehicle
1. INTRODUCTION
Cloud Computing is an emerging technology that is
revolutionizing IT infrastructures and flexibility. With cloud
computing, users are able to remotely store their data in the
cloud. It is an internet based model of computing where the
shared information, software and resources are provided
upon demand. This enables the users to access the cloud
computing resources anytime from any suitable platform
such as a cell phone, mobile computing platform, desktop
and laptops. It is the means of delivering any and all
technology – from computing power to computing
infrastructure, services and applicationstousersasa service
whenever and wherever they required it. Thus it can be
defined as a group of computers and servers connected
together over the Internet to form a network. Today, as
many enterprises and large organizations are beginning to
adopt the Internet of Things, the need for large amounts of
data to be accessed more quickly, and locally, is ever-
growing. This is where the concept of Fog Computing
comes to play. The metaphor fog comes from
meteorological term for a cloud closer to the ground. Indeed
in computer sciences the term fog explainstheextensionof
services provided by cloud to edge devices. In the
perspective of Cisco, fog is an extension of cloud. In this
paper we would explain in detail how fog computing is
emerging as an extension to cloud. [1-3]
2. LIMITATIONS OF CLOUD COMPUTING
Cloud offers services like platforms, storage and other
resources through the internet from a remote data centre.
Benefits like saving cost on physical resources, efficiency,
opportunities, innovations, flexibility are provided by it.
Although, cloud has several advantages to both users and
service providers, it has certain limitations too. Cloud
computing frees the end user and the enterprises from the
specification of many details. This bliss becomes a problem
for latency-sensitive applications,whichrequirenodesin the
vicinity to meet their delay requirements. Thus increasing
the round trip time. Also cloud has a requirement of high
speed reliable Internet connectivity, has limited bandwidth,
does not exercise any data protection mechanisms,platform
dependent and has limited control as well as flexibility. The
emerging trends in networking such as large distributed
Internet connected sensor networks, Internet of Things
(IoT), mobile data networks and also real time streaming
applications have characteristics that cannot be satisfied by
cloud computing. Thus fog computing is a collaboration of
Internet of Things and cloud computing.[4][5]
3. WHAT IS FOG COMPUTING?
The fog extends the cloud to be closer to the devices that
produce and act on IoT data. These devices can be situated
anywhere with a network connection whichcanbefactory,a
power pole, alongside a railway track, in a vehicle, or on an
oil rig. These are called as fog nodes. Any device with
computing, storage, and network connectivity can be a fog
node. Fog computing is a decentralized computing
infrastructure in whichcomputing resourcesandapplication
services are distributed in a logical and efficient place at any
point, along the path from the data source to the cloud. The
most important goal of fog computing is to improve
efficiency and reduce the amount of data that needs to be
transported to the cloud for processing,analysisandstorage.
Although this is mostly done to get efficiency, it can also be
done for security reasons.[6][7]

Figure 1: The fog extends the cloud closer to the devices
producing data
4. HOW FOG COMPUTING WORKS?
The data is originally generated at the edge devices and
sensors. Since these edge devices do not have the resources
required for storage and computation to perform analytics
and machine learning tasks so they send their data to the
cloud wherein the cloud servers are located too far away to
process and respond on timely basis. Sending all the raw
data to the cloud through internet may bringupimplications
of security, privacy. Here is where fog comes into picture.
Fog nodes perform functions like- to ingest data from IoT
devices, analyzing collected data,storethedata for1-2hours
and send periodic reports to the cloud.
 Most time-sensitive data isanalyzedonthefognode
which is closest to the edge device.
 Data that can wait for seconds or minutes can be
passed on to other aggregated nodes for analysis.
 Data which is least sensitive is sent to the cloud.
Thus the cloud would receive these reports from fog nodes,
analyze the IoT data from different sources, and also send
new application rules to respective fog nodes. Therefore,
fogging allows for short-term analytics at the edge, and the
cloud performs resource-intensive, longer-term
analytics.[6][7]
Figure 2: Fog architecture
5. ADVANTAGES OF FOG COMPUTING[4-7]
1) Conservation of bandwidth: Fog requires less
bandwidth as only selective and appropriatedata is
sent out on the cloud for processing and thus it is
cost effective.
2) Low latency: The data is analyzed where it is
generated; hence the round trip time is less leading
to low latency.
3) Real-time interactions: Important fog applications
involve real-time interactions rather than batch
processing.
4) Geo-distribution: In sharp contrast to the more
centralized cloud, the services and applications
targeted by the fog demand widely distributed
deployments. The fog, for instance, will play an
active role in delivering high quality streaming to
moving vehicles, through proxies and access points
positioned along highways and tracks.
5) Support for mobility: It is essential for many fog
applications to communicate directly with mobile
devices, and therefore support mobilitytechniques,
such as the LISP protocol 1, that decouple host
identity from location identity, and require a
distributed directory system.
6) Greater business agility: Developers can quickly
develop fog applications and deploy them where
needed. Machine manufacturers can offer MaaS to
their customers. Fog applications program the
machine to operate in the wayeachcustomerneeds.
7) Better security: Fog nodes can be protected using
the controls, physical security, cyber security
solutions we use to protect other parts of
environment. Also as the data is kept close to the
edge devices, in turn improves security.
8) Deeper insights, with privacy control: The data
needs to be analyzed locally and therefore no need
to send it to the cloud.
6. APPLICATIONS OF FOG COMPUTING
Data collected at extreme edges like vehicles, ships, factory
floors, roadways, railways, etc generate data across huge
geographical areas and so it becomes necessary to analyze
and act on the data in less than a second.
1) Connected Vehicle: The Connected Vehicle
deployment displays a rich scenario of connectivity
and interactions: cars to cars, cars to access points

