Comparative Study for Secured Smart Grid Communications

COMPARATIVE STUDY FOR SECURED SMART GRID COMMUNICATIONS
Abstract:
One of the new forms of electricity network is said to be a smart grid that utilizes maximum
fidelity power-flow control, reliable and secured energy, and self-healing with the help of control
technology and digital communication. Depending on the infrastructure of intelligent and
secured network communication, we could able to upgrade the existing power grid into smart
grid system. For smart grid, it is necessary to have a security framework for the distributed
communication, sensing technologies and pervasive computing in grid networks. But the use of
certain technologies leads to certain vulnerable actions in the cyber security, which causes
untrustworthy system operations, unusual cost expenses and significant tragedy for the utilities
and consumers. In this paper we have discussed certain security issues in smart grid
communication with the comparative optimum solution.
Keywords: Smart grid, Cyber security.
Introduction:
A smart grid is said to be an integration of energy distribution system with the communication
system that forms a bidirectional information as well as power flow infrastructure. These
enhanced technologies not only advance the outdated communication but also transforms the
closed system into public data networks [1]. With the addition of novel services with the
distributed intelligence and state-of-the-art communication capacities, the smart grid
communications could be more efficient, flexible and inexpensive to afford and manage.
Although there are several benefits certain cyber and security threats should be considered by
every industry. The benefits of smart grids could be compensated with the vulnerabilities
produced by it. A significant innovative cyber attack vendor known as malware could
significantly decrease the demand of the smart grid thereby causing problem in the transmission,
generation and distribution progress [2]. A typical smart grid system is shown in the figure given
below.

Figure 1: Typical Smart grid communication system
From the figure 1, it could be seen that a horizontal integration of several regional centre is there
to control multiple substation and power plants. This smart grid communication is carried out in
layers, which collects the data and control the delivery of electricity. A regional station regularly
monitors the operation of the smart meters, power systems as well as the data acquisition system.
Remote Terminal Units (RTUs) with the circuit breakers, Human Machine Interfaces (HMIs),
Communication devices such as switches, hubs, and routers, log servers, data concentrators, and
a protocol gateway are certain units of the substation [3] [4]. To get on with the public network,
it is better to use the legacy cyber security techniques to give good result with the secured system
such as the internet. The operations carried out in the smart grid should do at a real-time with the
continuous operation. But commercial system does not necessarily satisfy these conditions.
Therefore, it is necessary to enhance the traditional system that works effectively for the cyber
security. Smart grid components could be composed of five major components:
 Process Control System (PCS) Security
 Smart Meter Security
 Power System State Estimation Security

 Smart Grid Communication Protocol Security
 Smart Grid Simulation for Security analysis.
Communication Network:
The communication Network is said to be the subpart of the smart grid that is composed of
Home Area Network (HAN) and Neighborhood Area Network (NAN). These networks provide
the data communication between the end user and the utility. AMI is said to be the key element
of HANs. HAN is composed of three main components:
1) WLAN: This is said to be the wireless LAN. This could be operated with the set of 802.11
standards. The smart devices provide the demand side management such as demand response and
energy efficiency management [5]. 802.11 provide the necessary security with the advanced
encryption standard (AEC). The integrity is offered by the AES-CBC-MAC algorithm. However,
802.11 faces certain security issues that could be easily hijacked, since by default they do not
provide any authorization mechanism. When the WLAN is easily hacked then the hacker could
change the entire smart grid data that does the falsified operation in the grid. IEEE 802.11
provides the easy pathway for the hackers to enter the WLAN network. If WLAN is hacked then
the entire connected network with the NAN could be completely targeted. Hence, we could say
that WLAN with its open standards and maximum throughput with the secured data is best suited
for HAN.
2) ZigBee: This works in IEEE 802.15.4 standard. Zigbee communication module handles
multiple devices at a minimum baud rate that explains the physical layer and Media Access
Control (MAC) standard. Here the threat occurs with the 802.15.4 protocol that is vulnerable to
jamming. This could affect the system’s availability to services. Another threat occurs in the
Zigbee while capturing the messages that are difficult to avoid in LR-WPANs [6]. The next case
with be exhaustion. In this case, the coordinator of the compromised node will temp the
maximum number of nodes that offers with the high quality link. At first, it will be forced to
work well followed by the battery depletion within short period of time.
ZigBee Smart Energy has been used by the large stakeholders recently. This technology works
with AMI that significantly goes well with the HAN network [7]. Two communication streams
will be supported by the ZigBee gateway that merges the utility AMI central database to the
smart devices. This gateway will therefore act as a firewall that will protect the network asset
from the grid side. It is necessary to configure and authenticate the ZigBee modules for the in-
house smart devices, in order to complete the network topology. However, security issues occur
when there is an opposition that occurs with the ZigBee coordinator node. This could sufficiently
deplete the battery causing the system failure. As a result it could be said that a low cost with the
minimum power consumption, usage of unlicensed spectrum with the existing smart energy
devices will provide effective communication for HAN.

3) Mobile Communication and Femtocells: Femtocells is the way to have a connection
between the household devices and the mobile operators with the help of optical fibers or
broadband connection along with the residential DSL [8] [9]. Femtocells could highly save the
power with the secure connection. It is said that the cellular femtocells with relatively higher
cost, secured implementation and limited device access will be best suited for HAN.
Challenges (LIMITATIONS):
Smart grid is said to be the coordination of various systems with the new and innovative
technologies in the system architecture that purely depends on various standards and regulations,
which is necessarily implemented in the communication protocols in order to support the
challenges faced by the commercial power systems [10]. The major challenge occurs while going
on with the inter-networking, efficiency and security services could occur that while dealing with
the smart communication networks.
Internetworking:
In certain application and devices, there is a lack of security and there is a cause of threats to
occur while going with several networks[11]. These types of networks are not preferred for the
smart grids. The cyber security network for the smart grid layers should be composed in such a
way that it has to deal with the maximum interruption, unnoticeable functionalities and
corruption. A way to deal with the intruders visit towards the network could be making the
transport network layer completely private i.e. the network could be completely owned by the
utility. This could stop the unwanted access of vulnerabilities over the internet. But this is not
possible in all cases. Therefore, there could be certain hostile groups who tend to cause cyber
attacks towards the power supply. A worm infestation is proved to have certain unusual impacts
to the environment. One of these cyber attacks is worm infestations which have proven to
negatively impact critical network infrastructures. For instance, if DoS has been attacked certain
vulnerable issues, then this could stop all the servers connected with the directory, which could
stop the users connecting to the networks. Hence the smart grid connection towards the internet
should be highly secured.
Private network has an advantage of having faster responses since the number of parties involved
is relatively low [12]. However, this is not the case when large amount of parties involved. This
could decrease the response and resolution.
Security Policy and Operations:
A proper connection should be maintained among the components of the smart grid
connection in order to enhance the reliability [13]. A hacker could attempt to gain access
over the component and change the configuration that could interrupt all other system
connected to it. This is extensively done in DoS since hacking the server could interrupt all
other nodes connected to it [14]. During the protocol development it is necessary for the
protocol designers to pay attention to this threat.