On the Communication Requirements for the Smart Grid

doi:10.4236/epe.2011.31008

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Energy and Power En gi neering, 2011, 3, 53-60

doi:10.4236/epe.2011.31008 Published Online February 2011 (http://www.SciRP.org/journal/epe)

On the Communication Requirements for the Smart Grid

Mohamed Daoud, Xavier Fernando

Electrical and Computer Engineering Department Ryerson University, Toronto, Canada

E-mail: [email protected]

Received November 5, 2010; revised December 15, 2010; accepted January 7, 2011

Abstract

The current power grid is facing many challenges that it was not designed or engineered to handle which

range from congestions and major blackouts to the overwhelming increase in demand and security concerns.

The current electric grid was established before the 1960’s. It is believed that the electric grid is the most

complex and gigantic machine ever made in human history; it consists of wires, cables, towers, transformers

and circuit breakers installed together in outdated manner. During the 60’s, computers and sensors were used

to monitor and slightly control the grid; however, fifty years later these sensors are considered less than ideal .

Presented here is a review of the smart grid communication network in terms of configuration, bandwidth

and latency requirements as well as the technology used. We simulate the access layer of the smart grid net-

work and show that no single available communication technology can be used for all layers of the smart

grid; thus, different technologies for different layers are needed. A new protocol for optimizing the smart

grid is recommended.

Keywords: Smart Grid, Core Network, Distribution Network, Access Network, Energy, Latency, Bandwidth

1. Introduction

Climate change and global warming have been among

the major concerns of human beings over the last few

years. Recently huge efforts have gone into integrating

renewable and green sources of energy with the grid and

making the grid smarter; that is, to increase its energy

efficiency, storage and moderate energy consumption.

To that extent reducing and shifting peak load are es-

sential to support renewable energy generation and

would lead to shutting down the extra, carbon-intensive

power plants that are used only during peak hours.

Therefore, governments along with utilities hav e put into

effect mechanisms to reduce peak demand, including

time-of-use pricing, installation of load management

devices, load shifting and peak eliminating technologies.

The Smart grid designed for the future electricity sys-

tem encompasses many of these solutions and technolo-

gies. It empowers energy consumers as well as utilities to

gain better control over energy consumption.

However, it seems that these are all impossible with-

out considering the key role of communication technol-

ogy. In fact, various communication technologies have

the potential to revolutionize today’s grid and expedite

renewable energy projects.

If we look at the electric grid in the United States we

will see that it consists of 3,100 electric utilities operat-

ing more about 10,000 power plants and 131 million

customers consuming more than 3,500 billion kwh every

day [1,2]. Between them there are 157,000 miles of high

voltage electric transmission lines [1]. The average age

of the power grid transmission lines is 50-60 years [3]. In

the decade from 1988 to 1998, the electricity demand in

the U.S grew by 30%, yet only 15% of new transmission

capacity was added [4]. This is a giant machine that

needs to be operated efficiently to save both resources

and the environment. But due to its age, being somehow

deregulated and inefficient it is very hard to solve this

optimi zation problem.

The current system is inefficient because when a fault

occurs the utility does not know unless the customers call

in. Also because of the congestion and many blackouts

that take place regularly, such as the one in the summer

of 2003 in the Northeastern US and in Canada. Power

outages and power quality issues cost U.S businesses

more than $ 100 billion on average each year [3]. Power

inefficiency has a negative im pact on the environment as

well. To be more specific, roughly 40 percent of Amer-

ica’s total CO2 emissions come from the production of

electricity used in homes, offices, and factories [5]. To

M. DAOUD ET AL.

add intelligence to an electrical power transmission sys-

tem, we need to have independent processors in each

component and at each substation and power plant.

These processors must have a robust operating system

and be able to act as agents that can communicate and

cooperate with each other to compose a large distributed

computing pl atform [6].

No one clear definition for the Smart Grid can be

found, but it can be described as Advanced Metering

Infrastructure (AMI) accompanied by substation and

distribution automation services and enhanced distribu-

tion and outage management. This shows the wide range

of requirements and expectations from the Smart Grid.

