IEEE Power & Energy Magazine - May/June 2014 - 39

serving the end users so as to exploit the advantages conferred by the other two entities.
one of the important merits of this three-entity framework is that it clearly captures the major differences between
the communication systems used in traditional electricity
grids and in smart grids. In particular, if we were to use this
framework to represent the communication system typically
used by traditional electricity grids, only the operation and
business networks would be necessary.

Communications Within
and Between Entities
In this section, we describe the internal structures of each
entity in our proposed framework. We discuss the communication issues within each entity and between entities.

Communications in the Operation Network
as shown in Figure 3, the operation network consists of
seven major components: the business network gateway
(Bng), consumer network gateway (cng), control centers
(ccs), generation station (gS), substation (SS), transmission
facilities (tFs), and wide-area monitoring and control network (WaMcn).
the Bng and cng are the communication bridges
connecting the operation network with the other two entities. Since each of the three entities is used by different
parties and serves different purposes in the smart grid,
when interentity communications are needed, the Bng
and cng serve as firewalls that protect the operation network from external, malicious attacks. designing the Bng
and cng so that an adequate level of security can be provided without incurring too much communication delay
remains an unsolved problem, however. Furthermore, it
has not yet been decided who should maintain and operate
the gateways.
ccs are the smart grid's central control units. the
monitoring and control database (McdB), the database
storing all grid operation information, is accessed by ccs
and maintained by database managers. In the traditional
electricity grid, ccs follow a strict hierarchical design,
with each grid area controlled by a single cc that in turn
is controlled by upper-level ccs. a distributed cc design,
however, has strong advantages over the centralized one in
increasing service availability. the distributed cc design
is therefore taken as the future of control in the smart
grid. the distributed design introduces many challenging
problems, however. one such problem is the additional
communication latency brought about by distributed ccs,
especially when software techniques, such as middleware,
are used. Since ccs must sometimes process urgent messages from gSs, tFs, or SSs and respond promptly, minimizing the extra communication delay is critical. another
problem is security. Since multiple ccs will be monitoring
and controlling the same area in the distributed scenario,
if an intruder manages to hack into any one of them, he
may/june 2014

Operation Network

Business Network

Consumer Network

figure 2. A three-entity smart grid communication framework proposed in 2011 by Wen et al.

may be able to gain access to all the electrical components
in the area. For this reason, the "multiple points of attack"
issue must be carefully addressed. In addition, it is worth
noting that when a distributed cc design is adopted, the
McdB should also adopt a distributed design. If a distributed design is not used and the McdB remains centralized
while ccs are distributed, the McdB will become the system performance bottleneck and a single point of failure.
the gS component usually consists of a collection of
large power generation stations, each of which may contain many sensors and actuators connected by a local-area
network (lan) and controlled by a local control unit. the
local control unit in each gS communicates with ccs via the
WaMcn, through a gateway. this second gateway, which
complements the cng and Bng, is used to prevent insider
attacks initiated by someone who has managed to get into the
WaMcn. Since many different protocols for gS-cc communications have been developed during the past decades,
a protocol translator is needed to make the smart grid compatible with legacy technologies. designing an efficient and
effective protocol translator remains an unsolved problem,
however. designing the lan inside a gS is also challenging
because this lan must be capable of:
✔ providing a level of communication quality of service
(QoS) compatible with Ieee Standard 1646-2004
✔ functioning partially independently of local power
generation, i.e., functioning for certain time periods
even if the generators at the gS are down
✔ functioning with strong resilience against extreme
physical working conditions, such as high temperature, strong vibration, and so on.
the SS component is the collection of transmission and
electricity distribution substations. It typically has a communication structure similar to that found in the gS component.
Since distribution substations sit close to consumers and are
sometimes configured so as to have access to consumer data
via the cng, the privacy of those data must be carefully
protected. other than that, the communication requirements
inside the SS and gS components are mostly the same.
the tF component consists of the assets involved in
long-distance electricity transmission. although these
ieee power & energy magazine

39



Table of Contents for the Digital Edition of IEEE Power & Energy Magazine - May/June 2014

