Page 307 - From Smart Grid to Internet of Energy

Internet of things for smart grid applications Chapter 7 273

infrastructure. Besides the encryption, application layer accommodates secure
communication protocols (HTTPS), application protocols (CoAP), access pro-
tocols (Simple Object Access Protocol-SOAP, Lightweight Directory Access
Protocol-LDAP), and secure network protocols (Distributed Network
Protocol-DNP3, Secure Shell-SSH). The communication infrastructures of con-
ventional grid are based on legacy methods and equipment. However, the fea-
tured communication technologies of IoT technologies are addressed according
to the development of infrastructures, services and protocols, security, privacy,
interoperability, energy efficiency, and sensor networks.

7.3.1 Software-defined networks (SDNs)

SDN provides several advances to enhance flexibility, reliability, scalability,
and interoperability of IoT-based smart grid communication infrastructure as
an encouraging model. It allows to dispatch control and data communication
devices into different planes. Principally, SDN offers an open architecture
model in three stages by separating control and data planes, enabling centralized
logical control and incorporating network programming capability. Thus, SDN
copes with communication problems occurred in conventional architecture
combining protection control, billing, and monitoring data transmission. The
open architecture of SDN prevents inefficiency of M2M communication, and
provides facilitated design, deployment, management, and maintenance of
communication networks. This recent networking architecture has been sepa-
rated into three layers as application, control, and physical layers. The applica-
tion layer performs system operations and managements as the highest layer,
and control layer interfaces application layer with physical layer. The APIs per-
forms communication between application and control layers. Thus, control
layer becomes a network operating system due to APIs and manages physical
layer regarding to instructions. SDN enables operators to improve network
function virtualization (NFV) applications that provides aggregation of several
DERs and microgrids that are using different communication technologies on a
virtual network. The integration of SDN and smart grid provides several ben-
efits for improving communication networking, real-time monitoring applica-
tions, increased latency management, and bandwidth control [40, 41].
In addition to benefits of SDN supplied to communication infrastructure, it
also improves resiliency of power network against cyber-attacks. SDN enables
communication system for intrusion detection, isolating selected devices upon
detection and protection approach, decreasing malicious traffic and denial of
service attacks, and remote control of sensors and smart meters.

7.3.2 IEEE 802.x based communication technologies

Almost all IoT communication methods that are presented in the following are
based on RF wireless transmissions. The communication infrastructure is in the