The Electric Power Research Institute (EPRI) defines the

Smart Grid as, “A power system that serves millions of

customers and has an intelligent communications infra-

structure enabling timely, secure and adaptable informa-

tion flow needed to provide power to an evolving digital

economy” [7]. Smart Grid will offer a system-wide “ma-

cro” view in aid of conserving electrical energy within

the grid and related distribution systems [8], by control-

ling some home appliances such as the thermostat of the

air conditioners, charging the Plug in Hybrid Electrical

Vehicle (PHEV), and switching the washing machines,

dryers, and dishwashers to low demand times when the

hydro is less expensive. These appliances will be smart

and equipped with a special chip; the smart appliances

could talk to the grid and decide how to operate best and

automatically schedule their activities at strategic times

based on available generation [9]. The smart meter will

play an important role here; also the existence of a robust

reliable communication network is essential.

Smart Grid can be described as an energy network, a

network just like the internet. Rather than downloading

and uploading data, customers will download and up load

electricity [10]. Rather than having a modem indicating

how many megabytes of data downloaded or uploaded,

customers will have smart meters showing the kilowatts

they used or generated and the price according to the

time of use. Smart Grid is information technology infra-

structure meeting electrical infrastructure to satisfy fu-

ture energy needs; it will combine the maturity of the

electric grid with the efficiency, connectivity, and cost

gains brought about by information technology [11].

IEEE recently took the initiative to define the standards

and guidelines for the Smart Grid; IEEE P2030 was

formed for that purpose [2].

According to the United States Department of En-

ergy’s Modern Grid Initiative report, a modern smart

grid must:

1) Be able to heal itself

2) Motivate consumers to actively participate in op-

erations of the grid

3) Resist attack

4) Provide higher quality power that will save money

wasted from outages

5) Accommodate all generation and storage options

6) Enable electricity markets to flourish

7) Run more efficiently

8) Enable higher penetration of intermittent power

generation sources

This paper presents a complete review of the commu-

nications requirements for the smart grid and the work

done so far.

The rest of the paper is organized as follows: Section 2

presents the hierarchy of the communications system and

also discusses latency, b andwidth, an d Quality of Service

(QoS). Section 3 is a description for all three layers of

the network. Section 4 presents some of the work already

done. Finally Section 5 concludes our review and gives a

glimpse of some future work.

2. Communications for Smart Grid

Integrated, high performance, highly reliable, scalable,

ubiquitous, and secure-these are the characteristics de-

scribing the smart grid communication network. The

communication network will be responsible for gathering

and routing data, monitoring all nodes and acting upon

the data received.

Apparently the amount of data transferred daily will

be huge and very sensitive, so the communication net-

work must be secured against external attacks. Smart

grid communication network will depend on both wire-

less and wired communication technologies; however,

one of the main challenges of the smart grid communica-

tion network is that wireless technologies are totally

turning over every 4-6 years and utilities are building

systems for 15-20 years. This is why unifying and con-

verging networks around IP is so critical. Hence arises

the idea of communication networks not being tied to a

specific carrier technology. Another challenge is the se-

curity; keeping all this information secured and prevent-

ing hackers from getting in to the grid is truly a matter of

national security.

In [10], S. Keshav and C. Rosenberg compared the

smart grid communication n etwork to the internet, which

is the largest and most important communication net-

work on earth. One of the main differences is the avail-

ability; the internet is not available at every house, but

the smart grid should be available to every house with

high reliability. The smart grid communication network

will be like the intern et in the sense of be ing a delay tol-

erant network, providing congestion control, and operat-

ing in distributed control manner.

M. DAOUD ET AL.55

2.1. The Communications Network Hierarchy

Smart Grid communication network will be a ne twork of

networks that may use different communications tech-

nology or just one, allowing two-way, reliable, and se-

cure communications.

It will be formed of millions of smart meters at cus-

tomer premises connected to a few thousand substations,

which in turn will be connected to fewer control centers

and power plants. The network will be huge; thus, it is

recommended to take the form of clusters according to

geographical locations. Each cluster will have a limited

number of smart meters ranging from a few hundred to a

few thousand connected to a few substations and control

centers. A cluster may or may not have a power plant as

power plants will be shared between more than one clus-

ter.

There will be three different layers in the communica-

tions network, as described in [12].

Core network handles connectivity between substa-

tions and utilities’ head offices i.e. control centers.

Distribution network as shown in Figure 1, handles

broadband connectivity fo r transmitting data co llected by

the smart meters sensors and concentrators located on the

grid to their related databases and analytics servers,

which are located at headquarters.

Access network handles last-mile connectivity at

homes, offices, and municipal facilities to the smart me-

ters.

Millions of messages every second will be going back

and forth in the network; different messages for different

reasons can be sorted into three main categories [13,14].