IEEE Power & Energy Magazine - May/June 2014 - Cover1
IEEE Power & Energy Magazine - May/June 2014 - Cover2
IEEE Power & Energy Magazine - May/June 2014 - 1
IEEE Power & Energy Magazine - May/June 2014 - 2
IEEE Power & Energy Magazine - May/June 2014 - 3
IEEE Power & Energy Magazine - May/June 2014 - 4
IEEE Power & Energy Magazine - May/June 2014 - 5
IEEE Power & Energy Magazine - May/June 2014 - 6
IEEE Power & Energy Magazine - May/June 2014 - 7
IEEE Power & Energy Magazine - May/June 2014 - 8
IEEE Power & Energy Magazine - May/June 2014 - 9
IEEE Power & Energy Magazine - May/June 2014 - 10
IEEE Power & Energy Magazine - May/June 2014 - 11
IEEE Power & Energy Magazine - May/June 2014 - 12
IEEE Power & Energy Magazine - May/June 2014 - 13
IEEE Power & Energy Magazine - May/June 2014 - 14
IEEE Power & Energy Magazine - May/June 2014 - 15
IEEE Power & Energy Magazine - May/June 2014 - 16
IEEE Power & Energy Magazine - May/June 2014 - 17
IEEE Power & Energy Magazine - May/June 2014 - 18
IEEE Power & Energy Magazine - May/June 2014 - 19
IEEE Power & Energy Magazine - May/June 2014 - 20
IEEE Power & Energy Magazine - May/June 2014 - 21
IEEE Power & Energy Magazine - May/June 2014 - 22
IEEE Power & Energy Magazine - May/June 2014 - 23
IEEE Power & Energy Magazine - May/June 2014 - 24
IEEE Power & Energy Magazine - May/June 2014 - 25
IEEE Power & Energy Magazine - May/June 2014 - 26
IEEE Power & Energy Magazine - May/June 2014 - 27
IEEE Power & Energy Magazine - May/June 2014 - 28
IEEE Power & Energy Magazine - May/June 2014 - 29
IEEE Power & Energy Magazine - May/June 2014 - 30
IEEE Power & Energy Magazine - May/June 2014 - 31
IEEE Power & Energy Magazine - May/June 2014 - 32
IEEE Power & Energy Magazine - May/June 2014 - 33
IEEE Power & Energy Magazine - May/June 2014 - 34
IEEE Power & Energy Magazine - May/June 2014 - 35
IEEE Power & Energy Magazine - May/June 2014 - 36
IEEE Power & Energy Magazine - May/June 2014 - 37
IEEE Power & Energy Magazine - May/June 2014 - 38
IEEE Power & Energy Magazine - May/June 2014 - 39
IEEE Power & Energy Magazine - May/June 2014 - 40
IEEE Power & Energy Magazine - May/June 2014 - 41
IEEE Power & Energy Magazine - May/June 2014 - 42
IEEE Power & Energy Magazine - May/June 2014 - 43
IEEE Power & Energy Magazine - May/June 2014 - 44
IEEE Power & Energy Magazine - May/June 2014 - 45
IEEE Power & Energy Magazine - May/June 2014 - 46
IEEE Power & Energy Magazine - May/June 2014 - 47
IEEE Power & Energy Magazine - May/June 2014 - 48
IEEE Power & Energy Magazine - May/June 2014 - 49
IEEE Power & Energy Magazine - May/June 2014 - 50
IEEE Power & Energy Magazine - May/June 2014 - 51
IEEE Power & Energy Magazine - May/June 2014 - 52
IEEE Power & Energy Magazine - May/June 2014 - 53
IEEE Power & Energy Magazine - May/June 2014 - 54
IEEE Power & Energy Magazine - May/June 2014 - 55
IEEE Power & Energy Magazine - May/June 2014 - 56
IEEE Power & Energy Magazine - May/June 2014 - 57
IEEE Power & Energy Magazine - May/June 2014 - 58
IEEE Power & Energy Magazine - May/June 2014 - 59
IEEE Power & Energy Magazine - May/June 2014 - 60
IEEE Power & Energy Magazine - May/June 2014 - 61
IEEE Power & Energy Magazine - May/June 2014 - 62
IEEE Power & Energy Magazine - May/June 2014 - 63
IEEE Power & Energy Magazine - May/June 2014 - 64
IEEE Power & Energy Magazine - May/June 2014 - 65
IEEE Power & Energy Magazine - May/June 2014 - 66
IEEE Power & Energy Magazine - May/June 2014 - 67
IEEE Power & Energy Magazine - May/June 2014 - 68
IEEE Power & Energy Magazine - May/June 2014 - 69
IEEE Power & Energy Magazine - May/June 2014 - 70
IEEE Power & Energy Magazine - May/June 2014 - 71
IEEE Power & Energy Magazine - May/June 2014 - 72
IEEE Power & Energy Magazine - May/June 2014 - 73
IEEE Power & Energy Magazine - May/June 2014 - 74
IEEE Power & Energy Magazine - May/June 2014 - 75
IEEE Power & Energy Magazine - May/June 2014 - 76
IEEE Power & Energy Magazine - May/June 2014 - 77
IEEE Power & Energy Magazine - May/June 2014 - 78
IEEE Power & Energy Magazine - May/June 2014 - 79
IEEE Power & Energy Magazine - May/June 2014 - 80
IEEE Power & Energy Magazine - May/June 2014 - 81
IEEE Power & Energy Magazine - May/June 2014 - 82
IEEE Power & Energy Magazine - May/June 2014 - 83
IEEE Power & Energy Magazine - May/June 2014 - 84
IEEE Power & Energy Magazine - May/June 2014 - 85
IEEE Power & Energy Magazine - May/June 2014 - 86
IEEE Power & Energy Magazine - May/June 2014 - 87
IEEE Power & Energy Magazine - May/June 2014 - 88
IEEE Power & Energy Magazine - May/June 2014 - 89
IEEE Power & Energy Magazine - May/June 2014 - 90
