Page 314 - From Smart Grid to Internet of Energy

Internet of things for smart grid applications Chapter 7 279

management and application gateways [34]. The terminal and application ser-
vice modules interact with internal message interface that is fed by data center.
On the other hand, the customized service module interacts with data center and
it interfaces the enterprise customer and service integrator (SI) application sys-
tems. The third significant service type that is known as collaborative-aware
services is dedicated to analyze, and to generate decisions by using the inherited
data from information aggregation services.
This service requires node-to-node or node-to-user communication to per-
form required tasks which is appropriate for M2M and H2M communication
in smart grid applications. The fourth component of services infrastructure in
IoT are ubiquitous services that are omnipotence and omnipresence service
to provide communication requirements at any time and at anywhere.
Ubiquitous services utilize internet and cellular systems as communication
medium. International Telecommunication Union (ITU) defines the objective
of ubiquitous services to provide the seamless communication of anything in
the context of IoT. The networking should encompass the connectivity to
omnipotence and omnipresence capability, omnipresent reality to create a real
communication infrastructure, and intelligence to provide adequate communi-
cation to meet the increased requirements. Therefore, the high-level capabilities
expected from ubiquitous services are identified as open web-based services,
context-awareness, multi-networking capabilities, and end-to-end connectivity
in Y.NGN UbiNet recommendation. The communication devices operated in an
IoT environment require lightweight protocols in order to increase the interop-
erability and to prevent the high resource requirements. The software develop-
ing kits such as C, Java, Message Queue Telemetry Transport (MQTT), Phyton
or some script-based APIs are used to implement IoT-based smart grid appli-
cations [34, 50].

7.4.1 IoT protocols

There are two major IoT protocol classifications proposed in the literature
where one is based on data exchange protocols as bus-based and broker-based
while the other one lists the protocols into three sections as application proto-
cols, service discovery protocols, and infrastructure protocols [32]. The bus-
based protocol architecture enables clients to transmit a particular message
to the assigned recipients of that message. The protocols used for this objective,
which is also identified as service discovery protocol approach, include Data
Distribution Service (DDS), Representational State Transfer (REST) and
Extensible Messaging and Presence Protocol (XMPP). In the broker-based
architecture, broker that saves, transmits, filters, and ranks the priority level
controls the distribution of message. The prominent broker-based IoT protocols
are Advanced Message Queuing Protocol (AMQP), CoAP, MQTT and Java
Message Service API (JMS) protocols. Another classification method for these
protocols is to decide that if they are message-centric or data-centric. The