 Real-Time Operational communication require-

ments

 Administrative Operational communication requi-

rements

 Administrative communication requirements

Real-Time Operational communication is the commu-

nication in real time required to maintain operation of the

power system [13]; it is the control and protection for

Figure 1. Smart grid distribution network.

messages. It requires low latency and has a highly suc-

cessful delivery rate.

Administrative Operational communications require-

ments are usually those messages that describe major and

minor system disturbances like local event recorders,

disturbance recorders, and power swing recorders. These

do not need to take place in real time. This type of in-

formation is needed to predict future demand.

Administrative communication requirements include

the voice communications between different locations

for administrative purposes. This type of communication

can be carried over cellular or land line networks; it does

not necessarily need to be part of the smart grid commu-

nications network.

These different categories point out one of the main

requirements for the smart grid communication network

which is supporting QoS in order to prioritize traffic on

the network.

2.2. Requirements for Smart Grid

Communication Network

Latency is the delay in the network or the expression of

how much time it takes for a packet of data to travel from

one point on the network to another. There is a need for a

communication infrastructure with exceptionally tight

latency characteristics as it is one of the most stringent

requirements for the grid. If the control center misses any

input, then it might substitute the missing input with in-

puts from other sensors which can produce different ac-

tions that co ul d l ead to erroneous resul t s [ 1 5] . K . M oslehi

et al. [16] discussed latency within the smart grid com-

munications network. They explained that the network

will have different latency times; the grid is huge so if the

data sent is for the purpose of system wide coordinated

controls it should have higher laten cy (slower cycle) than

if the data is required for local analytical needs or re-

sponding to rapid events (faster cycle).

Bandwidth: it is extremely important to determine th e

bandwidth requirements for the smart grid communica-

tion network because it is a direct factor when choosing

the transmission media (e.g. fiber optics, radio waves,

coaxial cables, etc.) as well as choosing the communica-

tions technology (e.g. 3G, LTE, WiMAX etc.). IEEE

P2030 standard is still trying to define the bandwidth

requiremen ts [17]. An im portant point he re is that because

of the extremely large number of endpoints, the commu-

nications system bandwidth requirements can quickly

become untenable if appropriate precautions are not tak-

en.

QoS: Not all messages have the same importance nor

should they be delivered within the specific latent pe-

riod.”)

M. DAOUD ET AL.

3. Layers of the Network

3.1. Core Network

In [18,19], K. Moslehi et al. gave an example of a Dis-

tributed Autonomous Real Time (DART) smart grid

network consisting of 10 regions, each region having 20

control centers; each control center is connected to 500

substations, according to the geographical areas. Each 10

substations can be grouped into a zone.

According to the DART system in [18,19 ], the latency

calculated in the control area between the 500 substations

and their control center is 240.8 msec. This value meas-

ures latency in the system but does not indicate the

maximum tolerable latency.

In [15], V. k. Sood et al. discussed the latency within

smart grids and concluded that faults require continuous

high rate monitoring by the control centers. For rapid

detection of such faults th e latency shou ld be in the order

of tens of mi lliseconds , with 100 msec being the accepte d

fault detection time in medium sized systems.

For bandwidth calculation purposes, a snapshot taken

at the control area in the DAR T system [18,19] shows that

the required transfer rate is 5.089 MB/sec. This number

may seem large due to the extensive DART s ystem where

500 substations are connected to one control center, but a

smaller system as in [15] with three voltages and three

currents to be sampled and sent to a control centre have

only a 2-5 Mbits/s ba ndwidth requirement. This data rate

is indicative of an application with a relatively low to

medium data rate production.

Fiber optics can be used for communication in the core

network. They were recommended in [15] because of

their very low latency of under 5 µsec latency per kilo-

meter length of strand. But fiber is not available to all grid

operators, and not all points in the system can have fiber

cables extended to them. In [20] the author agrees wi th the

above argument and suggests optical fiber because of its

low latency; however, the problem again seems to be

deploying the fiber optics all over the network and to the

customer premises. The author highlighted the idea that

different technologies can be used for different parts of

the network as long as they can talk to each other i.e.

based on IP. Since the core network is the part that han-

dles connectivity between substations and utilities’ head

offices/ control centers, so installing fiber optics will not

be as difficult because the num ber of substations and head

offices is relatively small and usually built in specific

locations carefully chosen b y the utility company.

3.2. Distribution Network

The following calculations done in [18,19] for the DART

system measure the latency within the substation: be-

tween smart meters and a specific substation is 2.2 msec

and in the zone between substations i s 4.8 msec, but this is

not the maximum tolerable latency.