IEEE Power & Energy Magazine - May/June 2014 - 91
IEEE Power & Energy Magazine - May/June 2014 - 92
IEEE Power & Energy Magazine - May/June 2014 - 93
IEEE Power & Energy Magazine - May/June 2014 - 94
IEEE Power & Energy Magazine - May/June 2014 - 95
IEEE Power & Energy Magazine - May/June 2014 - 96
IEEE Power & Energy Magazine - May/June 2014 - 97
IEEE Power & Energy Magazine - May/June 2014 - 98
IEEE Power & Energy Magazine - May/June 2014 - 99
IEEE Power & Energy Magazine - May/June 2014 - 100
IEEE Power & Energy Magazine - May/June 2014 - 101
IEEE Power & Energy Magazine - May/June 2014 - 102
IEEE Power & Energy Magazine - May/June 2014 - 103
IEEE Power & Energy Magazine - May/June 2014 - 104
IEEE Power & Energy Magazine - May/June 2014 - 105
IEEE Power & Energy Magazine - May/June 2014 - 106
IEEE Power & Energy Magazine - May/June 2014 - 107
IEEE Power & Energy Magazine - May/June 2014 - 108
IEEE Power & Energy Magazine - May/June 2014 - 109
IEEE Power & Energy Magazine - May/June 2014 - 110
IEEE Power & Energy Magazine - May/June 2014 - 111
IEEE Power & Energy Magazine - May/June 2014 - 112
IEEE Power & Energy Magazine - May/June 2014 - 113
IEEE Power & Energy Magazine - May/June 2014 - 114
IEEE Power & Energy Magazine - May/June 2014 - 115
IEEE Power & Energy Magazine - May/June 2014 - 116
IEEE Power & Energy Magazine - May/June 2014 - 117
IEEE Power & Energy Magazine - May/June 2014 - 118
IEEE Power & Energy Magazine - May/June 2014 - 119
IEEE Power & Energy Magazine - May/June 2014 - 120
IEEE Power & Energy Magazine - May/June 2014 - 121
IEEE Power & Energy Magazine - May/June 2014 - 122
IEEE Power & Energy Magazine - May/June 2014 - 123
IEEE Power & Energy Magazine - May/June 2014 - 124
IEEE Power & Energy Magazine - May/June 2014 - 125
IEEE Power & Energy Magazine - May/June 2014 - 126
IEEE Power & Energy Magazine - May/June 2014 - 127
IEEE Power & Energy Magazine - May/June 2014 - 128
IEEE Power & Energy Magazine - May/June 2014 - Cover3
IEEE Power & Energy Magazine - May/June 2014 - Cover4
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091020
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070820
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050620
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030420
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010220
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111219
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091019
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070819
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050619
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030419
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010219
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111218
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091018
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070818
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050618
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030418
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010218
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111217
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091017
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070817
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050617
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030417
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010217
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111216
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091016
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070816
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050616
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030416
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010216
https://www.nxtbook.com/nxtbooks/ieee/powerenergy_010216
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111215
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091015
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070815
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050615
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030415
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010215
https://www.nxtbook.com/nxtbooks/pes/powerenergy_111214
https://www.nxtbook.com/nxtbooks/pes/powerenergy_091014
https://www.nxtbook.com/nxtbooks/pes/powerenergy_070814
https://www.nxtbook.com/nxtbooks/pes/powerenergy_050614
https://www.nxtbook.com/nxtbooks/pes/powerenergy_030414
https://www.nxtbook.com/nxtbooks/pes/powerenergy_010214
https://www.nxtbookmedia.com