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178 From smart grid to internet of energy

ISO/IEC 14443 standards for Type A. ISO/IEC 21481 standard defines commu-
nication mode selection mechanism for devices maintaining ISO/IEC 18092,
ISO/IEC 14443 or ISO/IEC 15693. Current and predicted applications of the
NFC technology cover contactless payment processes, identification, access
control, and automation. Fast development of smart devices also provides novel
services for the NFC technology.

5.3 Communication technologies for low-rate WPANS
5.3.1 IEEE 802.15.4 standard
In 2003, IEEE 802.15.4 standard has been introduced to meet demands for com-
munication technologies that are able to provide low-power consumption fea-
ture. The IEEE 802.15.4 working group (WG) developed this standard as the
first standard for low-rate WPANs (LR-WPANs). The main purpose of the
802.15.4 is to put forward a new infrastructure for wireless network applications
that has several critical characteristics such as low complexity, energy saving
mode and low cost [16]. The standard defines both PHY and MAC layers as
the base layers of the protocol. The fundamental signal processing transactions
such as modulation, channel selection, energy management and data transmis-
sion are performed in the PHY layer whereas frame management and collision
prevention processes are realized in the MAC layer. The upper layers of the pro-
tocol stack are specially defined by the technologies such as ZigBee, Wireless
Highway Addressable Remote Transducer (WirelessHART) and IPv6 over Low
power Wireless Personal Area Networks (6LoWPAN).
In the IEEE 802.15.4 standard, there exist different network node possibil-
ities that may be full-function device (FFD) or reduced-function device (RFD).
The first one contains nodes that can entirely ensure the standard due to the fact
that the nodes can cover all features of the network. Hence, the FFDs in any
network scheme may act as an end-device, a local coordinator, or a personal
area network (PAN) coordinator. It is worth noting that at least one FFD should
be employed in an 802.15.4 network. The RFD node type only acts an end-
device and forms basic nodes that have some capabilities of the network due
to memory and processing scarcities. Since the RFDs behave as end-devices
in the network, they cannot transmit messages to their ultimate targets. In addi-
tion, a local coordinator, which should be associated with a PAN coordinator or
a previously related local coordinator, provides synchronization owing to bea-
con transmissions.
As can be seen from Fig. 5.2, the IEEE 802.15.4 standard can support several
node topology schemes called star, mesh (P2P) and cluster-tree. In a star topol-
ogy, all devices can communicate with a PAN coordinator by using master/slave
network model. One of the FFDs can take over the coordinator role of the net-
work, and the remain nodes (other FFDs and RFDs) can only convey with the
network coordinator. The nodes may create more complicated network scheme