The maximum tolerable latency is higher; the latency is

in the order of a few milliseconds, around 10 msec [2]

while in [18] it was assumed to be 12 msec; i.e. 6 msec

one-way delay. These latency requirements change sig-

nificantly in case of islanding. Islanding is the condition

where the power grid is broken into independent asyn-

chronous sections, each having its own generators and

loads. According to the IEEE standard 1547-2003 the

Distributed Resource (DR) must detect the unintentional

islands and cease to energize them within 2 seconds of the

formation of the island [15]. Unintentional islanding may

lead to abnormal voltage and frequency change out of the

acceptable range. In [15] the latency in case of islanding

was estimated to be maximum 6 cycles or 100 msec.

Pramode Verma et al. [2] proposed a method to calcu-

late the bandwidth in distribution network by assuming a

system of one transmission substation connected to one

distribution substation and control center connected to

10,000 feeders. Each feeder is connected to 10 smart

meters, making a total of 100,000 smart meters each

sending one message per second in addition to the control

messages. Thus, in the case of busy hour the syste m may

have one million messages per second. Assuming each

message is 100 bits, the latency requirement is 10 msec

and the messages follow a Poisson discipline at each node,

bandwidth is calculated to be 100.01 Mbps. Changing the

delay requirement to 10 msec for 99% of the messages

causes the bandwidth to increase to 100.056 Mbps. Re-

peating the same calculations for a 400 bit message, the

bandwidth was found to be 400.04 Mbps, but if the delay

is limited to 10 msec for 99% of the messages the band-

width increases to 400.086 Mbps. It was concluded that

both of these situations result in very poor bandwidth

utilization, while a higher level of utilization will not

meet the assumed latency constraint [2].

Utilizing the bandwidth is an important issue that

needs to be carefully studied; Carl H. Hauser et al. [21]

proved that a T1 line carrying a 400 bit message with

latency constrain t of 10 msec results in utilizing 6% only

of the T1 line.

In [16,18], the required transfer rate was found to be

3.31 MB/sec in the substation and 8.1 MB/sec within a

zone formed of 10 geographically grouped substations In

Distributed Autonomous Real Time (DART) system

which they proposed, the maximum data transfer rate

required is 8.1 MB/sec. According to the analysis, the

size of data for a snapshot describing the instantaneous

status can vary between 2.5 kBytes for a substation to

250 Mbytes for the entire grid [18]. This type of infor-

M. DAOUD ET AL.57

mation is ve ry usef ul fo r det e r mining the bandwidth.

As a communication technology for the distribution

network, WiMAX seems to be a very good candidate as

it has the benefits of fiber, such as low latency and large

bandwidth. At the same time it can be easily deployed as

it needs no line of sight and no expensive physical infra-

structure as fibers do. Other ben efits of WiMAX include

the following: it provides higher speed than 3G, it is an

emerging broadband wireless access technology and it

can provide high-speed connection to internet, with data

transmission less than 50 km [22]. One of the most im-

portant advantages of WiMAX, besides the high trans-

mission rate is the QoS guarantees, also the adaptive

modulation and closed loop power control are very at-

tractive options. In the Smart Grid some messages may

be more important than others — the control messages

should have higher priority than billing messages for

example [22]. WiMAX is an attractive solution to be

used in the communication network since WiMAX pro-

vides longer distance communications (10-30 miles) with

a data transfer rate of 75 Mbps while commun icating out

of sight. This system also communicates point to point

with different vendors, and the authors added that it may

be used as the spine of transmission and distribution

communications system [23]. In [15], the authors ex-

pressed their interest in wireless technologies, especially

4G like WiMAX and LTE as both can provide low la-

tency and high bandwidth. Moreover the QoS, ensures

that traffic can be prioritized on the network also they are

built on IP. In [15], it was mentioned that wireless tech-

nology 4G especially WiMAX can be used for transfer-

ring data from smart meters from homes to transformer

stations and contro l centers as it will give h igh sp eed and

low latency. Latency in a WiMAX link from the base

station to CPE (customer premises equipment) is typi-

cally equal to or less than 10 ms [15].

WiMAX will easily satisfy the bandwidth require-

ments of the distribution network as it offers large band-

width ranges between 5MHz to 20 MHz.

3.3. Access Network

The smart meter will not only show the customer’s usage

and generation, but will also collect in formation fro m the

smart appliances at home through an access network

indicating the customer’s behavior and informing the

grid of any increase or decrease in demand.