(Wi-Fi, 3G, LTE, roadside units [RSUs], smart traffic
lights), and access points to access points.[5]
2) Smart traffic Lights: The smart traffic light node
interacts locally with a number of sensors, which
detect the presence of pedestrians and bikers, and
measures the distance and speed of approaching
vehicles. It also interactswithneighbouringlightsto
coordinate the green traffic wave. Based on this
information the smartlightsends warningsignalsto
approaching vehicles, and even modifies its own
cycle to prevent accidents.[5]
3) Smart Grid: Fog computing allow fast, machine to
machine (M2M) handshakes andhumantomachine
interactions (HMI) which would work in
cooperation with the cloud. Energy load balancing
applications may run onnetwork edgedevices,such
as smart meters and micro-grids. Based on energy
demand, availability and the lowest price, these
devices automatically switchtoalternativeenergies
like solar and wind. Fog collectors at the edge
process the data generated by grid sensors and
devices, and issue control commands to the
actuators. They also filter the data to be consumed
locally, and send the rest to the higher tiers for
visualization, real-time reports and transactional
analytics. Fog supports temporary storage at the
lowest tier to semi-permanent storage at the
highest tier. Global coverage is provided by the
Cloud with business intelligence analytics.[8]
Figure 3: Smart Grid
4) Smart City: Fog computing would be able to obtain
sensor data on all levels of activities of cities and
integrate all the mutually independent network
entities within. The applications of this scenarioare
facilitated by wireless sensors deployedtomeasure
temperature, humidity, or levels of various gases in
the building atmosphere. In this case, information
can be exchanged among all sensors in a floor, and
their readings can be combined to form reliable
measurements. Sensors will use distributed
decision making and activation at Fog devices to
react to data. The system components may then
work together to lower the temperatureinjectfresh
air or open windows. Air conditioners can remove
moisture from the air or increase the humidity.
Sensors can also trace and react to movements(e.g.,
by turning light on or off). Fog devices could be
assigned at each floor and could collaborate on
higher level of actuation. With Fog computing
applied in this scenario, smart buildings can
maintain their fabric, external and internal
environments to conserve energy, water and other
resources.[8]
5) Mobile Computing System: Fog computingorganize
highly virtualized computing and communication
facilities for mobile users. Fog computing provides
desirable localized services. With low-latency and
short-distance local connectionsFogcomputingcan
provide mobile users with the demanded services.
This significantly improves the service quality
provided to mobile users and, it save bandwidth
cost and energy consumptions. Fog computing
enable the linking of cloud based Internet and the
mobile computing.
7. SECURITY ISSUES IN FOG COMPUTING[9]
Fog computing involves various providers like: the fog
provider (entity which providesinfrastructuretotheusers.),
service provider (entity which uses the infrastructure to
deliver applications/services to the end users) and
consumers of the servicesprovided.Eachportionhasitsown
security measures andtheirown requirements.Thiscanlead
to loss of control over data, especially the providers and
consumers. As the providers are not aware of the contents
and security requirements of their infrastructure and the
consumers as they cannot control data of their own. The
security of stored data is the main issue as data isstoredona
third party; in turn the traditional security measure cannot
be implemented directly.Inthiscase,cryptographic methods
can be used.
As data centres prove to be a major component in fog
computing, data is managed between them in a cooperative
manner. The distributedprotocolsensuresecurity.Butwhen
attacks happen neither the attacker nor the file attacked is
identified.
Man-in -middle attack, a very traditional hostile attack has
higher probability of taking place. The gateways in the fog
area can be spoofed. It would be difficult for the fog nodes
and Iot devices to communicate using encryption and
decryption as it may utilizemorebatteryofmobiledevices.A
solution to this could be using Intrusion Detection
System.IDS can be used for analyzing and controlling access
as well as they generate log files for detecting malicious

behaviour. These systems can also detect Denial of Service
attacks and port scanning.
8. CONCLUSION
Although cloud computing is still preferred whenitcomesto
Iot applications, it is quickly becoming outdated. It would be
very soon that fog computing takes over and cloudispushed
to the side lines. The way the Internet of things is growing, it
needs a special infrastructure base that can handle all its
requirements, and fog computing seems to be the most
suitable option available. Fog computing accelerates
awareness and response to events by eliminating a round
trip to the cloud for analysis. It avoids the need for costly
bandwidth additions by offloading gigabytes of network
traffic from the core network. It also protects sensitive Iot
data by analyzing it inside company walls. Ultimately,
organizations that adopt fog computing gain deeper and
faster insights, leading to increased business agility, higher
service levels, and improved safety. Thus, Fog Computing
will play an important role in Iot applications to provide a
good user experience.
REFERENCES
[1]https://blog.oureducation.in/cloud-computing-an-
emerging-technology/
[2]http://internetofthingsagenda.techtarget.com/definition/
fog-computing-fogging
[3]https://www.youtube.com/watch?v=pdmyYbdLnkI
[4]http://www.academia.edu/8648486/Fog_Computing_Wil
l_it_be_the_Future_of_Cloud_Computing
[5]http://conferences.sigcomm.org/sigcomm/2012/paper/
mcc/p13.pdf
[6]https://www.cisco.com/c/dam/en_us/solutions/trends/i
ot/docs/computing-overview.pdf
[7] http://blogs.cisco.com/perspectives/iot-from-cloud-to-
fog-computing
[8]http://research.ijcaonline.org/ncrmc2015/number1/ncr
mc2898.pdf
[9]http://www.fict.ro/~ep/publications_files/ep_aop_ssfg1
6.pdf

Fog Computing

More Related Content

Fog Computing