The amount of data will depend on the number of

smart appliances in the home; the more smart appliances,

the more bandwidth needed. Figure 2 shows a smart

meter collecting data from smart appliances through the

access network and sending this data to the substation

through the distribution network. Not all appliances will

Figure 2. Smart meter collecting data from the access net-

work inside a house and passing it to the distribution net-

work.

be sending/receiving data at the same time. They will

send/receive at scheduled times or when needed. It will

be easy to design and manage the access network be-

cause of its small size and the limited amount of data to

be transferred.

In [20] an in home network was mentioned where the

smart appliances can communicate to the smart meter

with a data rate of 20 Kbps while the maximum data rate

is 128 Kbps.

Such network can use any short range communication

technology like ZigBee or bluetooth. In fact ZigBee is

preferred because it is an open standard protocol based

on IEEE802.15.4 which is a high level communication

protocol using small low power digital devices designed

for low cost and low power communications. Because

ZigBee can activate (go from sleep to active mode) in 15

msec or less, the latency can be very low. Because Zig-

Bees can sleep most of the time, average power con-

sumption can be very low, resulting in long battery life.

Zigbees have a small range and limited bandwidth and

the data rate isn’t very high compared to fiber as an ex-

ample, so they are more suitable for indoor applications

like home automation. This technology is even preferred

over Bluetooth in the short range applications because it

consumes far less power. The obvious result is an in-

crease in the life expectancy of the network [24].

Zigbee radio nodes are self organizing and self healing

when forming mesh networks. Given the fact that IEEE

802.15.4 radios can successfully transmit packets a dis-

tance of 50 meters — nearly half the length of a football

field-the meters can form either a mesh or star network

with other meters in the neighborhood [24]; 50 meters is

sufficient to allow communication between smart appli-

ances and the smart meter at home. Zigbee is both power

and cost efficient.

We did a simulation for an access network where we

assumed a typical mid-house size with 11 smart devices

communicating through a Zigbee network to the smart

M. DAOUD ET AL.

meter. We assumed Poisson distribution for packets gen-

eration at the smart devices with a constant packet size of

1 Kbyte. Packets are sent to the smart meter as soon as

they are generated at the smart devices. We simulated 24

hours of traf fic on the access network and found th at the

end-to-end delay in the network ranged between 35 msec

and 80 msec, with a spike of 0.1 sec during the peak h our

of the day. Our results are shown in Figure 3. We calcu-

lated the average Bit Erro r Rate (BER) at the smart meter

and we got BER = 0.06 = 6%. In Figure 4 we plotted the

data throughput over the day; it ranged from 90 Kbps to

100 Kbps which shows that the minimum required

bandwidth should be a little bit over 100 Kbps.

A Smart grid communication network will consist of

different layers each using a different technology; thus,

all these technologies should be able to communicate

together using the same protocol. For best performance,

Figure 3. Average end-to-end delay in the access network.

Figure 4. Bandwidth of the access network.

all layers shoul d be IP net w orks.

IP networks are widely used because of their open

standard, simplicity, reliability, security, and robustness.

The world is going to the all-IP networks concept. IP is

being used in internet, computer networks, cellular net-

works, Wi-Fi, 3G, LTE (Long Term Evolution) and al-

most all new technologies where it provides a low cost

and efficient solution. On the other hand, there is Asyn-

chronous Transfer Mode (ATM), which is a packet-

switching technology that delivers data packets over vir-

tual circuits or preserv ed paths through the network [25].

ATM is more expensive than IP, but it provides guaran-

teed latency and drop rates. ATM is used as the back-

bone of IP networks to implement point to point links.

IP seems to be a more attractive solution for smart grid

networks than ATM in terms of the ability to interact

with other communication networks and the internet. It is

also in an economical method, as the cost of deployment

and maintenance can be reduced significantly with the

use of IP-based technol o gi es [2 ,2 0] .

When talking about IP it is necessary to mention the

layers on top of it. IP is usually backed with Transmis-

sion Control Protocol (TCP) to provide a higher delivery

rate and retransmission in case of lost data [15,21,22,25].

TCP is well known for having the highest level of packet

delivery assurance, but this comes at a price of higher

latency duty to the larg e overhead [15,21]. But it can still

be used in combination with prioritization through QoS

and used for highly important applications that need as-

sured delivery. User Datagram Protocol (UDP) is another

layer that comes on top of IP, but in contrast to TCP,

UDP is lightweight with smaller overhead and latency

than TCP but at the cost of non assured data delivery

because receipts are not acknowledged. A practical ap-

plication of UDP is the multimedia features over the in-

ternet, where the loss of some packets can be tolerated.

By analogy the same concept can be used for smart grid

communication network; TCP could be used for mes-

sages that require high delivery rate like control mes-

sages while UDP can be used for sending data where the

loss of some packets will not affect the overall perform-

ance of the system.

Currently most IP network are based on IPv4, bu t IPv6

protocol can be used; it has an address code set at 128 bit,

which means that there are 2128 IP addresses available.

IPv6 is supposed to be faster than internet IPv4, and it

will maintain dialogue with any object such as household

appliances, sensors and so on [22]. Although the IPv4

extensions allow multicast traffic and certain QoS, IPv6

is still preferred as it inclu des the following services and

new features: more addresses, mobility, security, etc [20].

It is recommended having the Smart Grid communica-

tion network as a separate entity from the internet as in

[2,21] where it was concluded that the public internet

M. DAOUD ET AL.59

will lack admission control and guaranteed latency de-

livery and will never be able to supply private data net-

work for the power grid infrastructure needs. The lack of

security of the internet is another major concern.

4. Current Projects

Many research projects and activities have been done in

the area of smart grids, and some of them are listed in

this section.

GAD project in Spain is targeting residential con-

sumption. They developed a Domestic Power Manager

(DPM) which is much like the smart meter, and took

many steps in defining a communication network using

open standard protocols to support active demand side

management [20,24].

GridStat is being developed by Washington State

University. They are offering a flexible approach to pro-

viding communication support for electric power grid

operations. It is based on a publish-subscribe (pub-sub)

model, where the substations periodically publish status

while the control centers and other substations subscribe

to a selected set of statuses [21,25].

DisPower, CRISP, MicroGrid and Fenix are differ-

ent projects adopting the concept of an internet-like net-

work in the sense that decision making is distributed all

over the network since the control nodes are spread

across the system [26].

Modern grid strategy [27] is a project by the U.S

department of Energy (DOE) that started in 2005 through

the National Energy Technology Laboratory (NETL).

They are developing smart grid concepts and sharing it

with key stock holders. Their mission is to accelerate

grid modernization in the United States. They support the

idea of using different communication technologies in

different layers of the smart grid.

IntelliGrid is an initiative by EPRI to create the tech-

nical foundation for a smart power grid that links elec-

tricity with communications and computer control to

achieve tremendous gains in reliability, capacity, and

customer services. A major early product is the Intelli-

Grid Architecture, an open-standard, requirements-based

approach for integrating data networks and equipment

that enables interoperability between products and sys-

tems. This program provides utilities with the methodol-

ogy, tools, and recommendations for standards and

technologies when implementing systems such as ad-

vanced metering, distribution automation, demand re-

sponse, and wide-area measurement [28].

5. Conclusion

This paper presented a review of communications for

smart grids in which the specific needs of the smart grid

communication system were discussed. The hierarchy of

the system, nature of the network, latency, bandwidth

and proposed communication technologies to be used

were all surveyed. Current active projects were men-

tioned as well. It was found that the latency within the

distribution network should be kept at 10 msec, and the

required transfer rate in case of a zone containing 10

substations should be 8.1 MB/sec. Our simulation results

for the access layer in a smart grid network point out the

access layer requirements in terms of end-to-end delay,

and bandwidth. Also it was concluded that no single

communication technology will be able to satisfy the

requirements for the whole network; rather different

technologies shou ld be used for different parts.

There is still much work to be done in the smart grid

area, especially in the communications part. Since all of

the available communication techniques are off the shelf

technologies designed for different reasons, none of them

addresses the smart grid needs. Most of these technolo-

gies support mobility, handover, an d many other features

which are not needed for the smart grid due to its nature;

thus, a communication protocol should be developed and

optimized specially for the smart grids th at cover end-to-

end networks. This special protocol should be able to

automatically set the QoS configurations when applica-

tion requirements change based on th e grid events, and it

should translate the self-healing grid capability to self-

healing communication network.

6. References

[1] L. H. Tsoukalas and R. Gao, “From Smart Grids to an

Energy Internet: Assumptions, Architectures and Re-

quirements,” Third International Conference on Electric

Utility Deregulation and Restructuring and Power Tech-

nologies (DRPT 2008), Nanjuing, 6-9 April 2008, pp.

94-98. doi:10.1109/DRPT.2008.4523385

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